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7005/7015 User Manual

1. 318VO NO 331 Q3Q T3IHS 97 NAAMA k 36 133aHS VIN JWS dSvdidu NOIL VH3dO OVA OEZ dAV 8 NOLLVHSdO OWA dV GL 3Snd WALSAS 9 SZ 1009 Lv8avo9 g NOLLVH3dO OVA 067 HOS dV NOLLVHAdO OVA SLI any 9 3Snd 1 SSIMYSHLO 2 SOL 1 NOLLVTNSNI ON ON WISH 325 N9IS3Q 400 Q3QNVH LS SMV 9 38V NMOHS 17 L GLOZ ANY 9002 O IWNVHOVIG SNISIM xai 96 90 15 fM GAGA 0091 94 108 7141133128 8L n8 1HM 9 6 600 8 HVH t t SNHOOO HVLN MY04 NVOISINV SON Svo obobobi v 9 r OIAPTTS LHM 8L OIA HOLOINNOO HALv3H hot d DL L ec SNILV3H uM oo HOLIMS Q3 LHM 81 81 ANO 8L OIA oh Ago 8 na HOLIO3NNOO 1noino XT18 038 1HM 1 TUAE M
2. 37 9 12 Serial Interface Parameters 38 9121 38 9 122 Sample Period RR SES GS OE SS Res 38 9123 sees sete anti k GUS NUS 39 9 12 4 LEGEN udo aus deer hab ices SU WAS al LS SG o 39 9 13 IEEE 488 Parameters 39 9 13 1 IEEE 488 Address 40 9 14 Calibration Parameters 40 SML Eolo ss zS yumuu se Aes sas 40 9142 Pand E uetus rw sake Al Gy Sie Q Same eR 40 10 Digital Communication Interface 43 10 1 Serial Communications 43 ar qi ok ee Due re G Aue eR GS renis ed 43 10 12 Selb ia amp ced mane ddr Het SUR uL Ga ER dS 43 10 01 25 BAUD WAS s or 44 10 1 22 5 44 10 1 2 3 44 11 12 13 14 10 24 sco RS h g Sasu Se 44 10 1 3 44 10 2 IEEE 488 Communication optional 45 IO SG Spat LICET IUE S a al Say h hos S alis at dete ag ede 45 10 2 1 1 IEEE 488 Interface Address 45 10 22 IEEE 488 45 10 3 Interface Commands 45 10 4 Power Control Functions 47 10 4 1 Heater Control
3. mesos is ss em rs yim Figure 6 Controller Operation Flowchart 30 Manual Rev 932601 Secondary Functions SET EXIT SET SET SET Configuration Menu SET IEEE 488 Interface Menu Calibration Menu Adj Device Address Adjust CTO IEEE 488 Option Installed DO NOT CHANGE THESE VALUES SEE MANUAL Adjust L SET EXIT Hart Scientific 7005 7015 9 Controller Operation This switchs the display to the set temperature function To return to displaying the temperature press the EXIT button If the cut out is still in the over temperature fault condition the display continues to flash cut out The bath temperature must drop a few degrees below the cut out set point before the cut out can be reset 93 Temperature Set point The bath temperature can be set to any value within the range and with resolu tion as given in the specifications The temperature range of the particular fluid used in the bath must be known by the operator and the bath should only be operated well below the upper temperature limit of the liquid In addition the cut out temperature should also be set below the upper limit of the fluid Setting the bath temperature involves three steps 1 select the set point memory 2 adjust the set point value and 3 adjust the vernier if desired Programmable Set points The controller stores 8 set point tempe
4. 48 10 42 Cooling s Gite San eee SOS 48 Calibration Procedure 49 11 1 Calibration Points 49 11 2 Measuring the Set point Error 49 11 3 Computing DO Dg 49 11 4 Calibration Example 50 Charging Instructions 53 T2 T Prepa alon uo ull ch ui pou Qh GA ee ie ad o3 12 2 Ghar alli a 3 ce Gos Re Se Bu m u 53 Maintenance 55 13 1 Draining the Bath 56 Troubleshooting 57 14 1 Troubleshooting 57 14 1 1 Master Reset Sequence 59 14 2 Wiring Diagram 60 IV Figures and Tables Figure 1 Table 1 Figure 2 Figure 3 Figure 4 Figure 5 Table 2 Figure 6 Figure 7 Table 3 Figure 8 Table 4 Table 4 Table 5 Table 6 Figure 9 Figure 10 Bali r en dne Qe ot to A dic 1 SPECNC ONS a m SEE perdere MO 3 FOM PANEL aks aks 15 Refrigeration Controls Side Panel 16 BACK Panel cg eur See Shoe Ke FE 18 Chart of various bath fluids and their properties 23 Table of various bath fluids and their properties 24 Controller Operation Flowchart 30 Bath temperature fluctuation at various proportional band settings
5. XT8 O38 1HM LHM o wig o p MU qaad EN L ONILV3H DE 1 J AMO LLLE0000t LYWd 8LOSO IHM OVl31 138 89d 4 l me Of erie te JONIYIHIH LLN A ma I PER AV1dSIG er 9 ym y 909 010 M 18 0HO 1HM 9805 W TIN 81 AHO YILV3H 8 MTS LHM el 9 AV 1dSIG N ir HIN 4 oOo 9 SL 1 OL LAD ZIN THADHIGLLHM zr er OVISL br pr erre op 1101 JOV4YALNI s NN ap aids OMV 97 E LH 092 010 E WNOLLdO dod SOTVNV H 81 13A 1HM TANS ho i ENER NI 2v cx h zr oo oo o THEM ME mamm 9 OO has OIAT1E LH i Nvi 9 HOLIMS WALSAS a 81 OUO NGOS br ar 8L Sj N Io D ean n lt o o oft B 2 NIGLKM Y I s o AREE eR E MMV I v GION310S HOIH GION310S SSVdA8 FENG LHM DADS 100 e SYNLWYAdNAL IYNSSIYd MOVE ERE o 0 O 81 XIIA LHM E _ OS OHLNOO Figure 10 Wiring Diagram Hart Scientific Manual Rev 932601
6. WALK x ovcesewota M Edu ee S gu BS 21 8 1 10 2 Ethylene Glycol 21 8 110 3 Methanol 21 8 1 10 4 Mineral Ol 21 8 1 10 5 Silicone saus aar Skt Setet 22 8 1 11 Fluid Characteristics Charts 22 8 1 11 1 Limitations and Disclaimer 22 8 1 11 2 Aboutthe Graph 22 da cun p 25 D 9 FOWE uuo E we eund I RE dE 25 pu BIG ia aciem Ab uhuwan er ar det BP und SG 25 8 5 GOONG 4 4 Q Qh med ined do de dome des 26 Fud Dalle bp eed Y as Sa oe Bes 26 8 7 Temperature Controller 26 9 Controller Operation 29 9 1 Bath Temperature 29 9 2 Reset Curoul US usce EE ES S E eH 29 9 3 Temperature Set point 31 9 3 1 Programmable 31 9 3 2 Set pointValue rv eee 31 9 33 SetpointVernier PE 32 94 Temperature Scale Units 32 95 Secondary Menu 33 9 6 33 9 7 ProportionalBand 34 QUE ir om dark dh dr Se Mos ee Glee es 35 9 9 Controller Configuration 36 9 10 Probe Parameters 37 S104 DO s suc REN 37 0 0 TUER 37 9 11 Operating Parameters 37 9 11 1 Cut out Reset Mode
7. With a digital interface the bath may be connected to a computer or other equipment This allows the user to set the bath temperature monitor the tem perature and access any of the other controller functions all using remote communications equipment In addition the heater power setting and cooling capacity may be controlled using the interface To enable the heater to be switched to high using the interface the HEATER switch must be set to the LOW position The cooling power switch must be set to OFF to enable re mote control Serial Communications The bath may be installed with an RS 232 serial interface that allows serial digital communications over fairly long distances With the serial interface the user may access any of the functions parameters and settings discussed in Section 9 with the exception of the BAUD rate setting The serial interface uses 8 data bits 1 stop bit and no parity 10 1 1 Wiring RS 232 Cable Wiring for The serial communications ca IBM PC and Compatibles ble attaches to the bath through the DB 9 connector at the back of the instrument Fig 10 1 2 Setup Instrument Computer DTE ure 8 shows the pin out of this BB 25 pis connector and suggested ca ne ble wiring To eliminate noise 2 RxD 2 TxD the serial cable should be 3 TxD e 3 RxD 4 NC e e 4 RTS shielded with low resistance be
8. KI Hart Scientific 7005 7015 7 Parts and Controls For this bath Set the Cooling Temp Valve to this Control Temperature pressure C F Nominal Cooling PSIG 10 14 4 7 5 23 9 2 0 32 14 5 5 41 20 7 10 50 27 9 15 59 36 1 20 68 45 5 25 77 56 2 30 86 68 4 35 95 82 1 37 98 6 86 DO NOT set the Cooling Pressure above 90 PSIG 3 The cooling temp gauge is used to indicate the temperature at which the re frigerant is evaporating The cooling temp regulating valve is used to set and then control this temperature 7 3 Back Panel The back panel has six standard features and two optional features See Fig ure 4 1 the probe connector 2 the stirrer power outlet 3 system fuses 4 the power cord 5 the drain valve 6 serial number notation 7 the RS 232 in terface conector optional and 8 the IEEE 488 interface connector optional The probe connector in the back panel is used for the temperature control ler probe The stirrer power is provided for the stirring motor The system fuses are 15 amp SB 250V The power cord is rated at 115 VAG 20 amps 230 VAG 10 amps optional A drain valve is provided for ease of removing the fluid media from the bath Always use a container of adequate size to hold the FULL LOAD of fluid Some oils are more easily drained at higher temperatures See caution note in next section The serial n
9. sa x Z w 2 RE xL Xo xx x CUN 4 34 Proportional Band Fluid Table 35 Serial Communications Cable Wiring 43 Interface Command Summary 46 Digital Communications Commands continued 47 Serial Power Control Functions 48 Temperature Range Control Functions 48 Sample Calibration Computations 51 Wiring Diagram 60 1 Introduction 1 Introduction The Hart Scientific Model 7005 and 7015 are very precise constant tempera ture baths An innovative state of the art solid state temperature controller has been incorporated which maintains the bath temperature with extreme stability The controller uses a microcontroller to execute the many operating functions User interface is provided by the 8 digit LED display and four key switches Digital remote communications is optionally available with a RS 232 or IEEE 488 interface The tanks for the 7005 and 7015 are stainless steel and holds 95 liters Figure 1 Bath Assembly 7005 7015 Manual Rev 932601 1 2 Specifications and Environmental Conditions 2 Specifications and Environmental Conditions 2 1 Specifications See Table 1 2 2 Environmental Conditions Although the instrument has been designed for optimum durability and trou ble free operation it must be handled with care The instrument should not be operated in an excessively dusty or dirty environment Maintenance
10. Configuration Read cut out setting c utout C c 9999 x xxx 110 C in Set cut out setting c utout n r eset Set cut out to n degrees c utout n c 110 Temperature Range Reset cut out now c utout r eset C r Read heater power po wer po po 9999 po 1 duty cycle Configuration Menu Probe Menu Read DO calibration parameter d0 d0 d0 999 9999 d0 25 2290 Set D0 calibration parameter to n 0 lt d0 25 2290 999 9999 to 999 9999 Read DG calibration parameter dg dg dg 999 9999 dg 186 9740 Set DG calibration parameter to n dg n dg 186 9740 999 9999 to 999 9999 Operating Parameters Menu Read cut out mode cm ode cm cm xxxx cm AUTO Set cut out mode cm ode r eset a uto RESET or AUTO Set cut out to be reset manually cm ode r eset cm r Set cut out to be reset cm ode a uto cm a automatically Serial Interface Menu Read serial sample setting sa mple sa sa 9 sa 1 Set serial sampling setting to n sa mple n sa 0 0 to 4000 seconds Set serial duplex mode du plex f ull h alf FULL or HALF Set serial duplex mode to full du plex f ull du f Set serial duplex mode to half du plex h alf du h Set serial linefeed mode Iffeed on of f ON or OFF Set serial linefeed mode to on Iffeed on If on Set serial linefeed mode to off Ifrteed of f If 0f Manual Rev 932601 Hart Scientific 10 Digital Communication Interface Digital Communications Commands continued Command Command Return
11. FOR ANY SPECIAL INDIRECT INCI DENTAL OR CONSEQUENTIAL DAMAGES OR LOSS WHETHER IN CON TRACT TORT OR OTHERWISE 4 Manual Rev 932601 Hart Scientific 7005 7015 3 Safety Guidelines 3 Safety Guidelines Operate the bath in room temperatures between 5 50 C 41 122 F Allow sufficient air circulation by leaving at least 6 inches of space between the bath and nearby objects Overhead clearance needs to allow for safe and easy insertion and removal of probes for calibration If the bath is used at higher temperatures where fluid vaporization is signif icant a fume hood should be used The bath is a precision instrument Although it has been designed for opti mum durability and trouble free operation it must be handled with care The instrument should not be operated in excessively dusty or dirty envi ronments Do not operate near flammable materials The bath generates extreme temperatures Precautions must be taken to prevent personal injury or damage to objects Probes may be extremely hot or cold when removed from the bath Cautiously handle probes to pre vent personal injury Carefully place probes on a heat cold resistant sur face or rack until they are at room temperature Use only a grounded AC mains supply of the appropriate voltage to power the bath The bath requires 15 amps at 115 VAC 10 60 Hz 8 amps at 230 VAG 10 50 Hz optional Before initial use after transport and anytime the instrument has no
12. and clean ing recommendations can be found in the Maintenance Section of this manual The instrument operates safely under the following conditions e temperature range 5 50 C 41 122 F e ambient relative humidity 15 50 e pressure 75kPa 106kPa e mains voltage within 10 of nominal e vibrations in the calibration environment should be minimized Table 1 Specifications Specifications 7005 7015 Operating Range 10 C to 110 14 F to 230 F Set point Accuracy 1 C Typical short and long term temperature stability 001 C using water at 25 C Tank Capacity 95 liters Work area 27 5 W x 12 H x 13 25 F B 70 cm x 30 5 cm x 33 7 cm Pump recirculation optional 15 L min Cooling capacity 100 200 watt Refrigeration CFC Free Heater size 500 and 1000 watt Power Requirements 115 10 60 Hz 15 A 230 10 50Hz 8 A optional Note If voltage is outside 10 VAC the com pressor may be damaged Exterior Dimensions 45 W x 17 75 H x 20 D 114 3 cm x 45 1cm x 50 8cm Shipping Weight 150 lbs 68kg 7005 7015 Manual Rev 932601 3 2 Specifications and Environmental Conditions e altitude does not effect the performance or safety of the unit 2 3 Warranty Hart Scientific Inc Hart warrants this product to be free from defects in ma terial and workmanship under normal use and service for a period as stated in our current product catalog from the
13. commands are executed but not echoed The duplex mode parameter is indicated by auunumunuunununununuanuananananananuankh auunumunununununuununaanananaanuanuank 9 12 4 Linefeed The final parameter in the serial interface menu is the linefeed mode This pa rameter enables on or disables off transmission of a linefeed character LF ASCII 10 after transmission of any carriage return The linefeed parameter is indicated by ur EEE 9 13 IEEE 488 Parameters Baths may optionally be fitted with an IEEE 488 GPIB interface In this case the user may set the interface address within the IEEE 488 parameter menu This menu does not appear on baths not fitted with the interface The menu is auununmunununununauanaanananamuanuanuqk 7005 7015 Manual Rev 932601 39 9 Controller Operation Press SET to enter the menu 9 13 1 IEEE 488 Address The IEEE 488 interface must be configured to use the same address as the external communicating device The address is indicated by Addr ESS IEEE 488 interface address Adjust the value with UP or DOWN and then use SET to set the address to the displayed value Add 15 New IEEE 488 interface address 9 14 Calibration Parameters The operator of the bath controller has access to a number of the bath calibra tion constants namely CTO H and L These values are set at the factory and must not be altered The correct values are important to the accuracy and pro
14. is pre programmed to 1200 BAUD Use UP or DOWN to change the BAUD rate value Press SET to set the BAUD rate to the new value or EXIT to abort the operation and skip to the next parameter in the menu 10 1 2 2 Sample Period The sample period is the next parameter in the menu and prompted with SAMPLE The sample period is the time period in seconds between tempera ture measurements transmitted from the serial interface If the sample rate is set to 5 the 7005 7015 transmits the current measurement over the serial in terface approximately every five seconds The automatic sampling is disabled with a sample period of 0 Press SET to choose to set the sample period Ad just the period with UP or DOWN and then use SET to set the sample rate to the displayed value 10 1 2 3 Duplex Mode The next parameter is the duplex mode indicated with auPt The duplex mode may be set to half duplex HALF or full duplex FULL With full du plex any commands received by the thermometer via the serial interface are immediately echoed or transmitted back to the device of origin With half du plex the commands are executed but not echoed The default setting is full du plex The mode may be changed using UP or DOWN and pressing SET 10 1 2 4 Linefeed The final parameter in the serial interface menu is the linefeed mode This pa rameter enables On or disables OFF transmission of a linefeed chara
15. point is ad justed to 10 or 20 C above the maximum bath operating temperature and that the cut out mode is set as desired e Ifthe cut out activates when the bath temperature is well below the cut out set point or the cut out does not reset when the bath temperature drops and it is manually reset then the cut out circuitry may be faulty or the Manual Rev 932601 57 14 Troubleshooting cut out thermocouple sensor may be faulty or disconnected Contact Hart Scientific Customer Service for assistance The display flashes CUT OUT and an incorrect process temperature The problem may be that the controller s voltmeter circuit is not functioning properly A problem could exist with the memory back up battery If the bat tery voltage is insufficient to maintain the memory data may become scrambled causing problems A nearby large static discharge may also af fect data in memory If the problem reoccurs then the battery should be replaced Contact Hart Scientific Customer Service for assistance If initializing the memory does not remedy the problem there may be a failed electronic component Con tact Hart Scientific Customer Service for assistance The displayed process temperature is in error and the controller remains in the cooling or the heating state at any set point value Possible causes may be either a faulty control probe or erroneous data in memory The probe may be disconnected burned out or shorted Check that
16. termines the serial communications transmission rate POO b Current BAUD rate The BAUD rate of the bath serial communications may be programmed to 300 600 1200 or 2400 BAUD Use UP or DOWN to change the BAUD rate value 2400 b i NewBAUD rate Press SET to set the BAUD rate to the new value or EXIT to abort the oper ation and skip to the next parameter in the menu 9 12 2 Sample Period The sample period is the next parameter in the serial interface parameter menu The sample period is the time period in seconds between temperature measurements transmitted from the serial interface If the sample rate is set to 5 the bath transmits the current measurement over the serial interface approx imately every five seconds The automatic sampling is disabled with a sample period of 0 The sample period is indicated by SAMPLE Serial sample period parameter Press SET to choose to set the sample period The current sample period value will be displayed 38 Manual Rev 932601 Hart Scientific 9 Controller Operation Adjust the value with UP or DOWN and then use SET to set the sample rate to the displayed value 9 12 3 Duplex Mode The next parameter is the duplex mode The duplex mode may be set to full duplex or half duplex With full duplex any commands received by the bath via the serial interface are immediately echoed or transmitted back to the device of origin With half duplex the
17. the certain qualities of the fluid medium in order to maintain a uniform and stable temperature envi ronment Some oils change their characteristics or become dirty after a period of use Always remove any foreign materials from the bath e Silicone oils as well as others may evaporate off their lighter components over a period of time leaving the very viscous components remaining In addition some decomposition occurs which may impair the temperature stability of the bath When this happens the fluid is generally very dark to black and viscous Vegetable oils polymerize turn plastic like after they have been used for a time at high temperatures making them very difficult to remove When the oil has become unusable it should be changed The instructions for removing the oil is as follows 13 1 Draining the Bath The drain is located on the back of the bath See Figure 4 on page 18 Locate the drain plug on the end of the drain tube This drain plug is to be fluid tight until the time of draining The following information is helpful when draining the bath Always use a container capable of holding the entire load of fluid Using an adequate size about 8 gallons or 1 cubic foot heat proof fluid container is extremely important Use safety equipment as appropriate 1 Water and low viscosity fluids Drain at room temperature Normal care must be taken for fluids that may have corrosive or damaging effects on the surrounding facility or equi
18. the controller using the front control panel is discussed in Section 9 Operation using the digital interfaces is dis cussed in Section 10 When the controller is set to a new set point the bath heats or cool to the new temperature Once the new temperature is reached the bath usually takes 10 15 minutes for the temperature to settle and stabilize There may be a small overshoot or undershoot of about 0 5 C Manual Rev 932601 27 7005 7015 9 Controller Operation 9 Controller Operation This section discusses in detail how to operate the bath temperature controller using the front control panel Using the front panel key switches and LED dis play the user may monitor the bath temperature set the temperature set point in degrees C or F monitor the heater output power adjust the controller pro portional band set the cut out set point and program the probe calibration pa rameters operating parameters serial and IEEE 488 interface configuration and controller calibration parameters Operation is summarized in Figure 6 Bath Temperature The digital LED display on the front panel allows direct viewing of the actual bath temperature This temperature value is what is normally shown on the display The units C or F of the temperature value are displayed at the right The temperature display function accessed from other function by pressing the EXIT button 9 2 Reset Cut out If the over t
19. this range The current val ues for DO and DG are 25 229 and 186 974 respectively The calibration points are chosen to be 25 00 and 75 00 C The measured bath temperatures 24 869 and 74 901 C respectively Refer to Figure 9 for applying equations to the example data and computing the new probe constants Manual Rev 932601 Hart Scientific 11 Calibration Procedure D0 25 229 DG 186 974 t 25 00 C measured t 24 869 ty 75 00 C measured t 74 901 C Compute errors err 24 869 25 00 C 0 131 C err 74 901 75 00 C 0 099 C Compute D0 0131 75 0 25 229 0099 250 25 229 750 250 DO 25 229 25392 Compute DG 0 099 0131 n 750 250 DG 11186974 187094 Figure 9 Sample Calibration Computations 7005 7015 Manual Rev 932601 51 12 Charging Instructions 12 Charging Instructions 12 1 Preparation Remove the refrigeration cover by removing the four screws that hold it on This provides access to the compressor The refrigeration system must be leak checked and then evacuated to 50 microns After the unit is evacuated it is ready to be charged 12 2 Charging After the system has been evacuated pressurize it with R 134a Next turn on the main unit power and the refrigeration power Check to make sure that the back pressure valve is completely open CCW and that there is room temper ature approx 25 C fluid
20. 25 0 4 0 00028 0 00105 1000 25 200 5 25 10 150 Silicone Oil Dow Corning 35 v 165 C fl cc 165 10 25T 0 934 25 C 0 43940 0 00032 O 0 00108 1000 25 C 200 10 3 135 0 45 100 C 25 C 50 150 C 5012 0 482 200 C Dow Corning 7 v 230 C fl cc 2307 20 25CT 0 949 25 0 370 amp 40 C 0 00034 0 00107 1000 25 C 200 20 0 393 25 C 50 150 C 5013 100 C 0 420 200 C Dow Corning 25 v 280 C fl cc 280 C 20 2502 0 96 Q 25 0 4 0 00037 0 00104 1000 25 C 200 50 25 C 50 150 C Silicone Oil Dow Corning 70 v 232 C fl cc 2327 50 7002 1 07 25 0 358 amp 40 0 00035 0 00075 100 25 C 990 300 C fl oc 10 104 C 0 386 25 C 1 150 C 5016 100 C 0 433 200 C Dow Corning 80 C v 302 C fl oc 3027 5080 1 11 25T 0 363 40 C 0 00035 0 00077 100 25 710 7 204 0 454 25 C 1 150 C 5017 100 0 505 200 C Dow Corning 66 C v 315 fl 315 50 p66 C 0 96 25 0 34 0 0003 0 00095 100 25 C 210 H 14 204 100 C 1 150 Silicone Oil Heat Transfer 145 fr 530 C NONE 34 1507 20 150 0 33 0 0014 0 00041 1 7 Q cm3 Salt 6 5 amp 300 1 9 amp 300 5001 24 500C 1 7 500 Limiting Factors b boiling point e high evaporation fl flash point fr freeze point v viscosity Flash point test open cup cc closed cup Very low water solubility ice will form as a slush from condensation below
21. 9 Controller Operation Heater Proportional Fluid Temperature Setting Band Stability Water 30 0 C Low 0 04 C 0 001 C Water 60 0 C Low 0 04 C 0 002 C Eth Gly 50 35 0 C Low 0 05 C 0 001 C Eth Gly 50 60 0 C Low 0 05 C 0 002 C Eth Gly 50 100 0 C High 0 4 C 0 007 C Oil 35 0 Low 0 1 C 0 003 C Oil 60 0 C Low 0 2 C 0 002 C Oil 100 C Low 0 2 C 0 003 C tional band settings for optimum performance with a variety of fluids at se lected temperatures The proportional band adjustment may be accessed within the secondary menu Press SET and EXIT to enter the secondary menu and show the heater power Then press SET to access the proportional band Jj d Access heater power in secondary menu auununmnunumuanunuanuanananumananamuanuanuqk To accept the new setting and access the cut out set point press SE T Pressing EXIT will exit the secondary menu ignoring any changes just made to the proportional band value se Accept the new proportional band setting 9 8 Cut out As a protection against software or hardware fault shorted heater triac or user error the bath is equipped with an adjustable heater cut out device that shuts off power to the heater if the bath temperature exceeds a set value This protects the heater and bath materials from excessive temperatures and most Manual Rev 932601 35 9 Controller Operation importantly protects the bath fluids from b
22. For example S CHR will return the current set point and s250 00 CR will set the set point to 50 00 degrees In the following list of commands characters or data within brackets and are optional for the command A slash denotes alternate characters or data Numeric data denoted by n may be entered in decimal or exponential notation Characters are shown in lower case although upper case may be used Spaces may be added within command strings and will simply be ig Manual Rev 932601 45 10 Digital Communication Interface Table 4 Interface Command Summary Command Command Returned Acceptable Command Description Format Example Returned Example Values Display Temperature Read current set point s etpoint S set 9999 99 C or F set 100 00 C Set current set point to n s etpoint n s 100 Instrument Range Read vernier v ernier V v 9 99999 v 0 00000 Set vernier to n v ernier n v 00001 Depends on Configuration Read temperature t emperature t t 9999 99 C or t 55 69 C Read temperature units u nits u x u c Set temperature units u nits c f C or F Set temperature units to Celsius u nits c U C Set temperature units to u nits f u f Fahrenheit Secondary Menu Read proportional band setting pr op band pr pr 999 9 15 9 Set proportional band to n pr op band n pr 8 83 Depends on
23. Model 7005 7015 Calibration Bath User Manual II HART SCIENTIFIC 932601 Copyright 1995 All Rights Reserved Hart Scientific 799 E Utah Valley Drive American Fork Utah 84003 9775 Telephone 801 763 1600 Fax 801 763 1010 Internet http www hartscientific com WARNING To ensure the safety of operating personnel and to avoid damage to this unit DO NOT operate this unit without a properly grounded properly polarized power cord DO NOT connect this unit to a non grounded non polarized outlet DO use a ground fault interrupt device WARNING EXTREMELY COLD TEMPERATURES PRESENT in this equipment FREEZER BURNS AND FROSTBITE may result if personnel fail to observe safety precautions WARNING HIGH TEMPERATURES PRESENT in this equipment FIRES AND SEVERE BURNS may result if personnel fail to observe safety precautions WARNING Fluids used in this bath may produce NOXIOUS OR TOXIC FUMES under certain circumstances Consult the fluid manufacturer s MSDS Material Safety Data Sheet PROPER VENTILATION AND SAFETY PRECAUTIONS MUST BE OBSERVED WARNING CALIBRATION EQUIPMENT SHOULD ONLY BE USED BY TRAINED PERSONNEL Table of Contents 1 Introduction 2 Specifications and Environmental Conditions 2 1 Specifications 2 2 Environmental Conditions 2 9 WANA k GE Ger dde S AA Unpacking s e s ko
24. acteristics to consider is the temperature range of the fluid Few fluids work well throughout the complete temperature range of the bath The temperature at which the bath is operated must always be within the safe and useful temperature range of the fluid The lower temperature range of the fluid is determined by the freeze point of the fluid or the tempera ture at which the viscosity becomes too great The upper temperature is usu ally limited by vaporization flammability or chemical breakdown of the fluid Vaporization of the fluid at higher temperatures may affect temperature stabil ity because of cool condensed fluid dripping into the bath from the lid The bath temperature should be limited by setting the safety cut out so that the bath temperature cannot exceed the safe operating temperature limit of the fluid 8 1 2 Viscosity Viscosity is a measure of the thickness of a fluid how easily it can be poured and mixed Viscosity affects the temperature stability of the bath With low vis cosity fluid mixing is better which creates a more uniform temperature throughout the bath This improves the bath response time which allows it to maintain a more constant temperature For good control the viscosity should be less than 10 centistokes 50 centistokes is about the upper limit of allowable viscosity Viscosities greater than this cause very poor control stability and may also overheat or damage the stirring motor With oils viscosity may va
25. bath applications At 10 centi Manual Rev 932601 Hart Scientific 8 General Operation L 0 100 200 300 400 500 600 Silicone Oil 710 10 CS yc LCS 10 CS FL 280 C FL 302 C Silicone Oil 200 50 Silicone Oil 200 20 10 CS FL 232 C Silicone Oil 200 10 U D me FL 163 C Silicone oil 200 05 v P FL 133 C Silicone Oil 550 10 CS FL 232 C Halocarbon 10 CS T PPW BP a x Ethylene Glycol 50 50 with H20 Bath Salt Decomposition Starts Shaded area represents usable range of fluid starting at 50 BP Boiling Point centistokes Lighter shading represents decreasing viscosity while CS Centistokes vaporization and decomposition increase EP Evaporation Point fluid loss due to evaporation too high NENNEN Black area represents liquid range with excessive viscosity FL Flash Point p FR Freeze Point PP Pour Point Range over which a fume hood is recommended Figure 5 Chart of various bath fluids and their properties stokes and below optimum stirring can occur These are rules of thumb which have been useful for most applications Fume Point The point at which a fume hood should be used This point is very subjective in nature and is impacted by individual tolerance to different fumes and smells how well the bath is covered the
26. bath to minimize temperature gradient errors Check that the calibration parameters are all correct according to the cer tification sheet If not then reprogram the constants The memory backup battery may be weak causing errors in data Check that the control probe has not been struck bent or damaged If the cause of the problem remains unknown contact Hart Scientific Customer Service for assistance Manual Rev 932601 Hart Scientific 7005 7015 14 Troubleshooting The controller shows that the output power is steady but the process temperature is unstable e Ifthe bath temperature does not achieve the expected degree of stability when measured using a thermometer try adjusting the proportional band to a narrower width as discussed in Section 9 7 The controller alternately heats for a while then cools e This oscillation is typically caused by the proportional band being too nar row Increase the width of the proportional band until the temperature sta bilizes as discussed in Section 9 7 The controller erratically heats then cools control is unstable e If both the bath temperature and output power not vary periodically but in a very erratic manner the problem may be excess noise in the system Noise due to the control sensor should be less than 0 001 C However if the probe has been damaged or has developed an intermittent short er ratic behavior may exist Check for a damaged probe or poor connection between th
27. c ter LF ASCII 10 after transmission of any carriage return The default setting is with linefeed on The mode may be changed using UP or DOWN and pressing SET 10 1 3 Serial Operation Once the cable has been attached and the interface set up properly the con troller immediately begins transmitting temperature readings at the pro grammed rate The set point and other commands may be sent to the bath via the serial interface to set the bath and view or program the various parame ters The interface commands are discussed in Section 10 3 All commands are ASCII character strings terminated with a carriage return character CR ASCII 13 Manual Rev 932601 Hart Scientific 7005 7015 10 Digital Communication Interface IEEE 488 Communication optional The IEEE 488 interface is available as an option Baths supplied with this op tion may be connected to a GPIB type communication bus which allows many instruments to be connected and controlled simultaneously To eliminate noise the GPIB cable should be shielded Setup To use the IEEE 488 interface first connect an IEEE 488 standard cable to the back of the bath Next set the device address This parameter is programmed within the IEEE 488 interface menu To enter the IEEE 488 parameter programming menu first press EXIT while pressing SET and release to enter the secondary menu Press SET repeat edly until the display reaches Pr 0bE This is the menu s
28. d an ignition source is applied the vapor will ignite This does not necessarily mean that fire will be sustained at the flash point The flash point may be either of the open cup or closed cup Manual Rev 932601 Hart Scientific 7005 7015 8 General Operation type Either condition may occur in a bath situation The closed cup tempera ture is always the lower of the two The closed cup represents the contained vapors inside the tank and the open cup represents the vapors escaping the tank Oxygen and an ignition source will be less available inside the tank Environmentally hazardous fluids require special disposal according to appli cable federal or local laws after use 8 1 9 Cost Cost of bath fluids may vary greatly from cents per gallon for water to hun dreds of dollars per gallon for synthetic oils Cost may be an important consid eration when choosing a fluid 8 1 10 Commonly Used Fluids Below is a description of some of the more commonly used fluids and their characteristics Water Water is often used because of its very low cost availability and excellent tem perature control characteristics Water has very low viscosity and good thermal conductivity and heat capacity which makes it among the best fluids for control stability at low temperatures Temperature stability is much poorer at higher temperatures because water condenses on the lid cools and drips into the bath Water is safe and relatively inert The elect
29. date of shipment This warranty extends only to the original purchaser and shall not apply to any product which in Hart s sole opinion has been subject to misuse alteration abuse or abnormal conditions of operation or handling Software is warranted to operate in accordance with its programmed instruc tions on appropriate Hart products It is not warranted to be error free Hart s obligation under this warranty is limited to repair or replacement of a product which is returned to Hart within the warranty period and is determined upon examination by Hart to be defective If Hart determines that the defect or malfunction has been caused by misuse alteration abuse or abnormal condi tions or operation or handling Hart will repair the product and bill the pur chaser for the reasonable cost of repair To exercise this warranty the purchaser must forward the product after calling or writing Hart for authorization Hart assumes NO risk for in transit damage For service or assistance please contact the manufacturer Hart Scientific Inc 799 East Utah Valley Drive American Fork UT 84003 9775 Phone 801 763 1600 Fax 801 763 1010 E mail support hartscientific com THE FOREGOING WARRANTY IS PURCHASER S SOLE AND EXCLUSIVE REMEDY AND IS IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IM PLIED INCLUDING BUT NOT LIMITED TO ANY IMPLIED WARRANTY OR MERCHANTABILITY OR FITNESS FOR ANY PARTICULAR PURPOSE OR USE HART SHALL NOT BE LIABLE
30. displays an incorrect bath temper ature but the controller otherwise appears to operate normally The prob lem may be either insufficient heating or no heating at all or too much cooling Insufficient heating may be caused by the heater power setting being too low especially at higher operating temperatures Switching to the higher heater power switch setting if available may solve the problem Try reducing cooling capacity by increasing the cooling temperature switching the cooling power switch to LOW or switching off the cooling altogether e Oneor more burned out heaters or blown heater fuses may also cause this problem If the heaters seem to be burned out contact Hart Scientific Cus tomer Service for assistance The controller display flashes CUT OUT and the heater does not oper ate e Thedisplay will flash CUT OUT alternately with the process temperature If the process temperature displayed seems grossly in error perform the Master Reset Sequence Section 14 1 1 Normally the cut out discon nects power to the heater when the bath temperature exceeds the cut out set point causing the temperature to drop back down to a safe value If the cut out mode is set to AUTO the heater switches back on when the tem perature drops If the mode is set to RESET the heater only comes on again when the temperature Is reduced and the cut out is manually reset by the operator See Section 9 8 Check that the cut out set
31. e weed cR RS OX A Beare 4 2 SOLD La dot woke Bee an he ae Sod Re ede C a 4 3 JPOWOE p Se uiri S Ibo pesa dex ee dede CR N 4 4 Setting the Temperature 5 Installation 2 2 2 2 2 2 2 2 T 08058 s s eee 11 5 1 BathEnvironment 52 Dryout Period 5 3 Bath Preparation and Filling 54 SJPIODS RUM m w y Ro RS RR Oo POWs vss pr Ns es SME tee ra 6 188 uoc S Beds L Seed a a 13 61 General a amos a Beds SUS 6 2 Comparison Calibration 6 3 Calibration of Multiple Probes Parts Controls 15 7 1 Front Control Panel 7 2 Side Panel 7 3 Back Panel saga baa ad BSD Be uem we 8 General Operation 19 8 1 Bath Fluid 8 1 1 Temperature MISCOSIIV us Oo SD Op d S bee a i 813 Speciic ss ads ack a Yup OS salt 8 1 4 Thermal Conductivity 8 1 5 Thermal Expansion 8 1 6 Electrical Resistivity SLT FUdbemne ENTER NS a a ka ee das Bn TT SAU Sse ea i e ee Sue Ss Bo W RERE N ONG Eug husk WC but S aoe aw tara Bs der PS ee d e d 8 1 10 Commonly Used Fluids 04
32. e most useful op erating range of the bath The farther apart the calibration temperatures the larger will be the calibrated temperature range but the calibration error will also be greater over the range If for instance 20 C and 80 C are chosen as the cal libration temperatures the bath may achieve an accuracy of say 0 2 C over the range 20 to 80 C Choosing 30 C and 70 C may allow the bath to have a better accuracy of maybe 0 05 C over the range 30 to 70 C but outside that range the accuracy may be only 0 5 C 11 2 Measuring the Set point Error The first step in the calibration procedure is to measure the temperature errors including sign at the two calibration temperatures First set the bath to the lower set point which we will call t Wait for the bath to reach the set point and allow 15 minutes to stabilize at that temperature Check the bath stability with the thermometer When both the bath and the thermometer have stabilized measure the bath temperature with the thermometer and compute the temper ature error err which is the actual bath temperature minus the set point tem perature If for example the bath is set for a lower set point of t 20 C and the bath reaches a measured temperature of 19 7 C then the error is 0 3 C Next set the bath for the upper set point t and after stabilizing measure the bath temperature and compute the error For our example we will suppose the bath was set for 80 C and the the
33. e probe and bath e Intermittent shorts in the heater or controller electronic circuitry may also be a possible cause Contact Hart Scientific Customer Service for assis tance The bath does not achieve low temperatures e his problem can be caused by too much heating or not enough cooling Check that the control indicator glows green showing that the controller is attempting to cool The heaters may be disabled as a test by temporarily removing the heater fuses e Maximize cooling by switching the cooling on setting the cooling power to high if applicable and setting the cooling temperature to 10 15 below the bath set point see the chart on the bath e Insufficient cooling may be caused by lack of refrigerant because of a leak in the system Refer to Section 12 Charging Instruction Master Reset Sequence Hold the SET and EXIT keys down at the same time while powering up the unit The display shows the model number and the firmware version Each of the controller parameters and calibration constants must be re programmed The values can be found on the Report of Calibration that was shipped with the instrument Manual Rev 932601 59 14 Troubleshooting iagram D iring 14 2 W
34. e than 10 days the bath will need to be energized for a dry out period of 1 2 hours before it can be assumed to meet all of the safety requirements of the IEC 1010 1 5 3 Preparation and Filling The Model 7005 and 7015 Baths are not provided with a fluid Various fluids are available from Hart Scientific and other sources Depending on the desired temperature range any of the following fluids as well as others may be used in the bath e Water Manual Rev 932601 11 5 Installation 12 e Ethylene Glycol Water e Methanol e Mineral oil e Silicone oil Fluids are discussed in detail in Section 8 1 Remove any access hole cover from the bath and check the tank for foreign matter dirt remnant packing material etc Use clean unpolluted fluid Care fully fill the bath through the large square access hole to a level that will allow for stirring and thermal expansion The fluid should never exceed a height of 1 2 below the top of the tank Carefully monitor the bath fluid level as the bath temperature rises to prevent overflow or splashing Remove excess fluid if nec essary and with caution if the fluid is hot Be careful to prevent bath fluid from spilling on the stirring motor while filling Note Underfilling may reduce bath performance and may possibly dam age the bath heater 5 4 Probe Inspect the bath controller probe This probe should not be bent or damaged in any way Reasonable caution should be used in hand
35. ed Acceptable Command Description Format Example Returned Example Values Calibration Menu Read low set point limit value tl ow tl tl 999 tl 80 Set low set point limit to n tl 80 999 9 to 999 9 Read high set point limit value th igh th th 999 th 205 Set high set point limit to n th igh n th 205 999 9 to 999 9 Miscellaneous not on menus Read firmware version number ver sion ver ver 9999 9 99 ver 2100 3 56 Read structure of all commands h elp h list of commands Read Heater f1 f1 f1 9 Set Heater f1 1 0 0 or 1 Set heater to low f1 n f1 0 Set heater to high f1 n f1 1 Read Refrigeration f2 f2 12 9 12 0 Set Refrigeration f2 1 0 0 or 1 Set Refrigeration to on f2 n f2 1 Set Refrigeration to off f2 n f2 0 Read Expansion Valve 1 f3 f3 3 9 13 1 Set Expansion Valve 1 f3 1 0 0 or 1 Set Expansion Valve 1 to on f3 n f3 1 Set Expansion Valve 1 to off f3 n f3 0 Read Cooling Power f4 f4 14 9 14 1 Set Back Pressure f4 1 0 0 or 1 Set back pressure on f4 n f4 1 Set back pressure off f4 n f4 0 Legend Note Optional Command data Returns either information n Numeric data supplied by user 9 Numeric data returned to user x Character data returned to user When DUPLEX is set to FULL and a command is sent to READ the command is returned followed by a carriage return and linefeed Then the value is returned as indicated in the RETURNED c
36. eing heated beyond the safe operat ing temperature preventing hazardous vaporization breakdown or ignition of the liquid The cut out temperature is programmable by the operator from the front panel of the controller It must always be set below the upper tempera ture limit of the fluid and no more than 10 degrees above the upper tempera ture limit of the bath If the cut out is activated because of excessive bath temperature power to the heater shuts off and the bath cools The bath cools until it reaches a few de grees below the cut out set point temperature At this point the action of the cut out is determined by the setting of the cut out mode parameter The cut out has two selectable modes automatic reset or manual reset If the mode is set to automatic the cut out automatically resets itself when the bath tempera ture falls below the reset temperature allowing the bath to heat up again If the mode is set to manual the heater remains disabled until the user manually re sets the cut out The cut out set point may be accessed within the secondary menu Press SET and EXIT to enter the secondary menu and show the heater power Then press SET twice to access the cut out set point scr Access heater power secondary menu To accept the new cut out set point press SET se Accept cut out set point The next function is the configuration menu Press EXIT to resume displaying the bath temp
37. election Press UP repeatedly until the IEEE 488 interface menu is indicated with EEE Press SET to enter the IEEE 488 parameter menu The IEEE 488 menu contains the IEEE 488 address parameter IEEE 488 Interface Address The IEEE 488 address is prompted with Addr E55 Press SET to program the address The default address is 22 Change the device address of the bath If necessary to match the address used by the communication equipment by pressing UP or DOWN and then SET IEEE 488 Operation Commands may now be sent via the IEEE 488 interface to read or set the temperature or access other controller functions All commands are ASCII character strings and are terminated with a carriage return CR ASCII 13 In terface commands are listed below Interface Commands The various commands for accessing the bath controller functions via the digi tal interfaces are listed in this section see Table 4 These commands are used with both the RS 232 serial interface and the IEEE 488 GPIB interface In either case the commands are terminated with a carriage return character The interface makes no distinction between upper and lower case letters hence either may be used Commands may be abbreviated to the minimum number of letters which determines a unique command A command may be used to either set a parameter or display a parameter depending on whether or not a value is sent with the command following a character
38. emperature cut out has been triggered then the temperature dis cut out Indicates cut out condition The message continues to flash until the temperature is reduced and the cut out is reset The cut out has two modes automatic reset and manual reset The mode determines how the cut out is reset which allows the bath to heat up again When in automatic mode the cut out resets itself as soon as the temperature is lowered below the cut out set point With manual reset mode the cut out must be reset by the operator after the temperature falls below the set point When the cut out is active and the cut out mode is set to manual reset then the display will flash cut out until the user resets the cut out To access the reset cut out function press the SET button sx Access cut out reset function auunununununnunuununanauanananmananuk Press SET once more to reset the cut out ser Reset cut out Manual Rev 932601 29 9 Controller Operation Display Temperature SET eset Cutout Cutout Active SET EXIT Adjust Setpoint EXIT Adjust Vernier EXIT Set Scale C F Interface Menu Parameters Menu Rate SET Adjust BAUD Rate SET EXIT Adj Cutout Reset Mode Sample Period Adj Sample Period Duplex Mode T Adj Duplex Mode SET EXIT SET Adjust Linefeed RS 232 Option Installed m
39. erature 9 9 Controller Configuration The controller has a number of configuration and operating options and cali bration parameters which are programmable via the front panel These are ac cessed from the secondary menu after the cut out set point function by pressing SET There are 5 sets of configuration parameters probe param eters operating parameters serial interface parameters IEEE 488 interface parameters and controller calibration parameters The menus are selected us ing the UP and DOWN keys and then pressing SET Manual Rev 932601 Hart Scientific 9 Controller Operation 9 10 Probe Parameters The probe parameter menu is indicated by Press SET to enter the menu The probe parameters menu contains the pa rameters DO and Dg which characterize the resistance temperature relation ship of the thermistor control probe These parameters may be adjusted to improve the accuracy of the bath This procedure is explained in detail in Sec tion 11 The probe parameters are accessed by pressing SET after the name of the parameter is displayed The value of the parameter may be changed using the UP and DOWN buttons After the desired value is reached press SET to set the parameter to the new value Pressing EXIT will cause the parameter to be skipped ignoring any changes that may have been made 9 10 1 DO This probe parameter refers to the resistance of the contr
40. esults can generally be achieved by starting at the highest temperature and progressing down to the lowest temperature Probes can be held in place in the bath by using probe clamps or drilling holes in the access cover Other fixtures to hold the probes can be designed The object is to keep the reference probe and the probe s to be calibrated as closely grouped as possible in the working area of the bath Bath stability is maximized when the bath working area is kept covered In preparing to use the bath for calibration start by e Placing the reference probe in the bath working area e Placing the probe to be calibrated the UUT in the bath working area as close as feasibly possible to the reference probe 6 3 Calibration of Multiple Probes Fully loading the bath with probes increases the time required for the tempera ture to stabilize after inserting the probes Using the reference probe as the guide be sure that the temperature has stabilized before starting the calibra tion Manual Rev 932601 Hart Scientific 7 Parts and Controls 7 Parts and Controls 7 1 Front Control Panel The following controls and indicators are present on the controller front panel see Figure 2 below 1 the digital LED display 2 the control buttons 3 the bath on off power switch 4 the control indicator light 5 the heater power switch and 6 the cooling power switch 1 The digital display is an important part of the temperature c
41. fic to the fluid selected Generally baths are set to one temperature and used to calibrate probes only at that single temperature This means that the type of bath fluid does not have to change Additionally the bath can be left energized reducing the stress on the system The bath generates extreme temperatures Precautions must be taken to pre vent personal injury or damage to objects Probes may be extremely hot or cold when removed from the bath Cautiously handle probes to prevent per sonal injury Carefully place probes on a heat cold resistant surface or rack un til they are at room temperature It is advisable to wipe the probe with a clean soft cloth or paper towel before inserting it into another bath This prevents the mixing of fluids from one bath to another If the probe has been calibrated in liquid salt carefully wash the probe in warm water and dry completely before transferring it to another fluid Always be sure that the probe is completely dry before inserting it into a hot fluid Some of the high temperature fluids react vi olently to water or other liquid mediums Be aware that cleaning the probe can be dangerous if the probe has not cooled to room temperature Additionally high temperature fluids may ignite the paper towels if the probe has not been cooled For optimum accuracy and stability allow the bath adequate stabilization time after reaching the set point temperature 6 2 Comparison Calibration Comparison ca
42. freezing 24 Boiling Point At the boiling point of the fluid the temperature stability is diffi cult to maintain Fuming is excessive Excessive amounts of heater power may be required because of the heat of vaporization Manual Rev 932601 Hart Scientific 7005 7015 8 General Operation Decomposition All high temperature fluids may be reach a temperature point at which decomposition of some form will begin While it always begins slowly at some lower temperature the rate can increase to the point of danger or im practicality at a higher temperature 8 2 Stirring Stirring of the bath fluid is very important for stable temperature control The fluid must be mixed well for good temperature uniformity and fast controller re sponse The stirrer is precisely adjusted for optimum performance 83 Power Power to the bath is provided by an AC mains supply of 115 VAC 10 60 Hz 15 A 230 VAC 10 50 Hz 8 A optional Power to the bath passes through a filter to prevent switching spikes from being transmitted to other equipment To turn on the bath switch the control panel power switch to the ON position The stir motor will turn on the LED display will begin to show the bath temper ature and the heater will turn on or off until the bath temperature reaches the programmed set point When powered on the control panel display briefly shows a four digit number This number indicates the number of times power has been ap
43. frigeration switch must be off The refrigeration power function is controlled with the F2 command Setting the F2 value to 0 turns the refrigeration off and setting it to 1 turns it on F2 alone returns 0 or 1 showing the state of the refrigeration power control The F3 command controls the high and low cooling temperature range or expansion valves As discussed in Section 7 2 this valve adjusts the cooling temperature which sets the cooling capacity Setting F3 to 1 opens the valve on or high and 0 closes the valve off or low A command with no value re turns the current value With the valve closed the cooling temperature is set with the cooling temperature knob labeled LOW This should be adjusted for approximately 9 14 psi if the bath is to be used as low as 10 C The knob la beled HIGH controls the cooling temperature when the expansion valve is open or on This should be adjusted for approximately 45 50 psi These values are typical but may be adjusted as required for specific applications The low range must be set to a lower pressure temperature than the high range valve The F4 command controls the back pressure valve When the valve is open the cooling capacity is significantly reduced This valve should normally be left off closed throughout the operating range of the bath Table 5 summarizes the control functions for heating and cooling Table 6 shows the recommended control settings fo
44. hh auunununuununununuanuananananamunuanunkh Press SET to accept the new selection and resume displaying the bath tem perature SET Set the new units and resume temperature display 9 5 Secondary Menu Functions which are used less often are accessed within the secondary menu The secondary menu is accessed by pressing SET and EXIT simulta neously and then releasing The first function in the secondary menu is the heater power display 9 6 Heater Power The temperature controller controls the temperature of the bath by pulsing the heater on and off The total power being applied to the heater is determined by the duty cycle or the ratio of heater on time to the pulse cycle time This value may be estimated by watching the red green control indicator light or read di rectly from the digital display By knowing the amount of heating to the bath the user can tell if the bath is heating up to the set point cooling down or control ling at a constant temperature Monitoring the percent heater power will let the user know how stable the bath temperature is With good control stability the percent heating power should not fluctuate more than 1 within one minute The heater power display is accessed in the secondary menu Press SET and EXIT simultaneously and release The heater power will be displayed as a percentage of full power SET Access heater power secondary menu Se To exit out of
45. ically have significant thermal expan sion 8 1 6 Electrical Resistivity Electrical resistivity describes how well the fluid insulates against the flow of electric current In some applications such as measuring the resistance of bare temperature sensors it may be important that little or no electrical leak age occur through the fluid In this case consider a fluid with very high resistiv ity 8 1 7 Fluid Lifetime Many fluids degrade over time because of evaporization water absorption gelling or chemical breakdown Often the degradation becomes significant near the upper temperature limit of the fluid 8 1 8 Safety When choosing a fluid always consider the safety issues associated Obvi ously where there are extreme temperatures there can be danger to person nel and equipment Fluids may also be hazardous for other reasons Some fluids may be considered toxic Contact with eyes skin or inhalation of vapors may cause injury A proper fume hood must be used if hazardous or bother some vapors are produced WARNING Fluids at high temperatures May pose danger from BURNS FIRE and TOXIC fumes Use appropriate caution and safety equipment Fluids may be flammable and require special fire safety equipment and proce dures An important characteristic of the fluid to consider is the flash point The flash point is the temperature at which there is sufficient vapor given off so that when there is sufficient oxygen present an
46. ies are available Press UP DOWN to change the set point value Increment display C 30 00 New set point value Press SET to accept the new value and display the vernier value The bath begins heating or cooling to the new set point se Store new set point access vernier 0 00000 Current vernier value Press EXIT and the bath temperature is displayed again Return to the temperature display 13 Bath temperature display The bath heats or cools until it reaches the new set point temperature Set the heater switch to position HIGH to allow the bath to more quickly reach a higher temperature The HIGH setting may be necessary to reach higher temperatures and control at high temperatures Manual Rev 932601 Hart Scientific 7005 7015 4 Quick Start When setting the set point temperature be careful not to exceed the tempera ture limit of the bath fluid The over temperature cut out should be correctly set to prevent this from happening See Section 9 8 If operating the bath below 45 C set the COOLING power switch to ON The cooling temperature may require adjustment to provide the proper amount of cooling See Section 8 5 To obtain optimum control stability adjust the proportional band as discussed in Section 9 7 Manual Rev 932601 9 7005 7015 5 Installation Installation CAUTION READ SECTION 6 ENTITLED BATH USE before placing the bath in service Incorrect handl
47. imit can compromise safety or serviceability Sources of information sometimes vary for particular properties Your company s safety policies as well as per sonal judgment regarding flash points toxicity etc must also be considered You are responsible for reading the Material Safety Data Sheets and making a judgment here Cost may require some compromises as well Hart Scientific cannot be liable for the suitability of application or for any personal injury dam age to equipment product or facilities in using these fluids The charts include information on a variety of fluids which are often used as heat transfer fluid in baths Because of the temperature range some fluids may not be useful with your bath 8 1 11 2 About the Graph 22 The fluid graph visually illustrates some of the important qualities of the fluids shown Temperature Range The temperature scale is shown in degrees Celsius A sense of the fluid s general range of application is indicated Qualities including pour point freeze point important viscosity points flash point boiling point and others may be shown Freezing Point The freezing point of a fluid is an obvious limitation to stirring As the freezing point is approached high viscosity may also limit good stirring Pour Point This represents a handling limit for the fluid Viscosity Points shown are at 50 and 10 centistokes Greater than 50 centi stokes stirring is very poor and unsatisfactory for
48. in the bath Using the cooling power valve located on the side of the unit adjust the pressure reading to 10 psi Charge with 15 oz of R 134a If a gauge or scale is not available add R 134a slowly through the low pressure side until the sight glass located at the back of the unit is full This sight glass should begin to show gas between 15 and 20 psi but should be full below that pressure 7005 7015 Manual Rev 932601 7005 7015 13 Maintenance 13 Maintenance The calibration instrument has been designed with the utmost care Ease of operation and simplicity of maintenance have been a central theme in the product development Therefore with proper care the instrument should require very little maintenance Avoid operating the instrument in dirty or dusty environments The bath should be cleaned regularly to prevent a buildup of oil or dust Use a paint safe cleaning agent on all painted surfaces Solvents such as Trichloroethylene or Acetone may dull or dissolve the paint The stainless steel surfaces may be cleaned with solvents as necessary to remove oils The stirring motor should be clean to allow proper cooling Normally only the outside surfaces require any attention If the inside of the motor has be come heavily loaded with oily dust blow it out with compressed air Follow normal safety procedures when using pressurized gasses Periodically check the fluid level in the bath to ensure that the level has not dropped A dro
49. ing can damage the bath and void the warranty This bath is not designed to be portable Therefore moving the bath once it has been installed should be kept to a minimum Never move a bath that is full of fluid This action could be extremely dangerous and could result in personal injury to the person moving the bath If the bath is going to be placed in an area where it will need to be moved fre quently a special cart can be designed to accommodate the bath making the bath much more portable Hart sells carts designed for these baths However even with a cart the bath should not be moved full of fluid The fluid can splash causing injury or if the bath and cart tip the fluid could cause damage to the surrounding area and personal injury to personnel If the bath must be moved be sure to drain the fluid to prevent any injury The side of the bath with the compressor is heavier than the tank side To safely move the bath two people are required Bath Environment The Model 7005 and 7015 Baths are precision instrumenst which should be located in an appropriate environment The location should be free of drafts extreme temperatures and temperature changes dirt etc The surface where the bath is placed must be level If used at higher temperatures where fluid vaporization is significant a fume hood should be used Dry out Period Before initial use after transport and any time the instrument has not been energized for mor
50. libration involves testing a probe unit under test UUT against a reference probe After inserting the probes to be calibrated into the bath al low sufficient time for the probes to settle and the temperature of the bath to stabilize One of the significant dividends of using a bath rather than a dry well to cali brate multiple probes is that the probes do not need to be identical in construc tion The fluid in the bath allows different types of probes to be calibrated at the same time However stem effect from different types of probes is not totally eliminated Even though all baths have horizontal and vertical gradients these gradients are minimized inside the bath work area Nevertheless probes should be inserted to the same depth in the bath liquid Be sure that all probes Manual Rev 932601 13 6 Bath Use 14 are inserted deep enough to prevent stem effect From research at Hart Scien tific we suggest a general rule of thumb for immersion depth to reduce the stem effect to a minimum 15 x the diameter of the UUT the sensor length Do not submerge the probe handles If the probe handles get too warm dur ing calibration at high temperatures a heat shield could be used just below the probe handle This heat shield could be as simple as aluminum foil slid over the probe before inserting it in the bath or as complicated as a specially de signed reflective metal apparatus When calibrating over a wide temperature range better r
51. ling this probe as it con tains a precision thermistor sensor If damaged the probe can be replaced Contact Hart Scientific Customer Service for assistance Insert the probe into the 1 4 inch probe hole at the top left side of the bath lid The tip of the probe must be well immersed in the fluid The probe connector is plugged into the rear of the bath into the socket labelled PROBE 5 5 Power With the bath power switch off plug the bath into an AC mains outlet of the ap propriate voltage frequency and current capacity Normally this will be 115 VAC 10 60 Hz 15 A or 230 VAC 10 50 Hz 8 A optional Be sure the stirring motor power cord is plugged into the STIRRER socket at the back of the bath Manual Rev 932601 Hart Scientific 7005 7015 6 Bath Use 6 Bath Use READ BEFORE PLACING THE BATH IN SERVICE The information in this section is for general information only It is not designed to be the basis for calibration laboratory procedures Each laboratory will need to write their own specific procedures General Be sure to select the correct fluid for the temperature range of the calibration Bath fluids should be selected to operate safely with adequate thermal proper ties to meet the application requirements Also be aware that some fluids ex pand and could overflow the bath if not watched Refer to General Operation section 8 for information specific to fluid selection and to the MSDS sheet speci
52. luid could cause damage to the sur rounding area and personal injury to personnel If the bath must be moved be sure to drain the fluid to prevent any injury The side of the bath with the compressor is heavier than the tank side To safely move the bath two people are required Manual Rev 932601 5 4 Quick Start 4 Quick Start CAUTION READ SECTION 6 ENTITLED BATH USE before placing the bath in service Incorrect handling can damage the bath and void the warranty This section gives a brief summary of the steps required to set up and operate the 7005 7015 bath This should be used as a general overview and reference and not as a substitute for the remainder of the manual Please read Section 5 through 7 carefully before operating the bath 41 Unpacking Unpack the bath carefully and inspect it for any damage that may have oc curred during shipment If there is shipping damage notify the carrier immedi ately Verify that all components are present e 7005 7015 Bath e Controller Probe e Access Hole Cover e Manual If you are missing any item please call Hart Scientific Customer Service at 801 763 1600 4 2 Set Up Set up of the bath requires careful unpacking and placement of the bath filling the bath with fluid installing the probe and connecting power Consult Section 5 for detailed instructions for proper installation of the bath Be sure to place the bath in a safe clean and level location Fill the bath tank
53. ol probe at 0 C Normally this is set for 225 2290 ohms 9 10 2 DG This probe parameter refers to the average sensitivity of the probe between 0 and 100 C Normally this is set for 186 9740 9 11 Operating Parameters Press SET to enter the menu The operating parameters menu contains the cut out reset mode setting 9 11 1 Cut out Reset Mode The cut out reset mode determines whether the cut out resets automatically when the bath temperature drops to a safe value or must be manually reset by the operator auununununuanunuununuanannananmananuqk Press SET to access the parameter setting Normally the cut out is set for automatic mode auunununnununnunununununaanuananananuankhh 7005 7015 Manual Rev 932601 37 9 Controller Operation To change to manual reset mode press UP and then SET CEo r Sk Cut out set for manual reset 9 12 Serial Interface Parameters The 7005 7015 bath may optionally be fitted with an RS 232 interface The se rial RS 232 interface parameters menu is indicated by SE IA Serial RS 232 interface parameters menu The serial interface parameters menu contains parameters which determine the operation of the serial interface These controls only apply to baths fitted with the serial interface The parameters in the menu are BAUD rate sam ple period duplex mode and linefeed 9 12 1 BAUD Rate The BAUD rate is the first parameter in the menu The BAUD rate setting de
54. olumn nored Backspace BS ASCII 8 may be used to erase the previous character A terminating CR is implied with all commands 10 4 Power Control Functions 7005 7015 The digital interface is capable of controlling the heating and cooling functions so that the bath can be remotely operated at any temperature within the range of the bath To allow the interface to control the heating and the cooling the front panel controls are disabled by 1 switching the heater switch to LOW and 2 switching the refrigeration switch to OFF Otherwise the interface would not be able to switch these functions off The 7005 7015 bath has four control functions with the digital interface These are heater power high low cooling on off expansion valve on off and back pressure valve on off Manual Rev 932601 47 10 Digital Communication Interface 10 4 1 Heater Control To control the heater with the digital interface the front panel heater switch must be set to LOW 500 W The heater function is controlled with the F1 command Setting the F1 parameter to 0 sets the heater to LOW 500 W and setting it to 1 sets the heater to HIGH 1000 W Sending F1 with no value causes the controller to return a value showing what the heater setting is When the heater setting is changed a pop is heard as the heater relay opens or closes 10 4 2 Cooling Control To control the refrigeration power with the digital interface the front panel re
55. ontroller be cause it not only displays set and actual temperatures but also displays vari ous bath functions settings and constants The display shows temperatures in values according to the selected scale units C or F 2 The control buttons SET DOWN UP and EXIT are used to set the bath temperature set point access and set other operating parameters and access and set bath calibration parameters A brief description of the functions of the buttons follows SET Used to display the next parameter in a menu and to set parameters to the displayed value DOWN Used to decrement the displayed value of settable parameters UP Used to increment the displayed value EXIT Used to exit from a menu When EXIT is pressed any changes made to the displayed value are ignored 3 The on off switch controls power to the entire bath assembly lt powers the stirring motor and the bath controller heater circuit 4 The control indicator is a two color light emitting diode This indicator lets the user visually see the ratio of heating to cooling When the indicator is red the heater is ON When the indicator is green the heater is OFF and the bath is cooling 5 The heater power switch is used to select the appropriate heater power lev els for heating and controlling the bath at various temperatures 4 HEATIN G COOLING PO WER HEATER MODE DOWN UP EXIT SET High Predsion Bath MM SCIENTIFIC Fig
56. per and safe operation of the bath Access to these parameters is available to the user only so that in the event that the controller s memory fails the user may restore these values to the factory settings The user should have a list of these constants and their settings with the manual DO NOT change the values of the bath calibration constants from the factory set values The correct setting of these pa rameters is important to the safety and proper operation of the bath Press SET five times to enter the menu 9 14 1 CTO Parameter CTO sets the calibration of the over temperature cut out This is not adjustable by software but is adjusted with an internal potentiometer For the 7005 7015 baths this parameter should read between 120 9 14 2 HandL These parameters set the upper and lower set point limits of the bath DO NOT change the values of these parameters from the factory set values To do e Manual Rev 932601 Hart Scientific 9 Controller Operation so may present danger of the bath exceeding its temperature range causing damage or fire 7005 7015 Manual Rev 932601 41 7005 7015 10 Digital Communication Interface 10 Digital Communication Interface If supplied with the option the 7005 7015 bath is capable of communicating with and being controlled by other equipment through the digital interface Two types of digital interface are available the RS 232 serial interface and the IEEE 488 GPIB interface
57. pin the fluid level affects the stability of the bath Changes in fluid level are dependent upon several factors specific to the environment in which the equipment is used A schedule cannot be outlined to meet each environmental setting Therefore the first year the bath should be checked weekly with notes kept as to changes in bath fluid After the first year the user can set up a maintenance schedule based on the data spe cific to the application Heat transfer medium lifetime is dependent upon the type of medium and the environment The fluid should be checked at least every month for the first year and regularly thereafter This fluid check provides a baseline for knowledge of bath operation with clean usable fluid Once some fluids have become compromised the break down can occur rapidly Particular attention should be paid to the viscosity of the fluid A significant change in the viscosity can indicate that the fluid is contaminated being used outside of its temperature limits contains ice particles or is close to a chemical breakdown Once data has been gathered a specific maintenance sched ule can be outline for the instrument Refer to the General Operation sec tion Section 8 for more information aboutthe different types of fluids used in calibration baths If a hazardous material is spilt on or inside the equipment the user is re sponsible for taking the appropriate decontamination steps as outlined by the national safety co
58. plied to the bath Also briefly displayed is data which indicates the controller hardware con figuration This data is used in some circumstances for diagnostic purposes 8 4 Heater The power to the bath heater is precisely controlled by the temperature con troller to maintain a constant bath temperature Power is controlled by periodi cally switching the heater on for a certain amount of time using a solid state relay The front panel red green control indicator shows the state of the heater The control indicator glows red when the heater is on and glows green when the heater is off The indicator will pulse constantly when the bath is maintaining a stable temperature The heater has two power level settings The HIGH heater power setting is used to quickly heat up the bath fluid to the desired operating temperature The HIGH heater power setting may also be required for control at high tem peratures The LOW setting is used for control at lower temperatures and for scanning at slower rates When controlling at the HIGH heater power setting instead of LOW the proportional band may need to be increased typically by a factor of four to compensate for the increase in power gain Otherwise the temperature may oscillate Manual Rev 932601 25 8 General Operation 8 5 Cooling The back pressure control valve limits the cooling capacity of the unit It will normally be open all the way full CCW for tempera
59. pment 2 High viscosity oils The fluid should be sufficiently low in viscosity to drain efficiently Some oils such as 710 silicone oil may need to be heated to 80 C to be fluid enough to drain well The viscosity affects how rapidly it drains as well as how well it flows off of the walls Heat proof containers and appropriate safety equipment such as face shields gloves and body covering are recommended WARNING Extreme danger of BURNS and FIRE Use safety equipment use proper equipment and have fire safety equipment standing by Manual Rev 932601 Hart Scientific 7005 7015 14 Troubleshooting 14 Troubleshooting Troubleshooting In the event the bath appears to function abnormally this section may help to find and solve the problem Several possible problem conditions are described along with likely causes and solutions If a problem arises please read this section carefully and attempt to understand and solve the problem If the bath seems faulty or the problem cannot otherwise be solved then contact Hart Scientific Customer Service for assistance When contacting Customer Ser vice please have the following infomation Model Number Serial Number AC Voltage Company Name A wiring diagram is also included Opening the unit without contacting Hart Scientific Customer Service may void the warranty The heater indicator LED stays red but the temperature does not in crease e hedisplay does not show cut out nor
60. r each operating temperature range The ranges may need to be adjusted depending on the bath application Table 5 Serial Power Control Functions Table 6 Temperature Range Control Functions Function Comman 0 1 Range Heater Refr Exp Back d 10 to 15 C low on off off Heater ON high 15 to 40 C low on on off ou en 40to110 high off off off Expansion valve F3 off low high Back pressure F4 off on 48 Manual Rev 932601 Hart Scientific 7005 7015 11 Calibration Procedure Calibration Procedure In some instances the user may want to calibrate the bath to improve the tem perature set point accuracy Calibration is done by adjusting the controller probe calibration constants DO and DG so that the temperature of the bath as measured with a standard thermometer agrees more closely with the bath set point The thermometer used must be able to measure the bath fluid tem perature with higher accuracy than the desired accuracy of the bath By using a good thermometer and carefully following the procedure the bath can be cal ibrated to an accuracy of better than 0 1 C over a range of 50 degrees Calibration Points In calibrating the bath DO and DG are adjusted to minimize the set point error at each of two different bath temperatures Any two reasonably separated bath temperatures may be used for the calibration however best results are ob tained when using bath temperatures which are just within th
61. ratures in memory The set points can be quickly recalled to conveniently set the bath to a previously programmed temperature set point To set the bath temperature one must first select the set point memory This function is accessed from the temperature display function by pressing SET The number of the set point memory currently being used is shown at the left on the display followed by the current set point value Press SET to accept the new selection and access the set point value se Accept selected set point memory 9 3 2 Set point Value The set point value may be adjusted after selecting the set point memory and pressing SET The set point value is displayed with the units C or F at the urt EEE Manual Rev 932601 31 9 Controller Operation If the set point value need not be changed then press EXIT to resume dis playing the bath temperature Press UP or DOWN to adjust the set point value C 42 58 New set point value When the desired set point value is reached press SET to accept the new value and access the set point vernier If EXIT is pressed instead then any changes made to the set point will be ignored se Accept new set point value 9 3 3 Set point Vernier The set point value can only be set with a resolution of 0 002 C The user may want to adjust the set point slightly to achieve a precise bath temperature The set point vernier allows one to adjust the
62. rical conductivity of water may prevent its use in some applications Water has a limited temperature range from a few degrees above 0 C to a few degrees below 100 C At higher tem peratures evaporation becomes significant Water used in the bath should be distilled or softened to prevent mineral deposits Consider using an algicide chemical in the water to prevent contamination 8 1 10 2 Ethylene Glycol The temperature range of water may be extended by using a solution of 1 part water and 1 part ethylene glycol antifreeze The characteristics of the ethyl ene glycol water solution are similar to water Use caution with ethylene glycol since the fluid is very toxic Ethylene glycol must be disposed of properly 8 1 10 3 Methanol Methanol or methyl alchohol is often used at low temperatures below 0 C Methanol is relatively inexpensive has good control characteristics and has a low freeze point Methanol is very toxic so care must be taken when using and disposing of this fluid 8 1 10 4 Mineral Oil Mineral oil or paraffin oil is often used at moderate temperatures above the range of water Mineral oil is relatively inexpensive At lower temperatures min eral oil is quite viscous and control may be poor At higher temperatures vapor emission becomes significant The vapors may be dangerous and a fume hood should be used As with most oils mineral oil will expand as temperature in creases so be careful not to fill the bath too full
63. rmometer measured 80 1 C giving an er ror of 0 1 C 11 3 Computing DO and DG Before computing the new values for DO and DG the current values must be known The values may be found by either accessing the probe calibration menu from the controller panel or by inquiring through the digital interface The user should keep a record of these values in case they may need to be re stored in the future The new values DO and DG are computed by entering Manual Rev 932601 49 11 Calibration Procedure the old values for DO and DG the calibration temperature set points t and t and the temperature errors errL and errH into the following equations _ ert t DO err t DO t DO DO ty ioc If for example DO and DG were previously set for 25 229 and 186 9740 re spectively and the data for t t and were as given above then the new values DO and would be computed as 25 831 and 188 220 respec tively Program the new values DO and DG into the controller The new con stants will be used the next time the bath temperature is set Check the calibration by setting the temperature to t and t and measuring the errors again If desired the calibration procedure may be repeated again to further im prove the accuracy 11 4 Calibration Example The bath is to be used between 25 and 75 C and it is desired to calibrate the bath as accurately as possible for operation within
64. ry greatly with temperature When using fluids with higher viscosities the controller proportional band may need to be increased to compensate for the reduced response time Otherwise the temperature may begin to oscillate 8 1 3 Specific Heat Specific heat is the measure of the heat storage ability of the fluid Specific heat though to a lesser degree also affects the control stability and the heat ing and cooling rates Generally a lower specific heat causes slightly better control stability and quicker heating and cooling With fluids with higher spe cific heat the controller may require a decreased proportional band to compen sate for the decrease in sensitivity of the bath temperature to heat input Manual Rev 932601 19 8 General Operation 8 1 4 Thermal Conductivity Thermal conductivity measures how easily heat flows through the fluid Ther mal conductivity of the fluid affects the control stability temperature uniformity and probe temperature settling time Fluids with higher conductivity distribute heat more quickly and evenly improving bath performance 8 1 5 Thermal Expansion Thermal expansion describes how the volume of the fluid changes with tem perature Thermal expansion of the fluid used must be considered since the in crease in fluid volume as the bath temperature changes may cause overflow Excessive thermal expansion may also be undesirable in applications where constant liquid level is important Oils typ
65. surface area of the fluid in the bath the size and ventilation of the facility where the bath is located and others We assume the bath is well covered at this point This is also subject to company policy Flash Point The point at which ignition may occur See flash point discussion in Section 8 1 8 The point shown may be either the open or closed cup flash point 7005 7015 Manual Rev 932601 23 8 General Operation Table 2 Table of various bath fluids and their properties Fluid Lower Upper Specific Thermal Thermal Temperatur Temperatur Flash Viscosity Specific Heat Conductivity Expansion Resistivity Model No eLimit e Limit Point centistokes Gravity cal g C gt 1012 cm Halocarbon 0 8 90 v 70 C e NONE 5 7 50 C 1 71 Q 40 0 2 0 0004 0 001 1 9019 0 8 40 0 5 amp 70 Methanol 96 C fr 60 C b 54 139 35 0 810 0 0 6 0 0005 0 0014 0 66 0 0 792 20 20 C 25 C 0 45 20 Water OC fr 95 C b NONE 1 25 1 00 1 00 0 0014 0 0002 0 4 75 25 C Ethylene 35 fr 110 b NONE 70 1 05 0 8 0 C 0 001 Glycol 50 2 50 5020 0 7 100 C Mineral Oil 40 C v 190 C f 19070 15 75 0 87 25 048 25 0 00025 0 0007 5 25 C 5 125 _ 084 75 0 53 Q 75 C 25 C 50 0 81 125 0 57 125 C Dow 40 v 133 fl 133 5 25 0 92
66. t been energized for more than 10 days the bath needs to be energized for a dry out period of 1 2 hours before it can be assumed to meet all of the safety requirements of the IEC 1010 1 The bath is equipped with operator accessible fuses If a fuse blows it may be due to a power surge or failure of a component Replace the fuse once If the fuse blows a second time it is likely caused by failure of a component part If this occurs contact Hart Scientific Customer Service Always re place the fuse with one of the same rating voltage and type Never re place the fuse with one of a higher current rating If a mains supply power fluctuation occurs immediately turn off the bath Power bumps from brown outs and black outs can damage the compres sor Wait until the power has stabilized before re energizing the bath This bath is not designed to be portable Therefore moving the bath once it has been installed should be kept to a minimum Never move a bath that is full of fluid This action could be extremely dangerous and could result in personal injury to the person moving the bath If the bath is going to be placed in an area where it will need to be moved frequently a special cart can be designed to accommodate the bath making the bath much more portable Hart sells carts designed for these baths However even with a cart the bath should not be moved full of fluid The fluid can splash causing injury or if the bath and cart tip the f
67. temperature below or above the set point by a small amount with very high resolution Each of the 8 stored set points has an associated vernier setting The vernier is accessed from the set point by pressing SET The vernier setting is displayed as a 6 digit num ber with five digits after the decimal point This is a temperature offset in de grees of the selected units C or F 0 00000 Current vernier value in To adjust the vernier press UP or DOWN Unlike most functions the vernier setting has immediate effect as the vernier is adjusted SET need not be pressed This allows one to continually adjust the bath temperature with the vernier as it is displayed 0 00090 i New vernier setting Next press EXIT to return to the temperature display or SET to access the temperature scale units selection se Access scale units 9 4 Temperature Scale Units The temperature scale units of the controller may be set by the user to de grees Celsius C or Fahrenheit F These units are used in displaying the bath temperature set point vernier proportional band and cut out set point The temperature scale units selection is accessed after the vernier adjustment function by pressing SET From the temperature display function access the units selection by pressing SET 4 times Manual Rev 932601 Hart Scientific 7005 7015 9 Controller Operation auununmnunununununanunaanananamnuanuan
68. temperature is monitored with a thermistor resistance sensor in the control probe The signal is electronically compared with the programmable reference signal amplified and then fed to a pulse width modulator circuit which controls the amount of power applied to the bath heater The bath is operable within the temperature range given in the specifications For protection against solid state relay failure or other circuit failure the microcontroller automatically turns off the heater with a second mechanical re lay anytime the bath temperature is more than a certain amount above the set point temperature As a second protection device the controller is also equipped with a separate thermocouple temperature monitoring circuit which shuts off the heater if the temperature exceeds the cut out set point The controller allows the operator to set the bath temperature with high resolu tion set the cut out adjust the proportional band monitor the heater output power and program the controller configuration and calibration parameters The controller may be operated in temperature units of degrees Celsius or Fahrenheit The controller is operated and programmed from the front control panel using the four key switches and digital LED display The controller may also be optionally equipped with a serial RS 232 or IEEE 488 GPIB digital in Manual Rev 932601 Hart Scientific 7005 7015 8 General Operation terface for remote operation Operation of
69. that it overflows when heated Manual Rev 932601 21 8 General Operation The viscosity and thermal characteristics of mineral oil is poorer than water so temperature stability will not be as good Mineral oil has very low electrical conductivity Use caution with mineral oil since it is flammable and may also cause serious injury if inhaled or ingested 8 1 10 5 Silicone Oils 8 1 11 8 1 11 1 Silicone oils are available which offer a much wider operating temperature range than mineral oil Like most oils silicone oils have temperature control characteristics which are somewhat poorer than water The viscosity changes significantly with temperature and thermal expansion also occurs These oils have very high electrical resistivity Silicon oils are fairly safe These oils are relatively expensive Fluid Characteristics Charts Table 2 and Figure 5 have been created to provide help in selecting a heat ex change fluid media for your constant temperature bath The charts provide both a visual and numerical representation of most of the physical qualities im portant in making a selection The list is not all inclusive many usable fluids may not have been shown in this listing Limitations and Disclaimer Every effort has gone into making these charts accurate however the data here does not imply any guarantee of fitness of use for a particular application Working near the limits of a property such as the flash point or viscosity l
70. the probe is connected properly The probe may be checked with an ohmmeter to see if itis open or shorted The probe is a platinum 4 wire Din 43760 type therefore the resistance should read 0 2 to 2 0 ohms between pins 1 and 2 on the probe connector and 0 2 to 2 0 ohms between pins 3 and 4 The resistance should read from 100 to 300 ohms between pins 1 and 4 depending on the temperature If the probe is defective contact Hart Scientific Customer Service for assistance If the problem is not the probe erroneous data in memory may be the cause Perform the Master Reset Sequence Section 14 1 1 If the prob lem remains the cause may be a defective electronic component Contact Hart Scientific Customer Service for assistance The controller controls or attempts to control at an inaccurate tempera ture The controller operates normally except when controlling at a specified set point At this set point the temperature does not agree with that mea sured by the user s reference thermometer to within the specified accu racy This problem may be caused by an actual difference in temperature between the points where the control probe and thermometer probe mea sure temperature by erroneous bath calibration parameters or by a dam aged control probe Check that the bath has an adequate amount of fluid in the tank and that the stirrer is operating properly Check that the thermometer probe and control probe are both fully in serted into the
71. the secondary menu press EXIT To continue on to the propor tional band setting function press SET Manual Rev 932601 33 9 Controller Operation 9 7 Proportional Band In a proportional controller such as this the heater output power is proportional to the bath temperature over a limited range of temperatures around the set point This range of temperature is called the proportional band At the bot tom of the proportional band the heater output is 100 At the top of the pro portional band the heater output is O Thus as the bath temperature rises the heater power is reduced which consequently tends to lower the temperature back down In this way the temperature is maintained at a fairly constant tem perature The temperature stability of the bath depends on the width of the proportional band See Figure 7 If the band is too wide the bath temperature will deviate excessively from the set point due to varying external conditions This is be cause the power output changes very little with temperature and the controller cannot respond very well to changing conditions or noise in the system If the proportional band is too narrow the bath temperature may swing back and forth because the controller overreacts to temperature variations For best con trol stability the proportional band must be set for the optimum width The optimum proportional band width depends on several factors among which are fluid volume fluid characteris
72. tics viscosity specific heat thermal conductivity heater power setting operating temperature and stirring Thus the proportional band width may require adjustment for best bath stability when any of these conditions change Of these the most significant factors af fecting the optimum proportional band width are heater power setting and fluid viscosity The proportional band should be wider when the higher power set ting is used so that the change in output power per change in temperature re mains the same The proportional band should also be wider when the fluid viscosity is higher because of the increased response time The proportional band width is easily adjusted from the bath front panel The width may be set to discrete values in degrees C or F depending on the se lected units The optimum proportional band width setting may be determined by monitoring the stability with a high resolution thermometer or with the con troller percent output power display Narrow the proportional band width to the point at which the bath temperature begins to oscillate and then increase the band width from this point to 3 or 4 times wider Table 3 lists typical propor ww Proportional Band too Narrow Proportional Band too Wide Optimum Proportional Band L lia gg EE c Figure 7 Bath temperature fluctuation at various proportional band settings Manual Rev 932601 Hart Scientific 7005 7015 Table 3 Proportional Band Fluid Table
73. ture slewing and opera tion If during operation the front panel meter indicates excessive cooling this valve is closed partially turn CW until the percentage of heating to cooling is brought into line It is necessary to wait a few minutes after each adjustment until the system settles Set the COOLING TEMPERATURE to 5 10 C below the SET TEMPERATURE for near ambient and below operation For temperature above 16 C set the COOLING TEMPERATURE at 7 C The cooling temperature should NOT be set above 7 C or 90 psig About 45 C the refrigeration will not be required as there is sufficient cooling to the room Wait a few minutes after each adjust ment until the system establishes itself Readjust if required after settling for a while For maximum cooling for slewing to lower temperatures the BACK PRES SURE valve should be fully open and the COOLING TEMPERATURE set to 0 C Readjust higher or lower as required after set temperature is reached 8 6 Fluid Drain The drain at the back of the bath see Figure 4 and Figure on pages 18 may be used to remove fluid from the bath During operation of the bath the drain must be closed 8 7 Temperature Controller The bath temperature is controlled by Hart Scientific s unique hybrid digital an alog temperature controller The controller offers the tight control stability of an analog temperature controller as well as the flexibility and programmability of a digital controller The bath
74. tween the connector DB 9 6 NC e 6 7 RTS e e 7 GND and the shield Ro I 9 NC e e 20 Before operation the serial in Computer DTE t t terface of the bath must first be 9 Pin DB 9 Pin set up by programming the INC 1 NC BAUD rate and other configu 2 RxD 2 RxD 3 TxD e e 3 TxD ration parameters These pa ANG 4 NC rameters are programmed 5 GND 5 GND ith 6 NC e e e 6 NC within the serial interface EIS RIS menu 8 CTS e 8 CTS 9 NC e e 9 NC To enter the serial parameter programming mode first press Figure 8 Serial Communications Cable Wiring Manual Rev 932601 44 10 Digital Communication Interface EXIT while pressing SET and release to enter the secondary menu Press SET repeatedly until the display reads Pr obE This is the menu selection Press UP repeatedly until the serial interface menu is indicated with 5E r IRL Finally press SET to enter the serial parameter menu In the serial in terface parameters menu are the BAUD rate the sample rate the duplex mode and the linefeed parameter BAUD rate The BAUD rate is the first parameter in the menu The display will prompt with the BAUD rate parameter by showing BRUd Press SET to choose to set the BAUD rate The current BAUD rate value will then be displayed The BAUD rate of the 7005 7015 serial communications may be programmed to 300 600 1200 or 2400 BAUD The BAUD rate
75. umber is located on the right side of the back panel When call ing Customer Service use the serial number and model number If the bath is supplied with a serial RS 232 interface the interface cable at taches to the back of the bath at the connector labeled RS 232 Manual Rev 932601 17 7 Parts and Controls 8 Ifthe bath is supplied with a GPIB IEEE 488 interface the interface cable attaches to the back of the bath at the connector labeled IEEE 488 Extreme caution must be maintained to prevent harm to the user or the surrounding environment Do not exceed a 120 C fluid temperature for draining The valve could be damaged if 120 C is exceeded Insulate the container from the floor or other objects that may be damaged by high temperatures as required RS 232 Optional 7 lt Qhan IEEE 488 Optional I a I Figure 4 Back Panel 18 Manual Rev 932601 Hart Scientific 7005 7015 8 General Operation 8 General Operation Bath Fluid Many fluids will work with 7005 7015 bath Choosing a fluid requires consider ation of many important characteristics of the fluid Among these are tempera ture range viscosity specific heat thermal conductivity thermal expansion electrical resistivity fluid lifetime safety and cost Temperature Range One of the most important char
76. uncil with respect to the material MSDS sheets ap plicable to all fluids used in the baths should be kept in close proximity to the instrument If the mains supply cord becomes damaged replace it with a cord with the appropriate gauge wire for the current of the bath If there are any ques tions call Hart Scientific Customer Service for more information Before using any cleaning or decontamination method except those rec ommended by Hart users should check with Hart Scientific Customer Service to be sure that the proposed method will not damage the equip ment Manual Rev 932601 55 13 Maintenance e fthe instrument is used in a manner not in accordance with the equipment design the operation of the bath may be impaired or safety hazards may arise e he over temperature cut out should be checked every 6 months to see thatitis working properly In order to check the user selected cut out follow the controller directions Section 9 8 for setting the cut out Both the man ual and the auto reset option of the cut out should be checked Set the bath temperature higher than the cut out Check to see if the display flashes cut out and the temperature is decreasing Note When checking the over temperature cut out be sure that the temperature limits of the bath fluid are not exceeded Exceeding the temperature limits of the bath fluid could cause harm to the operator lab and instrument e he constant temperature bath depends upon
77. ure 2 Front Panel 7005 7015 Manual Rev 932601 15 7 Parts and Controls 6 The cooling power switch controls power to the cooling compressor and cooling fan 7 2 Side Panel The side panel has three features see Figure 3 1 the back pressure valve 2 the cooling temperature regulating valve and 3 the cooling temp gauge With the interface option an extra cooling valve HIGH is provided 1 The back pressure valve adjustment is used to control the amount of cool ing supplied to the system This valve reduces the cooling capacity by re stricting the flow of refrigerant to the bath allowing the adjustment of the heating to cooling percentage Under normal operation the valve should be fully open counter clockwise 2 Thecooling temperature regulating valve is used to adjust the temperature at which the refrigerant evaporates which determines cooling efficiency The ideal temperature for operation is about 5 10 degrees Celsius below the desired bath temperature Refer to the label below the gauge for ap proximate psi and evaporative temperature settings The following table is reproduced from the label f Standard Back Pressure Cooling Temperature X d e KI Back Pressure Low Cooling Temperature High uU e With Interface M optional G e Figure 3 Refrigeration Controls Side Panel 16 Manual Rev 932601
78. with an appropriate liquid For operation at moderate bath temperatures clean distilled water works well Carefully pour the fluid into the bath tank through the large rectangular access hole above the tank avoiding spilling any fluid The fluid must not exceed a height of 1 2 inch below the bath lid The control probe must be inserted through the lid into the bath and plugged into the socket at the back of the bath 4 3 Power Plug the bath power cord into a mains outlet of the proper voltage frequency and current capability Typically this will be 115 VAC 10 60 Hz 15 A 230 VAC 10 50 Hz 8 A optional Set the HEATER switch on the front panel 7005 7015 Manual Rev 932601 7 4 Quick Start to position LOW and turn the bath on using the front panel POWER switch The bath will turn on and begin to heat or cool to reach the previously pro grammed temperature set point The front panel LED display will indicate the actual bath temperature 4 4 Setting the Temperature In the following discussion a solid box around the word SET UP EXIT or DOWN indicates the panel button while the dotted box indicates the display reading Explanation of the button or display reading are to the right of each button or display value To view or set the bath temperature set point proceed as follows The front When SET is pressed the display shows the set point memory that is cur rently being used and its value Eight set point memor

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