Adam Equipment PGW PRECISION BALANCES
Contents
1. Adam Equipment Company 2007 26 Ensure that the weight pan is clear then press Setup Enter After measuring the no load weight the display will prompt to load the external calibration mass Load the required mass and press Setup Enter lf temperature calibration at the other temperature has already been performed successfully after measuring the weight of the calibration mass the instrument will display the current temperature correction in parts per million per degree Celsius as PPM CORR xxx until any key is pressed to return to the TEMP CAL menu option If temperature calibration at the other temperature has not been performed the instrument will return immediately to the TEMP CAL menu option Pressing the Mode key at any time escapes back to the TEMP CAL menu option Pressing the Esc key at any time returns to weighing lf any measurement errors are encountered an appropriate error message will flash on the display until any key is pressed when the instrument will return to the TEMP CAL menu opiion If any errors are encountered or the Mode or Esc keys are pressed during temperature calibration the procedure will be aborted with no new data stored and any previous temperature correction data will be retained B LINEAR CAL Display will ask to load the required weights in turn Place the weights onto the weighing pan in turn and press the Setup Enter key Please note that the weights are not selecta2. REPEATABILITY ADJUSTMENT lf the errors are still not acceptable refer to section 7 0 for adjustment Adam Equipment Company 2007 14 5 3 ECCENTRIC LOADING TESTING rj 4 5 1 3 2 7 A Check the balance readings in the positions marked Place the mass shown in the table below at the center of the pan After stabilization record the value Move the mass to the next point half way between the center and the edge of the pan Record the results for each point e The readings on the edges should match with the reading at the center point within the tolerances shown TABLE 6 ECCENTRIC LOADING ERRORS Balance model Mass___ Acceptable error PGW 1502 PGW 2502 1000g 0 02g PGW 3502 1000g 0 02g PGW 4502 1000g 0 02g If the differences in the weighing values at the 5 locations are bigger than 5 divisions you need to adjust the balance for Eccentric loading ECCENTRIC LOADING ADJUSTMENT These adjustments will result in moving the mounting points for the flexures so that the mechanical assembly is set right to produce the same weighing results regardless of the position of the mass on the weighing platform The adjustment is done using the hex head bolts on the mechanics The amount of adjustment and the direction by which the screws are turned will depend on the amount of error observed as the mass is moved around the platform Adam Equipment Company 2007 15 Hexagonal Screws Place
3. The user is asking the balance for something it cannot do or is confused by the modes and functions of a balance It is also possible the user has set a parameter that has affected the balance operation Resetting the parameter to a normal value will restore operation Mechanical Problems The balances consist of complicated and fragile mechanical devices They can be damaged by placing a weight on it which is too high for the balance or by dropping the balance or occasionally shipping it without taking care The most fragile parts are the flexures Dust dirt spills and other foreign objects in the balance can also cause problems Electronic Problems These are the rarest of the problems affecting balances If an electronic problem is Suspected make sure the mechanical problems that can cause similar symptoms have been eliminated before attempting electronic repairs With the exception of cables most electronic repairs are solved by PCB replacement The Electronics modules within the balance are not serviceable In case of any electronics component failure contact your Supplier The following table provides a guideline on the common problems Note that many problems may have multiple solutions and there may be problems found that are not listed in the table For more Information contact your supplier TABLE 2 TROUBLE SHOOTING BALANCE DOES NOT FUNCTION Suggestions The balance is dead Power supply failure Check adapter is working W
4. 45009 It is necessary to know the values of the masses used to an accuracy that is better than the balance weighing results NOTE The accumulation of errors when using multiple masses can contribute to a larger apparent error Refer to Table 3 If you are using 200g amp 50g masses to make 250g there may be an accumulated error of 0 0010g 0 0003g 0 0013g The error at each value is determined by computing Error Displayed mass actual mass TABLE 8 LINEARITY ERRORS Balance model Acceptable error PGW 253 0 003g PGW 753 0 003g LINEARITY ADJUSTMENT If the values are still not acceptable refer to section 7 0 for Linearity adjustment Adam Equipment Company 2007 18 6 0 MECHANICAL REPAIRS The mechanical repairs which are normally required will be Replace broken or damaged flexures Cleaning or replacing of magnet and drive coil Each of these is explained in the following section The part numbers for ordering the components needed during the repair are listed in the Annexure at the end see Table 13 Rear Screw 1 Rear Screw 2 Stainless Steel pan Rubber pan support lt t 3 mm Allen Hex Keys Top saddle Adam Equipment Company 2007 2 bottom screws Step 1 To open the PGW Balance first remove the two screws on the rear panel using the 2 5mm Allen Hex Keys Step 2 Remove the stainless steel pan and the 4 rubber pan supports Step 3 Hold
5. EHZ ADAM Adam Equipment PGW PRECISION BALANCES SERVICE MANUAL ADAM EQUIPMENT CO LTD P N 8236 Rev A7 April 2007 Adam Equipment Company 2007 Adam Equipment Company 2007 CONTENTS EO INTRODUCTION EEN 3 20 DESCRIPTION OF CONSTRUCTION 20505 geetarun esu genee gek rider pisnge Sio E aaa 4 2h ERNGIREESEOFERATION pill 4 2 MODELDIFFERENCES dai 6 2 3 INTERNAL CALIBRATION BALANCES AA 7 2 4 EQUIPMENT AND TOOLS REQUIRED io 8 SSES Oe RE EN RE 9 40 TROUBLESHOOTING GUIDES EE 10 5 0 FUNCTIONAL TESTS AND ADJUSTMENTS nen nan 13 5 1 REPEATABILITY TESTING AT INTERNAL CALIBRATION MASS 13 5 2 REPEATABILITY TESTING AT FULL CAPACITY aaa aaaeacawaaeacace 14 5 3 ECCENTRIC LOADING TESTING 15 SE GN ECH CHE E TESTING EE 17 6 0 MEGAANIGAL REPAIRS snc 19 ET EE 29 8 0 INTERNAL CALIBRATION MASS ADIUGITMENT annan 28 90 CGABLESAND CONNECTIONS o 30 10 0 BALANCE MENU DIAGRAM Sacca 31 KI BAGANGE Eeer eege 34 i EA EE ODE EE 34 11 2 MAIN MECHANICS ASSEMBLY GE 35 Adam Equipment Company 2007 1 Adam Equipment Company 2007 1 0 INTRODUCTION The PGW series of precision balances are very precise measuring devices used in the laboratory conditions To achieve precise measurements you should make sure the balances are used in Suitable environments and the conditions are as described in the Operators Manuals There are no user serviceable parts in the balance All service and internal calibrations should be do
6. US Mommes MM N Parts counting Percent weighing Check weighing Animal weighing Net total weighing Density Enable Baud Rate Parity OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON OFF ON 4800 9600 19200 38400 NONE EVEN ODD Only when stable OFF ON Continuous OFF ON Periodic s ni OFF ON Standard form Format mi Single Custom form 1 Custom form 2 Language English French German Spanish Time 0 Hour Minute Second Date format e Date Year Weekday European dd mm yy USA mm dd yy Set time period seconds Set form 1 format Set form 2 format Set hour 0 23 Set minute 0 59 Set second 0 59 Set year 0 99 Set month 0 12 Day of month Set day of month Set day of week Instrument identifier Set instrument identifier 0 9999999 Buzzer OFF ON Backlight OFF ON AUTO Power down ela OFF ON Set power down time minutes Filter Set filter depth seconds Stability Set stability level divisions Auto zero TE OFF ON Set auto zero range divisions CAL SETUP Setup calibration parameters Enable calibration NO YES Calibration report
7. OFF ON Auto cal with time gie OFF ON Set auto cal time hours Auto cal with temp E OFF ON __ Set auto cal temp change C PASSCODES Set passcodes ADO Operator Enter old code Set new code Supervisor Enter old code Set new code DEALER ADC COUNTS Display ADC counts 77 Weight ADC counts UNIT key toggles Temp ADC counts T displayed DATA COMMS Output configuration data Displays ACTIVE Press PRINT button Upload configuration data Download configuration data Data output at 9600 N 8 1 CALIBRATE Temperature amp linearity cal Temp cal lt a Low temperature Enter low cal temp C e Z High temperature Enter high cal temp C Perform external calibration Linearity calibration Load prompted cal masses Internal cal enable T NO if fitted YES or Adjust internal mass Factory setting 100mg Not available on OEM units Adam Equipment Company 2007 33 11 0 BALANCE DIAGRAMS 11 1 EXPLODED VIEW Stainless Steel pan Pan Support Assembly Power Supply PCB M Pan Support Spacers x 4 Mechanics Main PCB Magnet Assembly Balance Casing 34 Adam Equipment Company 2007 11 2 MAIN MECHANICS ASSEMBLY Magnet Cover Upper Horizontal Beam al As n ad WK St A gt FS Main gt Chasis Off Centre Loading Coil Beam
8. key Select enabled modes Parts counting Select reference quantity Load reference quantity Percent weighing T Sample weight Load 100 weight Entered weight Enter 100 weight Check weighing Low checkweight limit OFF High checkweight limit Tt ON Buzzer OFF Ei OUT Auto start load weight Delay time Solid Water Other 2 Net total weighing Density Liquid eer Enter volume of reference solid Setup key Supervisor passcode enabled T No Yes Enter supervisor passcode Supervisor Enter dealer passcode TE Dealer Adam Equipment Company 2007 31 Animal weighing T Run Manual start press ENTER Setup Manual auto start TF _ L_ Test time Set delay time seconds Set lower weight limit Set upper weight limit Manual start Auto start Set test time seconds Set autostart threshold Enter water temperature C Enter ethanol temperature C Enter density of liquid g cc Display supervisor menu Display dealer menu SUPERVISOR UNITS MODES SERIAL SETUP Enable disable units Enable disable modes Setup serial parameters Setup machine parameters foe a la E Milligrams mg Kilograms ka Carats c t Pennyweights dwt Grains GN Troy ounces ozt Ounces oz Pounds Ib Drams dr Taels H Taels T Taels S Tolas T Ticals ti Newtons Custom K t1H tIT
9. resistors are selected to optimise the voltage to the A D converter The flexures See Table 1 for details Pan support springs or leaf springs The external and internal calibration models the internal calibration models are available with motorised internal calibration as series denoted with T The same models are available with external calibration facility as series denoted with e All other changes are set by parameters stored in memory and set at the factory by the manufacturer and can not be modified outside the factory TABLE 1 LIST OF FLEXURES Flexures Flexures for 0 01g models for 0 001g models Pivots x 2 NOTE To order for spare flexures refer to Table 14 at the end of this manual Adam Equipment Company 2007 6 2 3 INTERNAL CALIBRATION BALANCES The mechanism for controlling the internal calibration mass consists of Internal calibration masses 1 Retaining Plates 2 Lever for mechanism 3 to move the masses Electrical motor 4 with cam 5 operated from the microprocessor Motor Bracket 6 Position Sensor 7 Weight hanger 8 Plastic weight lifter 9 Exploded view of Internal Calibration Mechanism for PGW with 0 001 readability NOTE For PGW with 0 01 readability components number 1 amp 2 vary from the above the rest of the components are same Internal Calibration process can be started by user using calibration menu and selecting the internal calibration optio
10. the balance on a suitable and stable surface Take off the cover of the balance Do not unplug the display cable Mount the pan on the pan supports Locate the hexagonal screws to adjust the eccentric loading Always adjust for the largest differences first i e either the difference in value when the mass is placed at back to front or that of side to side whichever difference is the largest should be adjusted first e Re check the readings after each adjustment For small corrections the bolts will be turned by very small angles e The value of the mass used for adjustment should be of 1 3 to Y2 of the balance capacity e When placing the mass on the pan locate it at 1 2 the distance from the centre to the edge Refer to the following instructions for details A When the difference is greater in case of back to front of the pan than that of side to side do the front to back adjustment first Adam Equipment Company 2007 16 If the reading is more at the front If the reading is more at the back turn turn both the screws clockwise by both the screws anti clockwise by the the same angle same angle B When the difference is greater in case of the mass placed from side to side than that of the mass placed from back to front do the side to side adjustment first If the reading is more at the right side If the reading is more on the left side of of the pan turn the left screw anti the pan turn the left screw
11. the balance up side down and remove the 2 front screws using the 3mm Allen Hex Keys Step 4 Next you will need to remove the top saddle by removing the two screws using the 3mm Allen Hex Keys Remove the pan support spacers At this stage the balance is ready to be opened as shown in the next step Step 5 Press the spirit level lug downwards with one hand and lift the top case with the other hand Spirit Level Lug Step 6 To detach the top case Display remove the Display Cable and the Cable Keypad Cable from the main PCB Keypad Cable Step 7 To detach the top pan support bracket from the Mechanics use the 3mm Allen Hex Keys to remove the 2 screws Top pan support bracket You can view the Mechanics with the top horizontal flexures and the magnet Flexures with cover Magnet cover Mechanics Adam Equipment Company 2007 20 Magnet Cover Sguare Tool Ff HEI UE M Adam Equipment Company 2007 21 Step 8 If you need to clean the Drive Coil and the magnet remove the 2 screws attached to the magnet cover using the 4mm Allen Hex Keys Step 9 Itis suggested to add the Square Tool at this stage to protect the flexures from getting damaged during any repair work Step 10 Unsolder the Drive Coil Wires Note the position of the coll drive wires on the board to remove the mechanics from the case If not re connected correctly the balance will not work Step 11
12. with these balances leading to inaccurate weighing are generally of the following types a Calibration and Linearity faults b Mechanical faults c Electronics faults A general troubleshooting section follows in section 4 0 In order to know if a balance is working properly it will be necessary to carry out some performance tests on the balance See section 5 0 for the details A brief description of the mechanical adjustments is covered in section 6 0 In most cases the first thing to be considered as a part of trouble shooting is the software parameters as this is the main method used to set calibration and linearity set parameters view temperatures sensor values and perform the most basic of calibration functions See section 7 0 to enter the Dealer Parameter Settings Faults associated with these balances leading to inaccurate weighing are generally of the following types a Calibration and Linearity faults See section 5 0 amp 7 0 b Mechanical faults See section 6 0 c Electronics faults See the note below NOTE The Electronics modules within the balance are not serviceable In case of any electronics component failure contact your supplier Adam Equipment Company 2007 9 4 0 TROUBLE SHOOTING GUIDES service of a balance will generally be necessary when the balance does not perform as expected The balances are not user serviceable Problems usually fall into one of the following categories User Problems
13. 12 FUNCTIONAL TESTS AND ADJUSTMENTS In order to know if a balance is working properly it will be necessary to carry out the following tests on the balance These tests should be performed initially when it is not clear whether there is any problem with the balance These tests should also be performed anytime a balance has been serviced or any changes are made Before performing the tests the balance should be allowed to warm up in a stable environment for a minimum of 4 hours During this time the following should be checked e Install the pan supports the pan and the breeze shield if applicable and make sure they do not interfere with correct weighing e Level the balance e Verify all the keys work properly and the functions set are suitable for the balance to be tested For example set to grams weighing all digits operating normally the filters set to a normal setting etc e Verify the RS 232 is operating correctly using a communications program e Verify the display is correct the minus sign is shown decimal points are in the correct position the weighing unit is correct and the stability symbol is correct e Verify the calibration is functioning correctly For better accuracy we suggest to use only the Class F1 weights during the linearity adjustment The maximum permissible errors of F1 weights are given in the Table below TABLE 3 OIML R 111 TEST WEIGHT TOLERANCES Value of Class Maximum Value of Class M
14. 6461 6236 Fax 44 0 1908 641339 Fax 1 203 792 3406 Fax 27 0 11 392 2587 Fax 61 0 8 9456 4462 E mail E mail E mail E mail sales adamequipment co uk sales adamequipment com sales adamequipment co za sales adamequipment au com Copyright by Adam Equipment Co Ltd All rights reserved No part of this publication may be reprinted or translated in any form or by any means without the prior permission of Adam Equipment Adam Equipment reserves the right to make changes to the technology features specifications and design of the equipment without notice All information contained within this publication is to the best of our knowledge timely complete and accurate when issued However we are not responsible for misinterpretations which may result from the reading of this material The latest version of this publication can be found on our Website Visit us at www adamequipment com Adam Equipment Company 2007 32
15. Assembly Assembly Lower Horizontal Beam Horizontal Flexure Adam Equipment Company 2007 35 ANNEXURE TABLE 14 PGW SELECTED PART NUMBERS Display PCB 6095 Power PCB includes RS 232 7068 Flexures for PGW 153 253 4538753 TI Puller x 1 8663 Pivots x 2 Pivotsx2 00 Flexures for PGW 1502 2502 3502 amp 4502 Horizontalx8 S Horizontal x 8 Pan Support Bracket for PGW 153 253 453 amp 753 Pan Support Bracket for PGW 1502 2502 3502 amp 4502 Rubber Pan Support set of 4 Anti static Springs Circlip circular clip to retain the pan support in place Return Spring Optical Position Sensor complete assembly Power Cable NOTE Refer to the drawings for the item number corresponding to this list If spare parts are required identify the model number and serial number of the balance Contact your supplier for further details on price and availability of all spare parts The circuit boards do not have user serviceable parts Adam Equipment Company 2007 36 CE Manufacturer s Declaration of Conformity This product has been manufactured in accordance with the harmonised European standards following the provisions of the below stated directives Electro Magnetic Compatibility Directive 89 336 EEC Low Voltage Directive 73 23 EEC Adam Equipment Co Ltd Bond Avenue Denbigh East Milton Keynes MK1 1SW United Kingdom FCC COMPLIANCE This equipment has been tested and found
16. Balance programmin correctly prog H A complete inspection of the mechanics to look for sources of friction Verify the A D is also unstable If the A D is OK then suspect the programming of the balance Reset parameters check temperature compensation and redo the Electronic problems calibration Some electronic problems can also cause this But all mechanical problems must be resolved first BALANCE IS NOT ACCURATE You must have accurate and trusted weights to test a balance If you suspect that the balance is not accurate then you must know your weights are accurate A balance calibrated using a bag of flour is not accurate even if it works OK otherwise Balance is not accurate Repeatability Verify the balance shows the same value when the same mass is placed on the centre of the pan for a few tests ecentiio 0agIng Verify the balance shows the same reading within a tolerance depending upon the model when a mass is placed at positions around the pan Linearity Verify the balance is acceptable throughout the weighing range The balance must give acceptable readings from low weights up to the capacity Poor Repeatability Usually a mechanical Inspect the area around the pan for hair problem dust or other obstructions Inspection of the mechanics may be Adam Equipment Company 2007 11 needed for any possible problems Poor Eccentric loading A mechanical problem Inspect the area around the pan for ha
17. HEW DOW Ores pied Cable Connector Check adapter is correct for the balance fallure Normal adapter is 15VDC 800mA Power supply circuit board failure Short circuit on any circuit board The display does not turn Power is getting to Display cables may be faulty on but the calibration balance display is not motor moves when working power is applied Display module failure Adam Equipment Company 2007 10 The display stays onthe Unstable balance Check if balance is stable by using service initial test screen when power is applied Calibration weight motor is ON Power supply Check power supplies menu and view A D values Balance not working enu and correct Put draught shield over pan BALANCE WORKS BUT IS NOT STABLE Balance is unstable by a Noise or vibration from Check the balance is positioned correctly to few divisions environment avoid vibration wind or air movement It is on a solid table It is not near sources of Friction in mechanics heat or cool air Check balance with weights if problem occurs when sample is used Static electricity on the samples can cause drifting and instability Check the area around the weighing pan for hair dust obstructions under the pan A complete inspection of the mechanics to look for sources of friction may be needed Balance is very unstable Mechanical problems Check whether the temperature is changing and does not weigh or there is a draught
18. Hazardous Waste Regulations 2005 Battery recycling has become topical and the Waste Electrical and Electronic Eguipment WEEE Regulations are set to impose targets for recycling Adam Equipment Company 2007 37 ADAM EGUIPMENT is an ISO 9001 2000 certified global organisation with more than 30 years experience in the production and sale of electronic weighing eguipment Products are sold through a world wide distributor network supported from our company locations in the UK USA SOUTH AFRICA and AUSTRALIA ADAM s products are predominantly designed for the Laboratory Educational Medical and Industrial Segments The product range is as follows Analytical and Precision Laboratory Balances Counting Scales for Industrial and Warehouse applications Digital Weighing Check weighing Scales High performance Platform Scales with extensive software features including parts counting percent weighing etc Crane scales for heavy duty industrial weighing Digital Electronic Scales for Medical use Retail Scales for Price computing Adam Equipment Co Ltd Adam Equipment Inc Adam Equipment S A Pty Ltd Adam Equipment S E ASIA Bond Avenue 26 Commerce Drive 7 Megawatt Road Pty Ltd Milton Keynes Danbury CT Spartan EXT 22 Kempton Park 2 71 Tacoma Circuit MK1 1SW 06810 Johannesburg Canning Vale Perth UK USA Republic of South Africa Western Australia Tel 44 0 1908 274545 Tel 1 203 790 4774 Tel 27 0 11 974 9745 Tel 61 0 8
19. Must be done Adam Equipment Company 2007 24 7 0 DEALER PARAMETERS The parameters available to the users are described in the User Manual in details This section describes the parameters available to the dealers for setting up the balance Access to these parameters is controlled by password From the supervisor menu select the PASSCODES option From the PASSCODES menu select the OPERATOR option Enter the dealer passcode which is 41218 DLR as D 4 L 12 R 18 letter of the alphabet Press Setup Enter Press the Mode key three times or press the Esc key to return to weighing and then the Setup Enter key to return to the outer level menu which now displays SUPERVISOR From this menu select the DEALER option Available options on the dealer menu are 1 ADC COUNTS The balance displays the averaged temperature compensated and linearity corrected weight ADC counts in the small digits and the spread of the last 50 readings in the large digits Pressing the Unit key switches the display between the weight and temperature ADC counts Temperature counts display is indicated by a T symbol and shows the individual temperature ADC counts in the small digits and the average of the last 10 readings in the large digits Pressing the Setup Enter or Mode key escapes to the next item on the dealer menu Pressing the Esc key returns to weighing TABLE 10 WEIGHT ADC me em Zero Setting
20. Next you will need to remove the bottom case Turn the balance up side down and remove the 3 screws using the 3mm Allen Hex Keys Step 12 Lift the case carefully leaving the mechanics on the work surface Step 13 If you need to change any of the flexures hold the assembly firmly as shown Remove the damaged flexure by using the 3 mm Allen Hex Keys and fix the new one Fix the assembly back into the base when complete lf you need to replace any flexure the following guidelines may help Replace only with the correct flexure procured from Adam Equipment See table 1 for details If possible only replace one flexure at a time Keep all flexures aligned vertically horizontally and from front to back The active area of a flexure must align with the active area of all other flexures in the same axis Do not over tighten the flexure screws Residual stress is often a cause of drift with temperature or unstable readings When tightening the screws work slowly from one screw to the others to tighten all screws a little at a time Do not allow the flexures to twist when tightening the screws Be certain you are using the correct flexures for the balance Many flexures look very similar but have different applications The major difference between similar flexures is the thickness of the active area Be very careful not to bend flexures during installation Remember flexures are designed to be very weak in the direction they bend
21. They are not strong enough to support a large weight in the bending direction Adam Equipment Company 2007 22 Step 14 To have the access to the Puller and vertical flexures the Power Board and the back panel needs to be removed Remove board by using 3mm Allen Hex Key as shown here Step 15 Next pull out the back panel holding with both the hands Step 16 The Puller Flexure can then be accessed for repair as shown here Vertical Use the 3mm Allen Hex Key Flexure Puller Flexure Step 17 After all repair work is done follow the steps backwards to re assemble the balance Remove the cap covering the weigh below hook by lifting it from the base Step 18 While fixing back the bottom case use the weigh below as a reference for correct alignment Adam Equipment Company 2007 23 Step 19 Ensure the weigh below is in the exact centre of the hole provided for installing the hook Step 20 After the repair it is suggested that the balance is Temperature calibrated using a Constant Temperature Chamber or in a suitable room particularly for few cases as described in Table 9 PGW Inside a Constant Temperature Chamber TABLE 9 GUIDELINE FOR TEMPERATURE COMPENSATION REPAIR UNDERTAKEN REMARKS ON TEMP COMPENSATION Not required Not required Eccentric Loading adjusted Not required Must be done Temperature sensor replaced Must be done Data erased or amended Must be done PCBs replaced
22. ature variations in the mechanism The balance is tested and calibrated at extreme temperatures and the details are stored in the memory These details are used to compensate for temperature changes inside the balance due to self heating and ambient conditions The internal calibration models include an internal calibration weight controlled by the microprocessor This weight is not accessible by the user Calibration can be performed when the temperature sensor detects a change in the pre set temperature or the pre set time either automatically or by manually entering in to the Calibration Menu Adam Equipment Company 2007 4 ELECTRONICS MODULES Within the balance there are electronic modules for e Main PCB assembly including analogue circuit e Interface PCB assembly includes power supplies 8 RS 232 circuits e Display PCB e Calibration motor system for internal calibration models PRINCIPLES OF BALANCE MECHANISM 8 Current to Coil KE Calibration CM R or Mass pl n Current LLL OR Temperature Sensor RS232 LIProcessor V kr all Filter kr all S WLLL Details of the operation of the balance are found in the PGW User Manual Adam Equipment Company 2007 5 2 2 MODEL DIFFERENCES The PGW Series of balances have capacities that vary from 150g to 4500g The basic electronics and software are identical the only differences between the models are Value of current sense
23. aximum F1 weights Permissible Error F1 weights Permissible Error 5000 g 0 025 g 100g 0 0005 g 2000 g 0 010 g 50g 0 0003g 1000 g 0 005 g l20g 0 25mg 500 g 0 0025 g l10g 0 020 mg 200 g 0 0010 g I Pe 5 1 REPEATABILITY TESTING AT INTERNAL CALIBRATION MASS Repeatability is checked at the approximate value of the internal calibration mass Perform automatic calibration Place the right weighing mass on the pan as shown in the table below Repeat this procedure 5 times Compare the reading results with the actual mass Compare results the readings with the mass on the pan should agree within the acceptable error as shown Adam Equipment Company 2007 13 TABLE 4 REPEATABILITY ERRORS AT INT CAL MASS Balance model Mass Acceptable error PGW 153 100g 0 002 g PGW 253 240g 0 002 g PGW 453 240g 0 002 g PGW 2502 1400g 0 02g PGW 3502 1400g 0 02g PGW 4502 1400g 0 02g 5 2 REPEATABILITY TESTING AT FULL CAPACITY PGW 753 520g 0 002 g PGW 1502 1400g 0 02g e Place the mass on the pan as shown in the table below e After stabilization record the reading e Take off the mass and after stabilization record the reading with no mass on the pan e Repeat 5 times e Compare results the readings with the mass on the pan should agree within the acceptable error as shown TABLE 5 REPEATABILITY ERRORS AT FULL CAPACITY Balance model Mass__ Acceptable error GD 0 002 g
24. ble Pressing the Mode key at any time escapes back to the LINEAR CAL menu option Pressing the Esc key at any time returns to weighing If any measurement errors are encountered an appropriate error message will flash on the display until any key is pressed when the instrument will return to the LINEAR CAL menu option If any error is encountered or the Mode or Esc keys are pressed during linearity calibration the procedure will be aborted with no new data stored and any previous linearity calibration data will be retained Adam Equipment Company 2007 27 TABLE 12 MASSES NEEDED FOR LINEARITY CALIBRATION BALANCE MASSES FOR LINEARITY CALIBRATION MODEL PGW 153 PGW 253 50g 100g 150g 100g 200g 300g PGW 2502 200g 400g 600g up to 2700g 250g 500g 750g up to 3750g 8 0 INTERNAL CALIBRATION MASS ADJUSTMENT TABLE 13 LIST OF INTERNAL CALIBRATION WEIGHTS e 240g 240 NOTE The value of the internal mass is not an exact number such as 100g It must be set by comparing with an external mass The exact value can be set using the Supervisor Parameter seciion as described in the User Manual section 13 5 provided this feature is enabled at the factory PROCEDURE e Make sure the balance is level and has been ON for 4 hours or more at a stable temperature e Calibrate the balance twice This helps to reduce any stresses in the mechanics e o verify the accuracy of this internal ca
25. clock wise clockwise and the right screw and the right screw anti clockwise by the clockwise by the same angle same angle After setting the adjustment you should place the balance to one side for some time and weigh on it occasionally This helps to reduce the internal tensions Re test again and continue adjusting if necessary 5 4 LINEARITY TESTING e Place the weights on the balance covering the balance range from min to max as suggested in the table Typical line er below a Check deviations of the displayed Ideal line play oa e values from the actual values on the Fa weights on pan Linearity Error e If necessary re calibrate Ensure the environment is stable the warm up time is as specified and only the Class F1 weights are used during calibration e Check accuracy of linearity If the values are still not acceptable contact your supplier Adam Equipment Company 2007 17 Examples of the weights that can be used for testing are given in the following table TABLE 7 SUGGESTED MASS FOR THE LINEARITY TESTING p wiss 109 200 509 409 500 609 609 109 09 509 PGW 1502 100g 200g 300g 400g 500g 600g 800g 1000g 1200g 1500g PGW 2502 500g 600g 800g 1000g 1200g 1500g 1700g 2000g 2200g 25009 PGW 3502 500g 600g 800g 1000g 1200g 1500g 2000g 25009 3000g 35009 PGW 4502 500g 1000g 1200g 1500g 2000g 2500g 3000g 3500g 4000g
26. elect YES by pressing the Enter key The value of the internal mass set in the factory will be displayed e A new internal value can then be reset to make the external mass value display correctly If the reading for the external mass is greater than the actual value of the mass then reduce the internal mass value by the difference Enter this reduced value when prompted by the display For example if the internal mass previously set is 520 054g and the display reads 500 050g when using an external mass of 500g then reduce the internal mass value by 0 050g Enter the new revised value of 520 004 in place of 520 054g when prompted The adjustment can be done for up to 100mg e Repeat the calibration and check the value of the external mass again e Repeat this procedure until the value displayed is correct for the mass used e Press Esc to return to normal weighing Adam Equipment Company 2007 29 9 0 CABLES AND CONNECTIONS ker prose seal 3 R za EL E E EE Interface FCB Internal Calibration bitor Sesembliy Power Adam Equipment Company 2007 30 10 0 BALANCE MENU DIAGRAMS WEIGHING OPERATOR PW PGW MENU STRUCTURE Software Version 2 41 Okey Standby Operation O T key Zero Tare Print key Serial output in selected format if enabled Unit key Select enabled units Cal key Calibration if enabled Internal if enabled External Mode
27. em using a method of applying the force from the unknown mass on one end of a beam and balancing it with the force generated due to the current in the coil on the opposite end The balance position is detected by an optical detector connected to the beam When the mass is placed on the balance pan the beam will be moved out of its original null position This movement is detected by the optical sensor An amplifier connected to the sensor will change the current through the coil to force the beam to go back to its null position The amount of change in the current through the coil is proportional to the unknown mass on the pan The current passes through a precision resistor creating a voltage that is measured by the A D converter Mechanical parts surrounding the balance beam make the force generated due to the unknown mass go in a Straight line through the balance beam thus eliminating any differences depending upon the location of the mass on the balance weighing pan The electronics measure the voltage using precision amplifiers A D converter with high resolution and a microprocessor working with memory displays and power supply The microprocessor uses information from the A D converter a separate temperature sensor amp A D converter for measuring the magnet temperature and the internal program to determine the weight of the unknown mass and all other information to be displayed The system uses special programs to correct any temper
28. gt 500 000 0 5 to 1 5 million Maximum Linearity Load lt 16 000 000 14 16 million See Table 8 Adam Equipment Company 2007 25 TABLE 11 MAXIMUM LINEARITY LOAD BALANCE MODEL MAXIMUM LINEARITY LOAD PGW 153 160g PGW 253 260g PGW 453 475g PGW 753 800g PGW 1502 1600g PGW 2502 26009 PGW 3502 37509 PGW 4502 47509 2 DATA COMMS e Displays ACTIVE when selected e Pressing the Print key sends the stored configuration data as a formatted table with address headers to the RS 232 port at 9600 baud 8 bits no parity irrespective of the settings chosen in serial setup on the supervisor menu e Pressing the Setup Enter or Mode key escapes to the next item on the dealer menu e Pressing the Esc key returns to weighing 3 CALIBRATE This menu offers two options A TEMP CAL e Select the LOW or HIGH temperature calibration point e Enter the balance temperature 10 to 40 deg C e f the low temperature calibration point is selected the entered temperature must be at least 10 degrees below the one stored for the high temperature calibration point otherwise the display will show ERROR HI e f the high temperature calibration point is selected the entered temperature must be at least 10 degrees above the one stored for the low temperature calibration point otherwise the display will show ERROR LO e f the entered temperature is within range the display will show the message LOAD 0
29. ir dust or other obstructions Inspection of the mechanics may be needed for any possible problems Readjusting of the Eccentric loading is recommended Poor Linearity Usually a mechanical Re check repeatability problem Inspection of the flexures for damage or loose hardware may be reguired Use the Linearity Function in the service menu to reset linearity A problem in the analogue circuit board or power supplies can cause poor linearity Electronic Problems Make sure all mechanical problems have been eliminated first OTHER PROBLEMS Cannot calibrate Zero shifted more than Check all flexures for damage allowed Reset factory calibration Verify linearity and repeatability SEENEN The balance may be unstable Verify Stability as above Try using a more aggressive filter Calibration weight motor Check the cables to the motor try plugging does not stop the balance into the power again Look for friction in the calibration weight movement Check the opto coupler that controls the motor position RS 232 not working Doesn t print Check parameters match the device connected Verify cable is correct RS 232 circuits damaged Display dark keys beep Display contrast poor Check the cables to the display Cable damaged Replace display it may be damaged LCDs on the display are faulty or damaged To be carried out by authorised technicians only 5 0 Adam Equipment Company 2007
30. libration place an external mass approximately equal to the same internal calibration mass Record the result Adam Equipment Company 2007 28 e Enter the Internal Calibration section using the Supervisor passcode as per the following procedure e Pressing the Setup Enter key while in normal weighing gives access to the Supervisor Menus e When Setup Enter is pressed and passcodes are not enabled the display will show the Supervisor menus If passcodes are enabled the balance will ask for it by displaying PASSCODE O e Ifa wrong code is entered an ERROR CODE message will flash and the balance will return to weighing mode e lf the passcode has been enabled and entered the balance will allow the user to access the Supervisor s menus by which the user can enable disable weighing units or modes set balance parameters for the conditions set time and date set parameters for the RS 232 interface calibration parameters and security parameters e The display will show the first menu UN TS The Up and Down keys will cycle through the main menus pressing the Setup Enter key will enter the menu and sub menu or options can be set Press Mode to come out of a sub menu or Esc to return to normal weighing e Press Enter when CALSETUP is displayed to select the calibration parameters e The options for each parameter can be scrolled through by using the Up or Down key e When INT CAL is displayed s
31. n or automatically when the time or temperature of the system changes by a pre set value with respect to the time or temperature of last calibration Automatic Calibration function can be disabled by the user in the calibration sub menu Adam Equipment Company 2007 7 2 4 EQUIPMENT AND TOOLS REQUIRED The following tools and equipment may be helpful when working on the balance GENERAL TOOLS AND EQUIPMENT Screwdriver Philips Screwdriver Medium Flat Allen Hex Keys 3mm 4mm Needle Nose Pliers Soldering iron Precise square Slide calliper magnifier X10 Voltmeter Oscilloscope SPECIAL TOOLS AND EQUIPMENT Weighing mass OIML Class F1 Suitable place for temperature tests Adam Equipment Company 2007 Calibration and test masses should be used that will cover the weighing range of thee balance to be tested The masses should be of high accuracy or the actual mass should be known if less accurate masses are used A Constant Temperature Chamber or alternatively a room capable of holding a steady temperature of 1 C and a differential temperatures of minimum 10 C and have a suitable table or platform for the balances to be stable for performing the temperature compensation This is required if the memory is cleared wrong temperature compensation values are used or if the magnet has been modified Repair of flexures normally do not require temperature compensation See Table 9 details 3 0 COMMON FAULTS Faults associated
32. ne only by Service Personnel trained and approved by Adam Equipment FEATURES e Large easy to read LCD display with backlight e Standard applications include Weighing Check weighing Percentage Weighing Parts Counting Animal Dynamic Weighing Net Total and Density Determination e Internal Calibration using motorised internal calibration weight e External calibration models available e Bi directional RS 232 interface e Can be configured to print a GLP Compliant PGW series report after each calibration to include the time date balance number and a verification of the calibration Automatic temperature compensation Display in 4 languages English French German and Spanish 18 weighing units Capacity tracker Date and time Easy to use sealed keypad Below balance weighing facility Password protection security locking point Robust metal casing Adam Equipment Company 2007 3 2 0 DESCRIPTION OF CONSTRUCTION 2 1 PRINCIPLE OF OPERATION The PGW balances use an electro magnetic force restoration or force motor type mechanics that converts a force generated due to an unknown mass placed on the weighing pan into a voltage which can be measured by a high precision voltmeter The force restoration system uses a magnet section along with a coil to convert a current through the coil into a force This force will balance the force caused due to the unknown mass on the balance pan This is accomplished in a syst
33. to comply with the limits for a Class A digital device pursuant to Part 15 of the FCC Rules These limits are designed to provide reasonable protection against harmful interference when the equipment is operated in a commercial environment The equipment generates uses and can radiate radio frequency energy and If not installed and used in accordance with the instruction manual may cause harmful interference to radio communications Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his own expense Shielded interconnect cables must be employed with this equipment to insure compliance with the pertinent RF emission limits governing this device Changes or modifications not expressly approved by Adam Equipment could void the user s authority to operate the equipment WEEE COMPLIANCE 7 Sealed Lead Acid Battery e Must be recycled Properly Any Electrical or Electronic Eguipment EEE component or assembly of parts intended to be incorporated into EEE devices as defined by European Directive 2002 95 EEC must be recycled or disposed using techniques that do not introduce hazardous substances harmful to our health or the environment as listed in Directive 2002 95 EC or amending legislation Battery disposal in Landfill Sites is more regulated since July 2002 by regulation 9 of the Landfill England and Wales Regulations 2002 and
Download Pdf Manuals
Related Search