Home

Operation and Maintenance Manual

1. a pae ut 38 FIGURE 7 1 GASMAX SENSOR REPLACEMINT si Nee a up Ov E 40 FIGURE 7 2 SMART SENSOR RECOGNITION SCREEN RR EE 40 FIGURE 5 1 11 10 1161 42 FIGURES 2 SYSTEM CON EG MENU 0 7 7 0 9 43 FIGURE 8 3 SENSOR LIFE TRANSMISSSION etu oru nuda 45 FIGURE 2 18 ES bustum 45 462 MODBUS ntn t n vetant t vt ante a aua E 46 FIGURE S5 SENSOR SETHNGS MENU eon ie Pane ate Sia it eee de 47 FIGURE S7 CLOCK DELAY IVIEN U on oni ica eon iue o eod ae 47 FIGURE 95 8 CONTRAST MENU 48 8 GASMAX II Operation amp Maintenance Manual Revision 4 0 FIGURE 35 9 DIAGNOSTICS
2. 65 FIGURE 19 77 WITH Y ADAPTE R 66 FIGURETTA T GASMAX DIMENSIONS ear pna eg ban 67 FIGURE 14 2 GASMAX DUAL LOCAL SENSOR 1 4 44 4444400 67 Page 9 GASMAX II Operation amp Maintenance Manual Revision 4 0 Important Read Before Installation Users should have a detailed understanding of GASMAX operating and maintenance instructions Use the GASMAX II only as specified in this manual or detection of gases and the resulting protection provided may be impaired Read the following WARNINGS prior to use WARNINGS e The GASMAX II gas monitor described in this manual must be installed operated and maintained in accordance with information contained herein Installation in any hazardous area must comply with all applicable restrictions requirements and guidelines for said hazardous areas It is the end user customer s final decision to ensure that the GASMAX is suitable for the intended use e The GASMAX II is designed and constructed to measure the level of certain gases in ambient air Accuracy in atmospheres containing steam or inert gases cannot be guaranteed e Always mount the sensor head vertically with the sensor head facing down However the GDS IR infrared sensor may be mounted vertically or horizontally e Donot paint transmitter or sensor as
3. mmo a mimm mn a 4965 WA a WA 0000 6 mma 3 NA mus a mms a NA mi mmcmma a mm 3 6 9969 3 mi wmomeDwer mmm a WA mm 3 WA 2 wal Page 56 GASMAX II Operation amp Maintenance Manual Revision 4 0 Ch 1 A2D MIN 41041 Min and max points for A D and D A Ch 2 D2A MAX CHANNEL STATUS WORD BIT DEFINITION ar a alarm O 4 a 3 9 39 m 9 93 Tats compensation 8 ro temp como 0 ____ o 1 si no displey neeatwe 0 57 GASMAX II Operation amp Maintenance Manual Revision 4 0 12 Transmit Sensor Life 1 transmit sensor life 0 ALARM STATUS WORD BIT DEFINITION ma
4. Channel Data CRC Fail Error in sensor data transfer Contact factory e 08 Data CRC Fail Error in system data file Contact factory e 09 Custom Data CRC Fail Error in system data file Contact factory e 10 Linearization Data CRC Fail Error in system data file Contact factory SOFTWARE RESET COLD BOOT If the GASMAX display shows nonsense characters or one or more of the settings appear to be corrupted performing a Cold Boot will restore the default values in the non volatile memory and may clear the problem To perform a Cold Boot perform one of the two following procedures Disconnect power Hold a magnetic wand over the EDIT key and apply 24VDC power Hold the magnet until the screen shows a COLD BOOT message e Hold the magnetic wand over the NEXT key until the Enter code sequence appears Press four UP keys to enter the XMITTER menu Make a change in any value and then restore the value to its original setting Press the NEXT key to exit and THEN IMMEIDATELY PLACE THE MAGNETIC WAND OVER THE EDIT KEY Hold the magnet until the screen shows a COLD BOOT message Note that a COLD BOOT will reset certain values to their default setting including the MODBUS address value If a Smart Sensor is connected to a local sensor head the GASMAX will reload the sensor type range cal span value and other sensor related values automatically Page 61 GASMAX II Operation amp Main
5. SENSOR CONNECTION 21 FIGURE 4 10 LOCAL SMART BRIDGE SENSOR 0 4404400 23 FIGURE 4 11 REMOTE BRIDGE SENSOR CONNECTION 1 0 0 24 FIGURE 4 12 REMOTE SENSOR TRANSMITTER 25 FIGURE 4 13 GASMAX WITH EOCAL 26 FIGURE 4 14 REMOTE GDS IR CONNECTION 6 Ea oae gue v ea aen 27 4 15 2 2 6 28 FIGURE 4 16 DUALA 20MA INPUT OPTION i a oe eee 29 FIGURE 5 5 1 GASMAX DATA DUAL CHANNEL AND TREND 32 FIGUIRE 5 5 2 GASIVIAX DATA DISPLAY catia e eoe ie uo East Mert dei aa deos ande dde mae ot 33 HOGURE 5 5 3 GASMAX TREND DISPLAY tin nte E ee 34 FIGURE 5 5 4 GASMAX DUAL CHANNEL DISP EAY in ne no aere ea Uo 34 FIGURE 5 5 5 GASMAX DISPLAY SEQUENCE SINGLE CHANNEL eene nennen 34 FIGURE 5 5 6 GASMAX DISPLAY SEQUENCE DUAL 35 FIGURE 5 F CALIBRATION EEO WCPEART 55
6. G Do 5 M Gas and Flame Detection Operation and Maintenance Manual GASMAX II Single Dual Channel Gas Monitor GDS Corp 1245 Butler Road League City TX 77573 409 927 2980 409 927 4180 Fax ww gdscorp com GASMAX II Operation amp Maintenance Manual Revision 4 0 CAUTION FOR SAFETY REASONS THIS EQUIPMENT MUST BE OPERATED AND SERVICED BY QUALIFIED PERSONNEL ONLY READ AND UNDERSTAND INSTRUCTION MANUAL COMPLETELY BEFORE OPERATING OR SERVICING ATTENTION POUR DES RAISONS DE SECURITE CET EQUIPEMENT DOIT ETRE UTILISE ENTRETENU ET REPARE UNIQUEMENT PAR UN PERSONNEL QUALIFIE ETUDIER LE MANUE D INSTRUCTIONS EN ENTIER AVANT D UTILISER D ENTRETENIR OU DE R PARER L QUIPEMENT REVISION HISTORY Hevision 3 5 4 10 3 14 Minor revisions amp corrections Revision 4 0 0 12 8 14 Major revision Copyright 2014 GDS Corp All Rights Reserved P N 1200 0851 04 Page 2 GASMAX II Operation amp Maintenance Manual Revision 4 0 1 SAFETY INFORMATION 10 2 OVERVIEW 11 GASMAX Sensors 11 3 HARDWARE 212 4 INSTALLATION 13 Selecting a Location 13 Mounting the GASMAX 13 Mounting a Remote Sensor 13 Explosion Proof Installation 14 Intrinsically Safe Installation 14 Connecting DC Power amp Output Signal Wiring 15 Optional Relay MODBUS Interface 15 Relay Functionality 16 MODBUS Wiring 16 Optional Dual Isolated 4 20mA Output Board 19 Local SMART Toxi
7. GASMAX II Operation amp Maintenance Manual Revision 4 0 Figure 5 5 3 GASMAX Trend Display The TREND display shows a graphical representation of the most recent 30 minute trend The Alarm 1 level is shown as a closely spaced dotted line and the Alarm 2 level is shown as a widely spaced dashed line Figure 5 5 4 GASMAX Dual Channel Display When operating in dual channel mode an additional display option is available that shows both channels calibrated values and engineering units Measurement name values are not shown In addition to the right of each value there are indicators for Alarm 1 A1 Alarm 2 A2 and Fault To switch between displays use the NEXT key In single channel mode pressing the NEXT key will switch between the DATA screen and the TREND screen In dual channel mode pressing the NEXT key will sequence through five screen options as shown in Fig 2 5 X LEL Emm MEASUREMENT NAME Figure 5 5 5 GASMAX Display Sequence Single Channel Page 34 GASMAX Operation amp Maintenance Manual Revision 4 0 MEASUREMENT NAME m EASUREMENT NAME Channel 1 Channel 2 Channel 1 Trend Channel 2 Trend Dual Channel Figure 5 5 6 GASMAX Display Sequence Dual Channel ALARM OPERATION ALARM 1 AND 2 GASMAX II gas monitors have front panel LED indicators for ALARM 1 and ALARM 2 Both alarm indicators can be set to activate above or below a given engineering units set point Alarm
8. s characteristics as a result of shipping and installation INITIAL BRIDGE SENSOR VOLTS CHECK Bridge sensors require specific excitation voltages to operate properly This voltage must be measured at the Remote Sensor Head Junction Box between points R and A When shipped from the factory the GASMAX excitation voltage will be SensorType Voltage Current Warmup preset for the type of bridge sensor specified Catalytic Bead 7 see Sensor Type table However this SmartlR Type 5 voltage may need to be increased to PID Type 6x compensate for voltage drop in the sensor cable NOTE IF YOU ARE NOT CERTAIN THAT SENSOR VOLTAGE IS ADJUSTED PROPERLY DISCONNECT THE REMOTE SENSOR BEFORE APPLYING POWER TO THE GASMAX MONITOR ADJUST SENSOR EXCITATION VOLTAGE AS SHOWN IN THE TABLE ABOVE AND THEN CONNECT THE REMOTE SENSOR To adjust sensor excitation voltage access the Technicians Menu see Section 8 2 Select Set Voltage and use the UP and DOWN keys to set the voltage Keep in mind that the voltage at the GASMAX R and A pins may need to be higher than the value measured at the sensor head to compensate for voltage drop in the cable WARNING EXCEEDING A SENSOR S EXCITATION VOLTAGE WILL DAMAGE OR DESTROY THE SENSOR INITIAL BRIDGE SENSOR BALANCE CHECK Bridge type sensors typically require a balance adjustment after installation or if the sensor has drifted too far for zero cali
9. Each item s description follows in this section SYSTEM CONFIG PG 1 SYSTEM CONFIG PG 2 A Bvicasurement Name 16 UP Readout Deadband 0 Eunits XXXXXXXXXX 10 Track Negative NO Zero 0 Eunits Temp Compensation Span 100 Eunits Backup Config m E Restore or Upl vad Restore available only Decimal Points ES Cal Marker n om without smart sensor installed Cal Span Val TX Sensor Life Upload available only with smart sensor installed Figure 8 2 SYSTEM CONFIG MENU MEASUREMENT NAME may be edited to contain virtually any 16 character field and is typically used to describe the monitored point by user tag number or other familiar terminology To modify the existing setting press the EDIT key when the cursor is pointing to the entry Use the UP or DN keys to change the character and the NEXT key to move to the next character Press EDIT again when done EUNITS engineering units may have up to a 10 character ASCII field Many common gases have pre configured Eunits based upon the sensor type and each may be edited in this menu as described in Configuration Using the Magnetic Wand section 5 2 ZERO 0 defines the reading to be displayed when 4mA 0 is the GASMAX II output SPAN 100 defines the reading to be displayed when 20mA 100 is the GASMAX output The highest reading allowed is 9999 including negative polarity sign Polarity is only indicated for negative readings DECIMAL POIN
10. K3 MODBUS Relay Isolated 4 20mA 10 0234 10 0250 10 0250 Dual 4 20mA Output Figure 13 3 GASMAX Expansion Boards SENSOR HEAD ACCESSORIES Sensor Head Splash Guard 10 0198 Splash Guard Fits all sensor heads Sensor Head Flow Cell 10 0205 Flow Cell 1 8 NPT compression fittings g 20 02055 Other specify Splash Guard Flow Cell Figure 13 4 GASMAX Sensor Head Splash Guard amp Flow Cell Page 64 GASMAX II Operation amp Maintenance Manual Revision 4 0 REMOTE TOXIC OR BRIDGE SENSOR Remote Sensor Head Assembly 20 0126 Remote Toxic or Bridge Direct Type 5 6 20 0127 Remote Toxic Reactive Gas Type 7 8 Note Does not include sensor Figure 13 5 GASMAX II Remote Direct Sensor Head REMOTE TOXIC SENSOR TRANSMITTER 1 24V Remote Sensor Transmitter Head Assembly 20 0129 Remote Toxic Sensor Transmitter Type 24 25 20 0130 Remote Toxic S T Reactive Gas Type 26 27 Note Does not include sensor 4 20mA OUT SENSOR SENSOR Figure 13 6 GASMAX II Remote Sensor Transmitter Page 65 GASMAX II Operation amp Maintenance Manual Revision 4 0 DUAL LOCAL SENSORS Y Adapter 5 10 Power Supply 1 10 1200 Y Adapter for dual local sensor heads Sensor Head for Y Adapter 10 0247 12 Toxic or Bridge Direct Type 1 2 Sensor head with extended 12 cable 10 0247F 12 Toxic Direct Reactive Gas Type
11. Remote toxic sensors connect to the Channel 1 Simple Sensor input on the back of the Display Assembly as shown in Figure 4 6 Due to the small signal output from toxic sensors remote direct input toxic sensors should be mounted no more than 15 wire feet from the GASMAX II display Further the cable used should be three wire stranded with foil shield and should be run inside metallic rigid conduit GDS Corp recommends Belden B8771 The cable shield must be connected to an earth ground at ONE END ONLY GMII Display Backside S to J box S GMII Display Backside R to J box R Display Backside C to J box C Figure 4 9 Remote Toxic Sensor Connection IMPORTANT TOXIC SENSORS ARE SUBJECT TO ACCELERATED DETERIORATION IF POWER IS NOT SUPPLIED WITHIN 3 MONTHS OF SHIPMENT FROM GDS CORP Page 21 GASMAX II Operation amp Maintenance Manual Revision 4 0 CONNECTING A REMOTE TOXIC SENSOR TRANSMITTER CH1 GASMAX II monitors with remote mount toxic sensor transmitters are shipped in two pieces and sensor wiring must be installed by the end user When used with Channel 1 toxic sensor transmitters connect to the Channel One 4 20mA input on the right hand side terminal strip of the I O power supply board If the 10 0233 D4 dual 4 20ma input I O power supply board is installed in the GASMAX then the remote sensor transmitter is connected as shown below 24 is available on TB1 1 If the 10 0233 B4 br
12. Bead gt Hew Sensor Bl 284n84 Ans other EDIT to Accert Recent Cal 64 85 64 to Exit HEXT to Abort Sensor Life Ms CLOCK DELH SETUP CALIBRATION CATES B gt Tine 12 25 42 Record 22 of 22 Date 4222 04 CAL Date 9405704 Warm Ur Sec Cal Purge 166 LIPADONMM to scroll HEAT to ERIT CONTRAST SMART SENSOR Tyre Cat Bead E n E SMART SENSOR info menu only ean aran Hn available with Smart sensor installed HEXT to EXIT SH Born 14 65 64 a 1 AHY to Exit apu Haag ecu DIAGNOSTICS OUTPUT STIMULATOR nter Seauence zi i M to accese YP KEY REM aeree MM Eoi Quteut 4 8 mA diagnostic mode ae EDIT t hange NEXT key to Exit Hert Qs DM See Manual HELP Bui done SYSTEM SECURITY ACTUATE RELAYS Contact Secure Level LOW melee Lu Relay 2 OFF Pass Code Relay 3 OFF Unlocked WARNING Variables in the Technicians Only menu are critical for correct operation A thorough understanding of each variable is required READ amp UNDERSTAND THE MANUAL Technicians Only menus discussed in Section 6 Figure 8 1 MAIN MENU FLOWCHART Page 42 GASMAX II Operation amp Maintenance Manual Revision 4 0 SYSTEM CONFIGURATION PAGE The System Config group consists of two pages of menus as shown in Figure 6 2
13. Negative Bias Negative Negative Negative Negative Negative Negative Negative Negative Negative Negative Positive Positive Positive Hydrogen Sulfide Oxygen Carbon Monoxide Ammonia Nitric Oxide Ethylene Oxide Hydrogen Chloride Hydrazine Arsine Sulfur Dioxide Hydrogen Hydrogen Cyanide Phosgene Phosphine Hydrogen Fluoride Nitrogen Dioxide Ozone Chlorine ppm H2S Oxygen ppm CO ppm NH3 ppm NO ppm Eth O2 ppm HCL ppm 2 4 ppm Arsine ppm SO2 ppm H2 ppm HCN ppm COCI2 ppm PH3 ppm HF ppm NO2 ppm Ozone ppm 2 ZERO CAL VALUE should always be set to 0 RAW MIN MAX COUNTS is factory preset and should not be changed MARKER ACTIVE enables an input level monitor on the channel 2 input if the input is set to accept a 4 2 signal If Marker Active is set the YES the following actions may be programmed to occur when the input signal matches the Marker Level setting Page 53 GASMAX II Operation amp Maintenance Manual Revision 4 0 MARKER TX LED will cause the TX LED to illuminate if the 4 20mA input matches the Marker Level setting MARK LEVEL is the value at which the Marker is active The input must be within 1 of this value to be active Setting is in mA MARK AS MESSAGE is a text message string that appears on the LCD when the input level matches the Marker Level setting Page 54 GASMAX II Operation amp Maintenance Manual Revision 4 0 GASMAX II featu
14. Revision 4 0 SENSOR SETTINGS INFO 4 ERR INSTALL NEW SENSOR INSTALL NEW SENSOR B install Sensor gt EDIT to install Historical CAL data Recall Cal History gt New Sensor EDIT Will be Deleted Input Type SMART gt New Sensor 01 28 04 Any other key EDIT to Accept Recent Cal 04 05 04 to Exit NEXT to Abort Sensor Life m CALIBRATION DATES Record 22 of 22 CAL Date 04 05 04 UP DOWN to scroll NEXT to EXIT SMART SENSOR Type Cat Bead Span 100 Zero 0 SN XXXXXX Born On 01 28 04 Last Cal 04 05 04 ANY key to Exit Figure 8 6 SENSOR SETTINGS MENU INSTALL NEW SENSOR should always be performed when a new simple sensor is installed This deletes historical CAL data and sets sensor life to 10096 after initial calibration of the new simple sensor GASMAX II Smart Sensor interface will automatically detect new Smart Sensors and this menu is therefore not available with a Smart Sensor connected RECALL CAL HISTORY recalls each successful calibration These dates may be reviewed by scrolling with the UP DOWN keys INPUT TYPE indicates what kind of input or sensor the GASMAX II is configured to accept and is typically pre configured at the factory When installed Smart Sensors upload sensor type and other data to the GASMAX and this data may be viewed on the SMART SENSOR information screen NEW SENSOR
15. SHOWN IN THE SECTION ON LOCAL TOXIC SENSORS AND THAT CHANNEL 1 IS TURNED ON IN THE XMITTER CONFIG MENU REMOTE TOXIC SENSOR SETUP GASMAX II units ordered with remote toxic sensors have been pre configured by the factory with the proper settings with regards to sensor zero and span calibration span sensor type and preamp gain If these have been changed please contact GDS Corp for more information NOTE IF AREMOTELY CONNECTED TOXIC SENSOR IS NOT WORKING VERIFY THAT THE REMOTE SENSOR IS CONNECTED AS SHOWN IN THE SECTION ON REMOTE TOXIC SENSORS AND THAT CHANNEL ONE 1 IS TURNED ON IN THE XMITTER CONFIG MENU LOCAL BRIDGE SENSOR SETUP The GASMAX II automatically loads all necessary setup information including the sensor excitation voltage and balance settings from locally connected bridge type sensors via the 10 pin sensor cable No user setup is required NOTE IF ALOCALLY CONNECTED BRIDGE SENSOR IS NOT RECOGNIZED VERIFY THAT THE SENSOR CABLE IS PLUGGED IN AS SHOWN IN THE SECTION ON LOCAL BRIDGE SENSORS AND THAT CHANNEL TWO 2 IS TURNED ON IN THE XMITTER CONFIG MENU REMOTE BRIDGE SENSOR INITIAL SETUP GASMAX gas monitors with remote bridge sensors require one time adjustments to Voltage and Balance to ensure proper operation These adjustments compensate for the unknown length of cable between the Page 30 GASMAX II Operation amp Maintenance Manual Revision 4 0 GASMAX and remote sensor head and any changes to the sensor
16. THIS MENU XMITTER CONFIG 02 TOXIC Enter Key Sequence to access menu HOLD LEL CURRENT ON NEXT KEY Output Zero gt 5 SECONDS NEXT key to Exit Output Span Real Time Clock see Manual HELP Model ST 48 BackLight Figure 9 1 XMITTER CONFIG MENU O2 TOXIC when set to YES enables the Oxygen Toxic channel Channel 1 LEL CURRENT when set to YES enables the LEL Current channel Channel 2 OUTPUT ZERO SPAN TRIM provides a way to precisely set the GASMAX 4mA and 20mA outputs to compensate for variation in output components These settings are programmed at the factory and should not be modified REAL TIME CLOCK adjusts the date and time for use in EVENT LOGGING The current time and date can also be adjusted from the Main Menu See Section 7 MODEL is factory set and should not be modified BACKLIGHT is not available in the GASMAX EC two wire loop powered transmitter Page 50 GASMAX II Operation amp Maintenance Manual Revision 4 0 TECHNICAL PAGE MENU The TECHNICAL PAGE menu is used to adjust certain parameters associated with local or remote sensors To access the TECHNICAL PAGE menu enter the Main Menu move the cursor to the second page and select Technicians Only Enter the key sequence four UP keys to activate the TECHNICAL PAGE menu WARNING TARGET GAS MONITORING AND ALARM PROCESSING ARE NOT ACTIVE WHILE IN THIS MENU MB set Balance Set Sensor Voltag
17. displays the date when a new sensor was last installed RECENT CAL displays the most recent calibration date CLOCK DELAY SETUP PAGE The GASMAX II is equipped with a crystal controlled battery backed real time clock that maintains local Time and Date These values are factory preset to US Central Time and should be reset to correctly match the current time zone during installation to make sure that time stamped Event Log entries are correct CLOCK DELAY SETUP Time 12 35 42 Date 04 22 04 Warm Up Sec 120 Cal Purge Sec 100 Figure 8 7 CLOCK DELAY MENU Page 47 GASMAX II Operation amp Maintenance Manual Revision 4 0 TIME adjusts time of day in hours minutes and seconds DATE adjusts date in month day year WARM UP DELAY sets the amount of time from power on until the 4 20mA output signal begins to track the sensor output Default setting is 60 seconds Maximum value is 255 seconds CAL PURGE DELAY sets the amount of time from the completion of span calibration until the 4 20mA output signal restarts tracking the sensor output The default setting is 60 seconds and the maximum value is 255 seconds LCD CONTRAST ADJUSTMENT PAGE The LCD Contrast Adjustment allows the display to be set for optimum viewing CONT RAST UP DOWN to change NEXT to EXIT Figure 8 8 CONTRAST MENU HELP SCREEN PAGE The Help screen contains several pages of information describing GASMAX operation DI
18. reflections and improves signal noise margin A MODBUS Termination Jumper installs a load resistor across the MODBUS signal lines and should only be set to A ON at the last device in the string Page 16 GASMAX II Operation amp Maintenance Manual Revision 4 0 Cable selection for MODBUS systems is important for both signal integrity and power distribution MODBUS RS 485 transmissions use low voltage differential signaling to achieve reasonable data rates over very long distances up to 4000 feet without a repeater For MODBUS data signals GDS Corp recommends 24GA shielded cable for best results Power distribution however may require larger gauge wire since it is critical that the supply voltage for the GASMAX at the far end of the string not fall below 12VDC during power up and normal operation If the GASMAX includes a GDS IR infrared sensor the voltage must not be allowed to drop below 18V on power up LL o 84 Supply bbon to Display TB1 MODBUS Relay 10 0234 Figure 4 4 MODBUS Wiring Typical Note that while the GASMAX has two sets of wiring terminals for MODBUS A and B signals daisy chain power wiring requires that two wires be installed in the 24 and GND terminals on the GASMAX Power Supply board This be difficult if wire sizes are larger than 18ga Further the addition of multiple MODBUS and power wires inside the GASM
19. store the entire current GASMAX menu database into non volatile memory for restoration later if incorrect values are accidentally entered or uploaded RESTORE CONFIG restores the GASMAX II menu database to the values from the most recent Backup Config This menu item is only available if a smart sensor is not installed The special keystroke sequence of 4 consecutive UP keys is also required to perform backup and restore operations UPLOAD SENSOR DATA allows the user to manually upload the entire smart sensor database to the GASMAX from the smart sensor CAL MARKER allows the user to set the 4 20mA output value that is transmitted during ZERO and SPAN calibration This setting is limited to between 2ma and 20mA and is a useful way to indicate to a GDS controller that the unit is in CAL MODE TX SENSOR LIFE causes the GASMAX 4 20mA output to transmit a sensor life value after the completion of a successful calibration cycle During normal operation the GASMAX transmits a 4mA signal during the CAL PURGE delay to allow time for the span gas to dissipate With TX Sensor Life YES the GASMAX II transmits 4mA for the first 10 seconds then for 5 seconds transmits a value between 4mA and 5mA with 4mA equal to 0 sensor life and 5mA equal to 100 sensor life see Figure 5 5 The output then returns to 4mA for the remainder of the CAL PURGE delay For example if after a calibration sensor life is 75 the GASMAX II transmits 4 75mA duri
20. the cover by hand use a Sensor Head Replacement Tool p n 10 0187 3 Remove the old sensor by pulling straight down NOTE DO NOT TRY TO UNSCREW THE SENSOR PULL STRAIGHT DOWN 4 Carefully install the replacement sensor by aligning the arrow on the sensor with the arrow engraved on the sensor head Push straight up until the sensor connector seats firmly into the sensor connector 5 Reinstall the sensor head cover by CAREFULLY screwing the cover onto the sensor head NOTE IF THE SENSOR FALLS OUT OF THE SOCKET DURING THIS STEP IT CAN BE DAMAGED USE CAUTION WHEN REINSTALLING THE COVER Page 39 GASMAX II Operation amp Maintenance Manual Revision 4 0 11 i 2 REMOVE OLD SENSOR 3 INSTALL NEW SENSOR PULLSTRAI GHT DOWN ALIGN 5 PUSH STRAIGHT UP 1 UNSCREW SENSOR DO NOT ROTATE 4 CAREFULLY REATTACH HEAD COVER SENSOR HEAD COVER Figure 7 1 GASMAX Sensor Replacement Local Smart Sensors are automatically recognized by the GASMAX and the Smart Sensor identification screen shown in Figure 6 1 left side should appear immediately after the installation of a local Smart Sensor If the sensor is the same gas type as was previously installed the sensor s calibration data will be uploaded into the GASMAX II All other parameters stored in the GASMAX II will be retained GASMAX II units can be reconfigured for different sensors by simply installing a different type compatible sensor If a new sensor TYPE is
21. the enclosure provides power management signal output bridge input circuitry Connections for power input and signal output on provided on the left hand side terminal strip and connections for a remote bridge sensor or 4 20 input Channel 2 are provided on the right hand side terminal strip There are four distinct power supply board types The standard 10 0233 I O board has channel 2 input type configured for bridge sensors The 10 0233 420 board has channel 2 configured for 4 20mA input The 10 0233 D4 Sensor Head board has dual 4 20 inputs for both channel 1 and channel 2 The 10 0233 B4 Sensor Head Cover board has channel 1 configured for 4 20mA and channel 2 configured for bridge Sensor Element input These configurations are factory selected during manufacturing and cannot be modified in the field Page 12 GASMAX II Operation amp Maintenance Manual Revision 4 0 SELECTING A LOCATION Factors such as prevailing winds target gas density potential leak sources air movement machinery and similar environmental variables are important when selecting a location for the GASMAX gas monitor or gas sensor Even though the GASMAX II is designed for rugged service sensors and electronics should be protected from environmental damage due to water snow shock vibration and dirt In addition the sensor and or display should be located such that regular maintenance and periodic sens
22. to two remote sensors 13 GASMAX II Operation amp Maintenance Manual Revision 4 0 Figure 4 1 GASMAX Remote Sensor EXPLOSION PROOF INSTALLATION GASMAX II monitors with standard explosion proof sensor heads are certified for use in Class 1 Division 1 hazardous areas Installation in these areas should follow best industry standard practices and all appropriate electrical codes Generally these codes require rigid metal conduit poured seals and other installation elements necessary to ensure safety In all cases GDS Corp recommends any GASMAX sensor be mounted vertically with the sensor opening facing down If there is a possibility that water or other liquid may be present GDS Corp further recommends the installation of a sensor head Splash Guard p n 10 0205 to protect the sensor from damage For maximum protection against RF interference or electrical surge the GASMAX II enclosure all remote sensors and interconnecting conduit must be properly grounded INTRINSICALLY SAFE INSTALLATION The GASMAX II is not certified for use as an Intrinsically Safe device Page 14 GASMAX II Operation amp Maintenance Manual Revision 4 0 CONNECTING DC POWER amp OUTPUT SIGNAL WIRING To access the GASMAX signal and power connections remove the cover on the GASMAX II explosion proof enclosure loosen the 2 thumbscrews holding the display assembly and remove it The display will remain connected to the Su
23. 0 7 ma __ fats fener roam 9 6 8 0 1 __ fats 9 9 0 9 lt 3 Renee TRANSMITTER STATUS WORD BIT DEFINITION i eo eeens ewer md Fae 9 normaly 6 lt 9 0000 CHANNEL FLOATING POINT DEFINITION Channel Floating Point 15 bit plus sign 2 s complement with 5 over under range applied Contact GDS Corp for more information Page 58 GASMAX II Operation amp Maintenance Manual Revision 4 0 TOXIC SENSOR INDICATES FAULT OR OVERRANGE Certain toxic sensors indicate off scale low or high at power up and quickly drift towards zero This is normal behavior Toxic sensors showing constant FAULT If local remove sensor and examine for moisture or discoloration Replace sensor if wet or discolored If remote check sensor cable and junction box for moisture or standing water Remove sensor and examine for moistu
24. 137 mm Height 8 203 mm Depth 5 127 mm Shipping weight 6 5 pounds 3 kg Approvals CSA Certified Division 1 amp 2 Groups B C D Suitable for explosion proof installations with flame arrestor Warranty Two years on electronics one year on sensor Page 62 GASMAX II Operation amp Maintenance Manual Revision 4 0 DISPLAY AND ENCLOSURE I O Power Supply Ch1 Ch2 10 0233 Toxic Bridge 10 0233 420 Toxic 4 20mA 10 0233 B4 4 20mA Bridge 10 0233 04 4 20mA 4 20mA z LEL 01 HABE Yellow Enclosure 10 0160 GASMAX Enclosure Sensor Head Assembly 10 0247 Toxic or Bridge Direct Type 1 2 10 0247F Toxic Direct Reactive Gas Type 3 4 10 0248 Toxic Sensor Transmitter Type 20 21 10 0248F S T Reactive Gas Type 22 23 Note Does not include sensor Display 10 0232 GASMAX Display Figure 13 1 GASMAX II Local Sensor Spare Parts Sensor Head Assembly See list above Sensor Head Base lt Sensor 10 95xx Toxic combustible SmartIR PID Sensor Head Cover Figure 13 2 GASMAX Sensor Head Page 63 GASMAX II Operation amp Maintenance Manual Revision 4 0 EXPANSION BOARDS O MODBUS Relay Board K1 Isolated Dual 4 20mA Output i 2 n 10 0234 MODBUS Relays 3 LEL Out 2000 0135 MODBUS only K2 40 ig ovt ISOLATED 4 20mA Board
25. 3 4 Sensor head with extended 12 cable Figure 13 7 GASMAX II Dual with Y Adapter Page 66 GASMAX II Operation amp Maintenance Manual Revision 4 0 NPT 3x Universal Sensor Head Single Sensor Configuration shown with optional 10 0247 smart sensor head Figure 14 1 GASMAX Dimensions NPT 2x Dual Sensor 12 5 Configuration shown with optional Sansar Head 10 0247 smart Fitting Adapter sensor heads NEN Figure 14 2 GASMAX Dual Local Sensor Dimensions Page 67
26. A2 IN END OF LOG Clear Event Log 08 12 04 03 55 ACK Down 08 12 04 04 16 2 08 12 04 04 23 08 12 04 15 00 A1 IN 08 12 04 16 43 10 08 13 04 02 08 IN Figure 8 4 ALARM SETTINGS MENU SET POINT enters the engineering unit value where the alarm trips It may be negative and trip when monitored values fall out of range in this direction A3 has a default setting of negative 10 with Low Trip set for YES This makes it function as a FAULT alarm and trip when the monitored value falls below 10 It is important to adjust this value when the transmitter s span value is set for another value other than 100 For example a typical span setting for monitoring oxygen level is 0 25 0 96 therefore the fault level value should be adjusted to 2 5 which is equivalent to negative 1096 of full scale DEAD BAND has a minimum value of 196 and a maximum value of 1096 It is useful for preventing alarm cycling when the monitored value is hovering around the set point Page 45 GASMAX II Operation amp Maintenance Manual Revision 4 0 EXAMPLE With a range of 0 100 ppm if Dead Band equals 5 and the set point is 20 ppm after tripping at 20 ppm the value must drop below 15 ppm to reset ON DELAY allows entering a maximum 10 second delay before this alarm becomes active This is useful for preventing nuisance alarms caused by brief spikes beyond the set point OFF DELAY allows entering a maxim
27. AGNOSTICS PAGE The Diagnostics page provides tools for use during setup or testing Since relays are not available on the II the Relay Test option is not functional WARNING DIAGNOSTICS m OUTPUT STIMULATOR 4 Alarm processing will EDIT Output Stimulation Out put 4 0 mA be halted during Relay Test diagnostic mode EDIT to change Next to exit EDIT to continue Any other key to exit m ACTIVATE RELAYS Ea Relay 1 OFF Relay 2 OFF Relay 3 OFF Figure 8 9 DIAGNOSTICS MENU OUTPUT SIMULATION allows setting the 4 20mA output to virtually any desired value This is useful for checking responses of devices receiving the GASMAX II s 4 20mA output Page 48 GASMAX II Operation amp Maintenance Manual Revision 4 0 RELAY TEST allows the user to manually activate any of alarm relays independent of the presence of gas This is useful during troubleshooting or initial installation when an end to end test of relay functionality must be done WARNING TARGET GAS MONITORING AND ALARM PROCESSING ARE NOT ACTIVE WHILE IN THIS MENU SYSTEM SECURITY PAGE The System Security menu offers two levels of protection against operation by unauthorized personnel or those with malicious intent SYSTEM SECURITY B Contact Name Secure Level LOW Pass Code Unlocked Figure 8 10 SYSTEM SECURITY MENU CONTACT NAME
28. AX enclosure can create problems and possibly damage components if the display has to be forced into place Finally if it is desired to disconnect the GASMAX from the MODBUS loop for troubleshooting disconnecting the power wire removes power from all devices further down the loop and leaves a live male pin with 24V inside the enclosure Page 17 GASMAX II Operation amp Maintenance Manual Revision 4 0 For these reasons GDS Corp recommends the addition of the MODBUS Wiring Junction Box see Fig 4 7 This option minimizes the need to access wiring inside the GASMAX II provides individual wire landing points for incoming and outgoing MODBUS and power wiring and shields and makes it easy to temporarily disconnect the GASMAX Il power or MODBUS connections without affecting any other MODBUS devices Figure 4 5 MODBUS Wiring MODBUS Junction Box The MODBUS wiring junction box is attached to the GASMAX either on the bottom fitting or one of the side fittings depending on installation requirements Specify BOTTOM LSIDE or RSIDE when ordering See Fig 4 8 MODBUS MODBUS IN Figure 4 6 MODBUS JBOX LOCATION OPTIONS Page 18 GASMAX II Operation amp Maintenance Manual Revision 4 0 OPTIONAL DUAL ISOLATED 4 20MA OUTPUT BOARD The optional 10 0250 Dual Isolated 4 20mA output board provides two dual 4 20mA outputs that are electrically isolated from sensor inputs and the 24 VDC power source Each 4 20mA outp
29. Cal Fails If SPAN Cal OK show for 5 seconds REPEAT CAL REPEAT CAL SPAH CAL ZERO CAL SPAN FAIL Successful ERROR CODE 4 successful ERROR CODE 5 lt Figure 6 1 Calibration Flowchart Page 38 GASMAX II Operation amp Maintenance Manual Revision 4 0 NORMAL MAINTENANCE Normal maintenance for the GASMAX II primarily involves periodic calibration on standard intervals GDS Corp recommends calibration at least every three months or more often if temperature extremes vibration the presence of incompatible gases or other environmental factors may accelerate the deterioration of the sensor element Calibration should also include inspections for clogged or wet sensor heads cracked or damaged enclosures and water incursion inside conduit or junction boxes SENSOR REPLACEMENT LOCAL SENSORS If a sensor shows FAULT does not respond to gas or can no longer be calibrated it should be replaced GASMAX II monitors use GDS Corp type 10 95XX toxic or combustible sensors where the XX is the gas type or GDS IR infrared sensors For toxic or combustible sensors the range value should also be specified when ordering replacement sensors For example a replacement H2S sensor for 0 100 ppm would be 10 9515 0100 To replace a GASMAX local sensor 1 Declassify the area or remove power to GASMAX II 2 Unscrew the sensor head cover If unable to open
30. FROM GDS CORP Page 25 GASMAX II Operation amp Maintenance Manual Revision 4 0 LOCAL GDS IR INFRARED SENSOR CH 2 When the GASMAX II is configured to include a GDS IR Infrared Combustible CO2 sensor the IO Power Supply board is factory modified to make Channel 2 compatible with the sensor s 4 20mA input signal An integrated zero set pushbutton and magnetic zero switch is included inside the GASMAX II enclosure and is used to periodically set the zero point for the GDS IR Zero set pushbutton located inside GASMAX enclosure 10 Power Supply 10 0233 420 Ribbon to Display I O Power Supply with 4 20mA In Factory Supplied Wiring IR ZERO RED 4 20 581 W E i k 55 o 10 SECONDS 2008 0268 02 N CLEAR AIR SENSOR ue Rei GDS IR Red Wire to TB1 RED GDS IR Blue Wire signal to TB1 BLU GDS CORP ZERD IR GDS IR White Wire zero to TB1 WHT GDS IR Black Wire to TB1 BLK Figure 4 13 GASMAX with Local GDS IR Page 26 GASMAX Operation amp Maintenance Manual Revision 4 0 CONNECTING A REMOTE GDS IR INFRARED SENSOR CH 2 GASMAX II monitors with remote mount GDS IR sensors are shipped in two pieces and sensor wiring must be installed by the end user GDS IR sensors can be mounted up to 500 feet from the GASMAX display Cable used should be
31. MEN DNA e 48 51025 5555 49 FIGURE 9 1 XMITTER 9 6 7 2 0 0 50 FIGURE 9 2 TECHNICAL PAGE MENU 51 FIGURE 9 3 SENSOR BALANCE amp VOLTAGE SET MENU 1 52 FIGURE GAIN TO UNITY MEN saisit 52 FIGURE 9 5 1 SETVE 53 FIGURE 15 1 GASMAX EOCAE SENSOR SPARE 63 15 2 25 ihre 63 FIGURE 13 3 GASMAX EXPANSION BOARDS 2 via Beca ausis 64 FIGURE 13 4 GASMAX SENSOR HEAD SPLASH GUARD amp FLOW 64 13 5 GASMAX I REMOTE DIRECT SENSOR HEAD si tin tee caen Rene 65 FIGURE 13 6 GASMAX REMOTE SENSOR
32. MODBUS slave devices with identical MODBUS address GASMAX DISPLAY BLANK Verify DC power at 0 Supply board TB2 terminals 1 24 and 4 Gnd Verify ribbon cable connected between IO Power Supply board and Display Assembly Verify that there are no wires connected to the 4 20mA LOOP INPUT on the back of the Display Assembly GASMAX ERROR CODES 01 Incorrect sensor type new sensor does not match most recent type of sensor This is normal if changing sensor types If unexpected verify that new sensor type matches previous sensor type 02 Zero or span mismatch Smart sensor zero or span values differ from those stored in the GASMAX 03 Sensor Calibration Error Contact factory Page 60 GASMAX II Operation amp Maintenance Manual Revision 4 0 04 Zero calibration failure Zero readings must be within 10 of zero For example if the range is 0 100 ppm the zero reading cannot be above 10 ppm For bridge type sensors it may be possible to readjust the balance to restore a zero reading Toxic sensors with high zero readings must be replaced 9 05 calibration failure readings must be within a range of from to 2x the target value For example if the target is 50 ppm the sensor must output at least 25 ppm and no higher than 100 ppm at the current preamp gain setting for calibration to proceed 06 History data file full Clear event log to remove 9 07
33. R IS NOT SUPPLIED WITHIN 3 MONTHS OF SHIPMENT FROM GDS CORP Page 11 GASMAX II Operation amp Maintenance Manual Revision 4 0 The GASMAX II consists of a display assembly with optional MODBUS alarm relay interface I O power supply board sensor head body sensor head cover and sensor The display assembly contains the microprocessor LCD display magnetic switches alarm indication LEDs and toxic sensor interface electronics Channel 1 The display connects to the I O power supply board via a short ribbon cable This cable should remain connected at all times If a local toxic sensor is connected to the GASMAX II it Display Front connects to the S1 connector on the back of the display If the GASMAX II is equipped with the optional MODBUS relay interface board this board is mounted to the back of the display using three extended length 4 40 screws The GASMAX software automatically recognizes the presence of the MODBUS relay interface board if installed Optional MODBUS relays Mounts on display back The display and optional MODBUS relay interface board are attached to the power supply board using standoffs and thumbscrews To access the I O power supply board power supply board loosen the thumbscrews and allow the display to hang by the ribbon cable This can be done without removing power to the unit The I O power supply board is mounted on the back side of
34. TS set the resolution of the LCD readings and may be set for 0 1 or 2 For example ZERO readings for 0 1 amp 2 decimal points displays as 0 0 0 amp 0 00 CAL SPAN VALUE sets the engineering units value of the calibration gas GDS Corp recommends that the calibration gas value be between 25 and 7596 of full scale Calibrating at 10096 of scale is not recommended READOUT DEADBAND forces low values to continue to read zero This is useful when there are small amounts of background gases that may cause fluctuating readouts The highest amount of deadband allowed is 596 NOTE THE 4 20MA OUTPUT IS NOT AFFECTED BY THIS SETTING TRACK NEGATIVE allows the display to show negative values when set to YES This can be helpful when troubleshooting sensor problems The default setting is NO and forces the display to read O if Page 43 GASMAX II Operation amp Maintenance Manual Revision 4 0 the sensor value drops below zero However negative sensor outputs will always cause the Fault alarm to trip 4 20mA output always locks at 4mA when the reading drifts negative TEMP COMPENSATION adjusts sensor output based on ambient temperature GDS Corp temperature compensated sensors are preprogrammed with the necessary table of values and are automatically uploaded to the GASMAX II from the smart sensor This menu item is not accessible unless a temperature compensated local Smart Sensor is installed BACKUP CONFIG allows users to
35. age to match the needs of the sensor Page 51 GASMAX II Operation amp Maintenance Manual Revision 4 0 Remote sensors require manual adjustment Excitation voltage must be measured at the sensor therefore if the sensor is mounted some distance away from the GASMAX II the excitation voltage may have to be higher to compensate for losses in field wiring WARNING EXCEEDING A SENSOR S RATED EXCITATION VOLTAGE MAY DAMAGE OR DESTROY THE SENSOR SENSOR BALANCE amp SENSOR VOLTAGE menus are only active when input type Cat Bead 3 Wire SEHS R BHLHHCE Reading Counts SS SEHS R WOLTAGE Volts 2 04 to Change HEST to Exit 5 High voltage damage sensor to Change HEAT to Exit Figure 9 3 Sensor Balance amp Voltage Set Menu SET GAIN TO UNITY clears any previous calibration OFFSET and GAIN values to 0 0 and 1 0 respectively This item is useful if a previous calibration was done in error or if screen readings appear incorrect for no apparent reason WARNING A FULL CALIBRATION SHOULD ALWAYS BE PERFORMED AFTER A SET UNITY COMMAND kkk C WARNING Previous Calibration will be erased EDIT Gain Unity EDIT to confirm NEXT to exit Figure 9 4 SET GAIN TO UNITY MENU PREAMP GAIN SET allows adjustment of the analog amplifiers that match the sensor output to the optimum inp
36. ational NORMAL OPERATION During normal operation the GASMAX display shows the current gas reading in direct calibrated engineering units If the reading goes above the Alarm 1 or Alarm 2 values the front panel display LEDs will flash and the internal relays if installed and programmed properly will activate The 4 20mA outputs will transmit values that represent the 96 of scale shown on the display If the sensor malfunctions or is removed the Fault LED will illuminate and the message FAULT will appear on the display screen The GASMAX II display is shown in Figure 2 1 There are four magnetic switches on the face of the GASMAX II arranged in a quadrant around the LCD display Starting in the upper right and proceeding clockwise these are labeled NEXT EDIT DOWN CAL and UP To activate or press a magnetic switch swipe the magnet near the switch Zz LEL REASUREMRENT NARE Figure 5 5 1 GASMAX II DATA DUAL CHANNEL and TREND DISPLAY Pressing the NEXT key causes the GASMAX display to switch display screens In single channel mode the display will switch between DATA and TREND In dual channel mode the sequence will be DATA 1 DATA 2 TREND 1 TREND 2 DUAL CHANNEL followed by DATA 1 Page 32 GASMAX II Operation amp Maintenance Manual Revision 4 0 The EDIT key activates the USER MENU display mode When in user menu display mode use UP and DOWN to select an item EDIT to change an item and NEXT to exit the menu or
37. bration to be successful To adjust the balance access the Technician s Menu see Section 8 2 Select Set Balance and use the Up and DOWN keys to bring the reading close to zero NOTE BRIDGE SENSORS DRIFT DURING WARMUP AND REQUIRE TIME TO STABILIZE See Table NOTE ALWAYS VERIFY SENSOR VOLTAGE BEFORE ADJUSTING BALANCE NOTE MAKE SURE NO TARGET GAS IS PRESENT WHEN ADJUSTING BALANCE Once operational the user should verify the following settings prior to initial calibration 1 Localtime and date Check date value and adjust time for proper time zone Sec 7 5 2 Tagname or Engineering Units settings Edit values as necessary Sec 7 2 3 CALSPAN GAS value Set to match concentration of calibration gas cylinder Sec 7 2 4 CALMARKER value Adjust desired output mA during calibration Sec 7 2 Page 31 GASMAX II Operation amp Maintenance Manual Revision 4 0 5 ALARM 1 ALARM 2 settings Set for desired levels NOTE If relays are not installed GASMAX II programmable alarm levels affect operation of front panel LEDs only Sec 7 3 Allow the GASMAX II to stabilize for at least four hours preferably overnight if possible This will allow all sensors to reach stable equilibrium with respect to environmental conditions such as ambient temperature humidity and barometric pressure as well as applied reference and counter voltages generated by the GASMAX II electronics At this point the GASMAX can be calibrated and made oper
38. c Sensor CH1 20 Connecting a Remote Toxic Sensor CH1 21 Connecting a Remote Toxic Sensor TRANSMITTER CH1 22 Local Combustible Sensor CH2 23 Connecting a Remote Combustible Sensor Ch 2 24 Connecting a Remote TOXIC Sensor TRANSMITTER Ch 2 25 Local GDS IR Infrared Sensor Ch 2 26 Connecting a Remote GDS IR Infrared Sensor Ch 2 27 Page 3 GASMAX II Operation amp Maintenance Manual Revision 4 0 Connecting an External 4 20mA Input Device Ch 2 GASMAX Dual 4 20mA or 4 20MA Bridge Input Option 5 INITIAL SETUP AND OPERATION Local Toxic Sensor Setup Remote Toxic Sensor Setup Local Bridge Sensor Setup Remote Bridge Sensor Initial Setup Initial Bridge Sensor Volts Check Initial Bridge Sensor Balance Check Normal OperatlON Display Screens Alarm Operation ALARM 1 and 2 Alarm Operation ALARM 3 6 CALIBRATION Calibration Overview Calibration Procedure 7 MAINTENANCE Normal Maintenance Sensor Replacement Local Sensors Sensor Replacement Remote Sensors 8 USER MENUS Main Menu System Configuration Page Measurement Name Eunits Page 4 28 29 30 30 30 30 30 31 31 32 33 35 35 36 36 37 39 39 39 41 42 42 43 43 43 GASMAX II Operation amp Maintenance Manual Revision 4 0 Zero 0 Span 100 Decimal Points Cal Span Value Readout Deadband Track Negative Temp Compensation Backup Config Restore Config Upload Sensor Data Cal Mar
39. d should be three wire stranded with foil shield and should be run inside metallic rigid conduit where possible GDS Corp recommends Belden B8771 The cable shield must be connected to an earth ground at ONE END ONLY Remote bridge sensors connect to TB1 on the 10 Power Supply board located on the back of the explosion proof enclosure See Fig 4 8 WARNING REMOTE BRIDGE SENSORS DO NOT AUTOMATICALLY ADJUST SENSOR EXCITATION VOLTAGE IF SWITCHING SENSOR TYPES BE SURE TO ADJUST SENSOR VOLTAGE BEFORE INSTALLING A NEW SENSOR 10 0233 I O Power Supply with Bridge Input GMII TB1 REF to J box R GMII TB1 COM to J box C GMII TB1 ACT to J box A Figure 4 11 Remote Bridge Sensor Connection Page 24 GASMAX II Operation amp Maintenance Manual Revision 4 0 CONNECTING A REMOTE TOXIC SENSOR TRANSMITTER CH 2 GASMAX II monitors with remote mount toxic sensor transmitters are shipped in two pieces and sensor wiring must be installed by the end user When used with Channel 2 toxic sensor transmitters connect to the Channel Two 4 20 input on the right hand side terminal strip of the I O power supply board The 10 0233 4201 power supply board must be configured for 4 20mA input as shown below IO Power Supply 4 20mA OUT 20m SENSOR Figure 4 12 Remote Sensor Transmitter Connection IMPORTANT TOXIC SENSORS ARE SUBJECT TO ACCELERATED DETERIORATION IF POWER IS NOT SUPPLIED WITHIN 3 MONTHS OF SHIPMENT
40. e Set Gain to UNITY Reading 3 Counts 496 PreAmp Gain Set Input Type ZERO Cal Val 0 V VV UP DN to Change NEXT to Exit TECHNICAL PAGE 1 EUH SENSOR BALANCE SENSOR BALANCE amp SENSOR VOLTAGE menus are only active when input type Cat Bead 3 Wire TECHNICAL PAGE 2 SENSOR VOLTAGE Raw Min Onts 511 Volts 2 04 Raw Max Cnts 1000 UP DN to Change NEXT to Exit WARNING High voltage may damage sensor k k WARNING Previous Calibration will be erased EDIT Gain Unit EDIT to confirm NEXT to exit PGA SETUP Gain 25 0 Counts 10 11 Reading 100 Up Dn to Change Next to exit SELECT INPUT SELECT EUNITS Cat Bead 3 Wire EDIT gt gt Custom UP DOWN to change EDIT to select NEXT to exit Figure 9 2 TECHNICAL PAGE MENU SET BALANCE adjusts the balance of a bridge type sensor and must only be performed with ZERO gas on the sensor Balance is similar to a very coarse ZERO calibration and does not need to be precise since subsequent calibrations will correct for small errors ZERO gas applied to the sensor should provide a Reading of 3 to 3 on the SENSOR BALANCE menu SET VOLTAGE adjusts the excitation voltage applied to bridge type sensors and may vary from 2 to 6 volts Local Smart Sensors automatically adjust the excitation volt
41. e Sensor Indicates Fault or Overrange Bridge Sensor Will Not Calibrate Receiving Device and GASMAX Displayed Values Don t Match Controller MODBUS Data Incorrect Controller Showing MODBUS COMM ERROR GASMAX Display Blank GASMAX Error Codes Software reset Cold Boot 12 SPECIFICATIONS 13 SPARE PARTS Display and Enclosure Expansion Boards Sensor Head Accessories Remote TOXIC OR BRIDGE Sensor Remote TOXIC Sensor Transmitter Dual Local Sensors 14 Drawings and Dimensions Page 7 58 59 59 59 59 59 59 60 60 60 60 61 62 63 63 64 64 65 65 66 67 GASMAX II Operation amp Maintenance Manual Revision 4 0 TABLE OF FIGURES FIGURE 4 1 GASIVIAX REMOTE SENSOR Ue 14 FIGURE 4 2 GASMAX POWER amp SIGNAL WIRING eene enne nnne nnn 15 FIGURE 4 3 OPTIONAL RELAY MODBUS INTERFACE 16 FIGURE 4 4 MODBUS WIRING TYPICAL acti oes esa uteri gea ovo eue ava a oed veris apa 17 FIGURE 4 5 MODBUS WIRING MODBUS JUNCTION nennen nennen 18 FIGURE 4 6 MIODBUSJBOX LOCATION OPTIONS ad 18 FIGURE 4 7 OPTIONAL DUAL ISOLATED 4 20MA QU TPUT sia 19 FIGURE 4 8 LOCAL SMART TOXIC SENSOR CONNECTION eese 20 FIGURE 4 9 REMOTE
42. four wire stranded with foil shield The cable shield must be connected to an earth ground at ONE END ONLY In this configuration a zero set pushbutton is located in the GDS IR remote mount junction box and a zero set pushbutton and zero set magnetic switch are located in the GASMAX display GASMAX II Display Remote GDS IR Sensor A OUT BLUE COMMON lt BLK a a ZERO User Supplied Wiring 10 Power Supply COS Four conductors Factory Supplied Wiring 1 IR ZERO RED m PWR 4 20 COM I RED 18 to 30VDC Power to GDS IR O PRESS FOR O 10 SECONDS 2 BLUE 4 20mA analog out from GDS IR P N 2 8 0268 82 IN CLEAR AIR Le WHITE Zero input to GDS IR GDS IR Interface Board p m BLACK Common ground Mounted inside GASMAX Figure 4 14 Remote GDS IR Connection Page 27 GASMAX II Operation amp Maintenance Manual Revision 4 0 CONNECTING AN EXTERNAL 4 20MA INPUT DEVICE CH 2 GASMAX II can be factory configured to support a general purpose non isolated 4 20mA input channel 2 Power Supply boards that have been converted to 4 20mA will have TB1 marked to indicate PWR 24V 4 20 IN signal and COM ground The amount of voltage and current available for the remote 4 20mA device is determined by the GASMAX DC supply connected to TB2 Note that in this case channel 1 is sti
43. function and return the GASMAX II to display mode Activating DOWN CAL followed by EDIT while in display mode initiates calibration mode For the balance of this manual the term press will be used to describe activation of any key via the magnetic wand DISPLAY SCREENS The DATA display screen shows a single channel s information The current value is shown in calibrated engineering units A horizontal bargraph tracks the current value and shows the Alarm 1 and Alarm 2 values in graphical form The user programmable Engineering Units Eunits and Measurement Name text strings are shown below the real time reading Above the LCD display three LEDs indicate the status of the level and fault alarms If relays are installed the LEDs indicate whether the relays are active Note that if any relay is set for FAILSAFE operation if LED is ON the relay will be de energized In dual channel mode if either channel is in alarm the corresponding A1 or A2 indicator LED and relay will be energized Z LEL MEASUREMENT Figure 5 5 2 GASMAX Data Display To the right of the LCD display two LEDs monitor the MODBUS RS 485 transmit TXD and receive RXD buffers Flashing indicates sent or received data In normal operation RXD will flash whenever a message from the MODBUS master is received and TXD will flash when any response message is transmitted from the GASMAX These only operate if a MODBUS interface is installed Page 33
44. idge 4 20ma input I O power supply board is installed in the GASMAX then the remote sensor transmitter is connected as shown below 24 is not available on TB1 pin 1 IMPORTANT TOXIC SENSORS ARE SUBJECT TO ACCELERATED DETERIORATION IF POWER IS NOT SUPPLIED WITHIN 3 MONTHS OF SHIPMENT FROM GDS CORP Page 22 GASMAX Operation amp Maintenance Manual Revision 4 0 LOCAL COMBUSTIBLE SENSOR CH2 Local bridge type sensors including catalytic bead or infrared sensors for combustibles and photoionization detectors PID for volatile organic compounds are factory installed and always connected to the Channel 2 Smart Sensor connector 51 on the Supply board located on the back of the explosion proof enclosure See Fig 4 7 NOTE LOCAL SMART BRIDGE SENSORS AUTOMATICALLY ADJUST SENSOR EXCITATION VOLTAGE CL JC Bridge Sensor 10 0233 I O Power Supply with Bridge Input Local Bridge Sensor Cable from sensor head connects to S1 on IO Power Supply assembly Figure 4 10 Local Smart Bridge Sensor Connection Page 23 GASMAX II Operation amp Maintenance Manual Revision 4 0 CONNECTING A REMOTE COMBUSTIBLE SENSOR CH 2 GASMAX II monitors with remote mount bridge type sensors are shipped in two pieces and sensor wiring must be installed by the end user Bridge type sensors have a more robust output and can be mounted up to 100 feet from the GASMAX II Cable use
45. installed the Smart Sensor identification screen will appear followed by the ERROR CODE 01 message and the user will be given the opportunity to confirm the new sensor type If the user activates the EDIT key all data stored in the new sensor s database including range tag name cal span value engineering units and alarm levels will replace the current settings SMART SENSOR ERROR CODE 01 Type Cat Bead Incorrect Sensor pan 100 installed Install If installed sensor Zero 0 correct sensor or t d t tch SN XXXXXX update transmitter ype oes no 01 28 04 SEE MANUAL transmitter database Last Cal 04 05 04 EDIT key to update ANY key to Exit Any other to abort Figure 7 2 SMART SENSOR Recognition Screen Page 40 GASMAX II Operation amp Maintenance Manual Revision 4 0 SENSOR REPLACEMENT REMOTE SENSORS To replace a GASMAX remote sensor 1 2 Declassify the area or remove power to the GASMAX II Unscrew the sensor head cover If unable to open the cover by hand use a Sensor Head Replacement Tool p n 10 0187 Remove the old sensor by pulling straight down NOTE DO NOT TRY TO UNSCREW THE SENSOR PULL STRAIGHT DOWN Carefully install the replacement sensor by aligning the arrow on the sensor with the arrow engraved on the sensor head Push straight up until the sensor connector seats firmly into the sensor connector Reinstall the se
46. isa 12 character ASCII field available for displaying a phone or name of personal who knows the Pass Code Lost Pass Codes may be recovered by entering the locked security menu and holding the UP key for 5 seconds The 4 digit code appears near the bottom of the screen SECURE LEVEL sets LOW HIGH or OFF modes A LOW level allows CAL MODE sensor calibrations but requires the 4 digit Pass Code prior to altering menus HIGH level locks the entire menu database and the CAL Mode until the correct Pass Code is entered LOW and HIGH security levels always allow static viewing of configuration menus Page 49 GASMAX II Operation amp Maintenance Manual Revision 4 0 The TECHNICIANS MENU group consists of the XMITTER CONFIG menu and TECHNICAL PAGE menu These menus contain items that are typically factory configured depending upon the type sensor and input connected Care should be used when modifying these variables as some items will prevent proper operation and could endanger personnel Access requires a special key sequence of four UP keystrokes to prevent accidental modification of critical items XMITTER CONFIG MENU XMITTER CONFIG menu is used to activate channels precisely calibrate 4 20 outputs and set time date To access the XMITTER CONFIG menu press and hold the NEXT key for 5 seconds until the screen appears requesting the special key sequence WARNING TARGET GAS MONITORING AND ALARM PROCESSING ARE NOT ACTIVE WHILE IN
47. k Negative 5 BE ME o Sensor Information Zero m Eunits Linearization Data gt ONU Data Point 1 ClockzDelass Span 905 Backur Config gt HERT to Exit Input 18 88 Diagnostics Decimal Points a Restore UrFload utrut 18 88 HELF Instructions Cal Span Ual 5a Cal Marker 5 88mA see Manual HELP y y TH Sensor Life Simple Sensor Installed Smart Sensor Installed LEL INPUT 2 m ALARM SETTINGS ALARM x SETUP 7j BW LCD Contrast Adi i c 2 dene ES BP Alarm 1 B Set Point 28 are identical Modbus 5485 Port oe I ped Bie UTE Alarm 3 Fail gt ON Delas Bs iln 2 Relay Config OFF Delay Bn mart sensor only pm Firmware Rev Catching 2 EVENT 108 08 12 04 2 7 AL IM 266 ear Event Log lee 88 12 04 84 16 AZOUT 25485 MODBUS SETUP RELAY CONFIG 34 ane Address 8812 84 16 45 ALOUT 7 fate 22 Failsafe 057137604 2 05 AZ IH Parity Hone k2 Acknowledge Stor Bit 1 Refresh oft Down KS always Failsafe 515704 8278 INSTALL SENSOR menu not rm available with Smart sensor installed END OF LOG SENSOR SETUPINFO INSTALL SENSOR INSTALL SENSOR Inetali 5enzer EDIT to install Historical CAL data Recall Cal History 2 Hew Sensor EDIT Will be Deleted Input Tyre Cat
48. ker TX Sensor Life Alarm Settings Page Set Point Dead Band ON Delay OFF Delay Low Trip Latching Display Event Log Clear Event Log RS 485 Communications Sensor Setup Install New Sensor Recall Cal History Input Type New Sensor Recent Cal Clock Delay Setup Page Time Date Warm Up Delay Cal Purge Delay LCD Contrast Adjustment Page Page 5 43 43 43 43 43 43 44 44 44 44 44 44 45 45 45 46 46 46 46 46 46 46 46 47 47 47 47 47 47 48 48 48 48 48 GASMAX II Operation amp Maintenance Manual Revision 4 0 HELP Screen Page 48 Diagnostics Page 48 Output Simulation 48 Relay Test 49 System Security Page 49 Contact Name 49 Secure Level 49 9 TECHNICIANS MENUS 50 XMITTER CONFIG Menu 50 2 Toxic 50 LEL Current 50 Output Zero Span Trim 50 Real Time Clock 50 Model 50 TECHNICAL PAGE Menu 51 Set Balance 51 Set Voltage 51 Set Gain to Unity 52 Preamp Gain Set 52 Zero Cal Value 53 Raw Min Max Counts 53 Marker Active 53 Marker TX LED 54 Mark Level 54 Mark As Message 54 10 MODBUS REGISTERS 55 List of GASMAX II MODBUS variables 55 Channel Status Word Bit Definition 57 Alarm Status Word Bit Definition 58 Transmitter Status Word Bit Definition 58 Page 6 GASMAX II Operation amp Maintenance Manual Revision 4 0 Channel Floating Point Definition 11 TROUBLESHOOTING GUIDELINES Toxic Sensor Indicates Fault or Overrange Toxic Sensor Will Not Calibrate Bridg
49. ll available to support a local or remote toxic sensor The calibrated output for channel 2 is available on TB2 Pin 3 WARNING 10 POWER SUPPLY BOARDS THAT HAVE BEEN CONVERTED TO 4 20MA WILL NOT SUPPORT LOCAL OR REMOTE BRIDGE TYPE SENSORS ATTACHING A BRIDGE TYPE SENSOR WILL DAMAGE OR DESTROY THE SENSOR 10 0233 420 Power Supply with 4 20mA In 182 1 24VDC Input TB2 2 TB2 3 Channel 2 4 20mA Out TB2 4 Power Signal Common Figure 4 15 Remote 4 20mA Input Ch 2 Page 28 PWR gt 24VDC from TB2 1 420 IN gt Channel 2 Analog Input COM Common from TB2 4 GASMAX II Operation amp Maintenance Manual Revision 4 0 GASMAX DUAL 4 20MA OR 4 20MA BRIDGE INPUT OPTION GASMAX II can be factory configured to support two general purpose non isolated 4 20mA inputs on channels 1 and 2 10 0233 D4 or one non isolated 4 20mA input on Channel 1 and one bridge style input on Channel 2 10 0233 B4 Power Supply boards designed for dual 4 20mA inputs will have TB1 marked to indicate PWR 24V 4 20 IN 2 signal COM ground and 4 20 IN 2 signal The amount of voltage and current available for the remote 4 20mA device is determined by the GASMAX DC supply connected to TB2 WARNING DO NOT CONNECT A BRIDGE STYLE SENSOR TO TB1 IF THE INPUT HAS BEEN CONFIGURED FOR 4 20MA THE 24V EXCITATION VOLTAGE WILL DESTROY THE BRIDGE STYLE SENSOR The most common usage for dual 4 20 inputs is for
50. ng the 5 second interval NOTE TX SENSOR LIFE SHOULD ALWAYS BE SET FOR NO UNLESS THE 4 20MA RECEIVER IS CAPABLE OF INTERPRETING THE SENSOR LIFE SIGNAL MOST GDS CORP PROTECTOR SERIES CONTROLLERS INCLUDE THIS CAPABILITY Page 44 GASMAX II Operation amp Maintenance Manual Revision 4 0 4mA for 10 seconds after Cal Exit Then 4 5mA for 5 seconds Sensor Life Value 4mA 0 life 5mA 100 life Monitoring Monitoring Cal Marker Adjustable Calibrating Cal Delay Figure 8 3 SENSOR LIFE TRANSMISSSION FORMAT ALARM SETTINGS PAGE The Alarm Settings page covers the Alarm 1 2 3 Setup and Event Log menu items Alarm 1 Alarm 2 and Alarm 3 Fail menus are identical and are therefore described only once If the optional alarm relays are not installed the alarm settings only affect the operation of the front panel LEDs In that case separate alarm settings may need to be programmed in the 4 20mA receiving device Alarm 1 2 3 menus are identical ALARM SETTINGS ALARM x SETUP RELAY CONFIG WeAlarm 1 gt B set Point 20 B Ki Failsafe NO Alarm 2 gt Dead Band 1 K2 Failsafe NO Alarm 3 Fail gt ON Delay Os K2 Acknowledge NO Relays Config gt OFF Delay Om K2 Refresh Of f Alarm Event Log gt Low Trip NO always Failsafe Latching EVENT LOG Edit 08 12 04 03 17 A1 IN 08 13 04 02 18 B Display Event Log 08 12 04 03 51
51. nsor head cover by CAREFULLY screwing the cover onto the sensor head NOTE IF THE SENSOR FALLS OUT OF THE SOCKET DURING THIS STEP IT CAN BE DAMAGED USE CAUTION WHEN REINSTALLING THE COVER At the GASMAX II activate the Main Menu open the Sensor Information page and select Install New Sensor This will reset the Sensor Life settings and tell the GASMAX that a new sensor is available Page 41 GASMAX II Operation amp Maintenance Manual Revision 4 0 MAIN MENU setup variables are stored in non volatile memory and can be modified by the end user to better match a particular application The GASMAX Main Menu tree is shown below To access the Main Menu swipe the magnetic wand over the EDIT key Pressing EDIT from either data display enters the LEL or EC SETUP PAGE 1 menu ii Key Sequence 4 consecutive UP strokes LEL INPUT 1 SYSTEM CONFIG PG 17 SYSTEM CONFIG PG 2 4 p CURVE Config Measurement 16 y B Readout Deadband BA press Enter Sesuence m Alarm Settings gt Eunits WHHHHNHNHH 10 Doww Trac
52. nual Revision 4 0 complete the SPAN GAS calibration If the SPAN calibration is successful the display flashes REMOVE CAL GAS and starts the CAL PURGE delay 5 Immediately shut off the regulator and remove the calibration cup At the end of the CAL PURGE delay the GASMAX EC output is re enabled and the unit is fully operational The flow chart shown in Figure 5 2 illustrates the above procedure UP CAL NEXT amp EDIT labels indicate keystrokes using the magnetic wand ZERO or SPAN calibration will fail if the readings exceed built in limits for maximum allowable zero or minimum allowable span NOTE A CAL MODE INFO SCREEN IS AVAILABLE TO VIEW CERTAIN CAL MODE PARAMETERS DURING CALIBRATION HOLD THE UP KEY FOR 5 SECONDS DURING CAL MODE TO DISPLAY THIS SCREEN live reading Eunits Counts Cal Span Ualuezxxxxxx EDIT Set Walue Offset xxxx CAL MODE info screen use to change SPAN GAS value and to see Offset Gain constants ain PGA HEAT Return to Cal Hold UP key 5 sec Hold UP key 5 sec Back to DATA DATA DISPLAY DISPLAY 2 5 CAL then EDIT HRP ls NExT KEY HEELS Next REMOVE units uai S m BH BHS LEL Er oe 4 LEL i Hen NEXT SPAN CAL Mode CAL Mode UEM EDIT If ZERO Cal Fails If ZERO Cal OK show for 5 seconds EDIT If SPAN
53. or replacement can be readily accomplished While there are no industry standards for gas detector placement professional tools exist that can simulate leaks or spills and provide excellent guidance for locating gas detectors throughout a facility MOUNTING THE GASMAX II The GASMAX II standard enclosure is a cast aluminum explosion proof NEMA 7 enclosure Two channel GASMAX II units with dual local sensor heads include a Y adapter shown at right The GASMAX II or remote sensor should always be mounted with the sensor head opening facing down If necessary a Splash Guard p n 10 0205 should be attached if there is any chance that water or liquid spray could enter the sensor opening from below Be sure to leave sufficient room 6 8 below the sensor head to allow for air flow easy access for attachment of a Calibration Cup and or removal of the sensor head cover for sensor replacement MOUNTING A REMOTE SENSOR GASMAX remote sensors consist of a cast aluminum explosion proof junction box and stainless steel sensor head see Fig 4 3 The junction box contains a PCB with an interface for the sensor head cable and Leave 6 8 space for air wiring terminals for the three wire connection to the GASMAX monitor flow sensor head Fittings are NPT The sensor head should ALWAYS be mounted removal and calibration vertically as shown and GDS Corp recommends side entry for all conduit runs GASMAX monitors support up
54. ot found in previous generation products On board non volatile memory retains all configuration data during power interruptions Two independent 4 20 mA outputs allow for easy connection to control systems or other alarm instrumentation Additional output options include alarm relays and single or dual channel MODBUS slave interfaces Built in user prompted calibration makes it easy for one person to perform calibration and maintenance without opening the enclosure or declassifying the area A battery powered real time clock and event log allows the GASMAX II to track calibration and alarm events for later recall on the LCD readout GASMAX SENSORS For toxic gases the GASMAX supports a wide range of electrochemical echem sensors These sensors use chemical reactions to sense the presence of gases such as hydrogen sulfide chlorine sulfur dioxide and many others For combustible gases the GASMAX II offers three different choices For lowest cost and widest range traditional catalytic bead cat bead sensor is available In addition the GASMAX II supports the GDS Corp SmartIR infrared sensor or GDS IR infrared sensor The GASMAX also supports several photoionization detector PID sensors for measurement of volatile organic compounds such as benzene or toluene Channel 2 on the GASMAX II be configured for direct bridge or 4 20mA input IMPORTANT TOXIC SENSORS ARE SUBJECT TO ACCELERATED DETERIORATION IF POWE
55. peration amp Maintenance Manual Revision 4 0 CALIBRATION PROCEDURE Before beginning calibration make sure you have the following items A cylinder of calibration gas fixed flow regulator and an appropriate calibration cup connected to the regulator via a length of flexible tubing If necessary a cylinder of zero air may be necessary if the absence of target gas cannot be confirmed GDS Corp recommends a flow rate of 0 5 liters minute for standard gases and a flow rate of 1 0 liters minute for highly reactive gases such as chlorine or chlorine dioxide Flexible Tubing SS MC 2 Fixed Flow Regulator ya Cylinder of Calibration Gas Calibration Cup To calibrate a GASMAX II detector 1 For dual channel units press the NEXT key until that the DATA Display screen for the desired channel is shown 2 Toenter CAL MODE press the DOWN CAL key and within 5 seconds press the EDIT key 3 The screen will display an APPLY ZERO message Using the setup shown in Fig 5 1 apply clean ZERO air unless it can be guaranteed that no target gas is present After the reading stabilizes press the EDIT key to complete the ZERO calibration 4 Ifthe ZERO CAL SUCCESSFUL message is displayed an APPLY SPAN message will appear Apply the correct SPAN gas After the reading is stable approximately 1 minute press the EDIT key to Page 37 GASMAX II Operation amp Maintenance Ma
56. pply PCB mounted in the back of the enclosure by a short ribbon cable Route the power and signal wires through the conduit entry and connect to terminal block TB2 Plus 24VDC connects to TB2 1 DC Ground connects to TB2 4 Channel One 4 20mA output is available on TB2 2 and Channel Two 4 20mA output is available on TB2 3 GDS Corp always recommends using shielded wire for signal and power cable TB2 1 12 30VDC Input TB2 2 Channel 1 4 20mA Out TB2 3 Channel 2 4 20mA Out TB2 4 Power Signal Common NOTE The maximum distance 4 20 mA signals can travel is dependent upon cable gauge DC power supply voltage level and input impedance of the receiving device Assuming a nominal 24 VDC power supply the maximum total loop resistance is approximately 750 ohms Examples 18GA 0 0064 ohm ft gt 11 miles 24GA 0 026 ohms ft gt 2 7 miles Figure 4 2 GASMAX II Power amp Signal Wiring OPTIONAL RELAY MODBUS INTERFACE The optional 10 0234 Relay Modbus board is connected piggyback to the back of the GASMAX II Display Assembly and supplies two level alarm relays K1 and K2 a FAULT relay K3 and an RS 485 Modbus RTU slave port If dual isolated 4 20mA outputs are not installed GASMAX II units may be field upgraded with this option at any time Page 15 GASMAX II Operation amp Maintenance Manual Revision 4 0 RELAY FUNCTIONALITY Alarm relays are dry contact SPDT and ma
57. processing will trigger an alarm condition when the input exceeds the programmed value and includes hysteresis to keep the alarm from rapidly switching ON and OFF if the input remains close to the programmed alarm value NOTE ALARM RELAYS ARE NORMALLY TRIGGERED IF EITHER CHANNEL 1 OR CHANNEL 2 ALARM THRESHOLDS ARE EXCEEDED NOTE IF THE OPTIONAL ALARM RELAYS ARE NOT INSTALLED ALARM SETTINGS AFFECT THE OPERATION OF THE FRONT PANEL LEDS ONLY SEPARATE ALARM SETTINGS MAY NEED TO BE PROGRAMMED IN THE 4 20MA RECEIVING DEVICE ALARM OPERATION ALARM 3 ALARM 3 is typically used to indicate FAULT conditions that suggest sensor failure or out of measurement range conditions However some applications require a third level alarm The ALARM 3 menu is identical to ALARM 1 and ALARM 2 and may be set to trip at any level NOTE ALARM 3 WILL ALSO TRIP WITH MISSING OR FAILED SENSORS REGARDLESS OF THE PROGRAMMED LEVEL VALUE Page 35 GASMAX II Operation amp Maintenance Manual Revision 4 0 CALIBRATION OVERVIEW Calibration is critically important to ensure correct operation of the GASMAX II The built in CAL MODE function is designed to make calibration quick easy and error free a successful ZERO and SPAN calibration requires only four keystrokes During CAL MODE zero and span the sensor output is disconnected and the GASMAX transmits a fixed mA value called the CAL MARKER to notify the receiving device that a calibration is in progress Du
58. re or discoloration FAULT indication generally indicates sensor useful life is exhausted Toxic sensors left unpowered for more than 3 months are subject to accelerated degradation and may demonstrate a permanent loss of sensitivity TOXIC SENSOR WILL NOT CALIBRATE Sensor reading during zero calibration exceeds upper limit of zero sensor is defective and should be replaced Sensor reading during span calibration too low sensor may be defective However it may be possible to temporarily continue operation by increasing PREAMP GAIN See Section 8 2 for more details BRIDGE SENSOR INDICATES FAULT OR OVERRANGE Catalytic bead combustible sensors generally indicate off scale high at power up and quickly drift towards zero as they reach operating temperature This is normal behavior Combustible sensors showing constant FAULT may have drifted below FAULT alarm level Try readjusting SENSOR BALANCE to clear FAULT If unsuccessful replace sensor Combustibles sensors showing constant OVERRANGE may have defective bead If remote check wiring for correct excitation voltage at sensor Replace sensor BRIDGE SENSOR WILL NOT CALIBRATE Sensor reading during zero calibration exceeds limits readjust SENSOR BALANCE to reset zero if possible If not sensor is defective and should be replaced Sensor reading during span calibration too low sensor may be defective However it may be possible to temporarily continue operation by inc
59. reasing PREAMP GAIN See Section 8 2 for more details RECEIVING DEVICE AND GASMAX DISPLAYED VALUES DON T MATCH Page 59 GASMAX II Operation amp Maintenance Manual Revision 4 0 Check that zero and full scale range values match between GASMAX and receiving device controller Use DIAGNOSTICS menu to force GASMAX II output to 12mA 1 2 scale and verify appropriate half scale reading on controller Check for high impedance shorts to ground on 4 20mA wiring If 4 20mA output is off scale low or high and cannot be adjusted using DIAGNOSTICS mode Supply board may be defective and should be replaced CONTROLLER MODBUS DATA INCORRECT Verify that MODBUS master is requesting data from correct registers 31001 for channel 1 toxic 31002 for channel 2 combustible Verify that controller MIN and MAX count settings are correct MIN counts should be 200 which corresponds 4mA and MAX counts should be 1000 which corresponds to 20 mA Verify that the GASMAX MODBUS address matches the address programmed into the controller s channel configuration CONTROLLER SHOWING MODBUS COMM ERROR Check for incorrect MODBUS polarity swap A and B if unsure no damage will occur Verify that MODBUS master is requesting data from correct MODBUS address Verify that MODBUS master is requesting correct registers 31001 for channel 1 toxic 31002 for channel 2 combustible Verify that there are no other
60. res a full complement of user accessible MODBUS registers that can provide complete snapshot of each gas detectors configuration This includes all real time data preset zero span and calibration values and user programmable text LIST OF GASMAX 1 MODBUS VARIABLES ChiMarmi 0 0 1 Alarm 1 Modbus Coils read Modbus Coils readonly 58 NA s 2 568 2 WA 9 9 93 9 9 9 Mew erea 8386 N amp oOo n __ __ ____ Ch 1 Sensor Life 31009 4 N A 16 bit signed integer ranging from 1 to 100 where 1 indicates Cal Required Ch 2 Sensor Life 31010 4 N A 16 bit signed integer ranging from 1 to 100 where 1 indicates Cal Required Ch 1 Sensor Temp 31011 N A 16 bit integer from 1 to 4095 scaled for 55 C to 125 C Ch 2 Sensor Temp 31012 N A 16 bit integer from 1 to 4095 scaled for 55 C to 125 C Page 55 GASMAX II Operation amp Maintenance Manual Revision 4 0 _ rcason mm 3 WA Fchacalspanbvsor 3 WA 6 a me a misma mm a WA 69 9 468 a wa mw 3 NA
61. ring the following CAL PURGE DELAY time the GASMAX II transmits a fixed 4 0 mA signal to prevent external alarms during calibration In the case of local or remote Oxygen sensors during CAL PURGE DELAY the output simulates a typical atmospheric reading of 20 8 CAL MODE automatically exits if no keystrokes are detected after 5 minutes Follow these GASMAX II calibration guidelines e Calibration accuracy is only as good as the calibration gas accuracy GDS Corp calibration gases are traceable to NIST National Institute of Standards and Technology e Never use calibration gas that has passed its expiration date e Check the SPAN GAS VALUE setting and make sure it matches the calibration gas See Fig 6 2 e Always use GDS Corp calibration cup that completely surrounds the sensor head e Be sure to use ZERO AIR a mixture of 21 oxygen and 79 nitrogen as a zero reference unless you are certain that no target gas exists in the area Ambient gas may result in an elevated zero condition that will cause a FAULT to occur once the ambient gas is no longer present e Always calibrate a new sensor before depending on the device for personnel or equipment safety Calibrate on a regular schedule GDS Corp recommends full calibration every 3 months with periodic bump tests on a more frequent basis to ensure that the sensor has not been affected by temperature extremes or the presence of incompatible gases Page 36 GASMAX O
62. sembly e Do not operate the GASMAX if its enclosure is damaged or cracked or has missing components Make sure the cover internal PCB s and field wiring are securely in place before applying power e not expose the GASMAX II to electrical shock or continuous severe mechanical shock Protect the GASMAX and related sensor assemblies from dripping liquids and high power sprays e Calibrate with known target gas at start up and check on a regular schedule at least every 90 days More frequent inspections are encouraged to spot problems such as dirt oil paint grease or other foreign materials on the sensor head e Periodically test for correct operation of the system s alarm events by exposing the monitor to a targeted gas concentration above the High Alarm set point e Use only for applications described within this manual Page 10 GASMAX Operation amp Maintenance Manual Revision 4 0 The GASMAX II is a single or dual channel fixed point gas monitor designed to provide continuous monitoring of toxic or combustible gases in hazardous areas Gas values are displayed in calibrated engineering units as well as bar graph or 30 minute trend graph format The GASMAX II supports one or two local or remote mount sensors for toxic or combustible gases The advanced microcontroller non intrusive magnetic interface and superior graphic LCD interface offers rapid setup simplified operation and enhanced diagnostics n
63. tenance Manual Revision 4 0 II Single Dual Channel Gas Monitor Power Input 10 30VDC at lt 4 watts with relay board Additional power required for Extended Temp amp GDS IR option Display 64 x128 pixel LCD with engineering units bargraph and 30 minute trend Channel One Microamp level input for local or remote GDS Corp toxic gas sensors Input Optional 4 20mA input for remote sensor transmitters GDS IR GDS 50 or other 4 20mA source Channel Two Bridge type input with adjustable excitation voltage for local or remote Catalytic Bead Input SmartIR or PID sensor Optional 4 20mA input for remote sensor transmitters GDS IR GDS 50 or other 4 20mA source 5 of full scale typical Standard Dual three wire 4 20mA current source outputs with fault and overrange indication Maximum loop resistance is 750 ohms with standard 24VDC supply Fault output 0 0 mA for all fault conditions Optional Relay MODBUS interface with 3x 5A SPDT programmable alarm relays Output Dual isolated 4 20mA outputs Single or dual input MODBUS slave interface no relays Electronics 40 C to 60 C See Sensor Manual for additional details On board non volatile memory retains all user settings Housing Aluminum housing with epoxy paint standard 316 stainless steel optional One 54 NPT female connection for local sensor head Two 34 NPT female connections for conduit or cable glands Dimensions Width 5 4
64. um 120 minute delay before clearing an alarm after the alarm condition is gone This is useful for continuing an alarm function such as operation of an exhaust fan for a period of time after the alarm condition clears LOW TRIP set to YES causes the alarm to trip as the value falls below the set point LATCHING set to YES causes the alarm to remain active even after the condition is gone and only reset when the UP RESET key is pressed from a data display DISPLAY EVENT LOG displays the stored events in the Event Log These include power on cold boot alarms and alarm acknowledge events The event log stores the date and time of the most recent 300 events CLEAR EVENT LOG clears the event log RS 485 COMMUNICATIONS The RS 485 MODBUS SETUP menu allows setting the RTU address if RS 485 equipped for each GASMAX on the RS 485 network Each GASMAX must have a different RTU address when communicating on the same 2 wire cable RS 485 loop Baud rate Parity and Stop Bit are fixed at industry standard values of 9600 baud No Parity and One Stop Bit 85485 MODBUS SETUP gt RTU Address 1 Baud Rate 9600 Parity None Stop Bit 1 Figure 8 5 RS 485 MODBUS Menu SENSOR SETUP The Sensor Information page covers settings associated with Smart or simple sensors Users can review information contained in the Smart Sensor database or adjust settings for remote simple sensors Page 46 GASMAX II Operation amp Maintenance Manual
65. use with local or remote GDS IR Infrared Combustible Sensors or GDS 49 Remote Toxic Sensor Transmitters Wiring examples are shown on the next page 1 10 0233 D4 1 24VDC 10 0233 D4 2 Channel 2 Analog In Dual 4 20mA Input C 3 Common CJL 4 Channel 1 Analog In 10 0233 B4 4 20mA In Bridge In 10 0233 D420 PWR OUT 1 IO Power Supply bbon to Display TB2 2 1 10 0233 4 1 24VDC Supply 1 R terminal for cat bead 2 Channel 1 4 20mA Out 2 C terminal for cat bead 3 Channel 2 4 20mA Out 3 A terminal for cat bead 4 Power Signal Common 4 Channel 1 4 20 Analog In Figure 4 16 Dual 4 20mA Input Option Page 29 GASMAX II Operation amp Maintenance Manual Revision 4 0 Once installed apply power to the GASMAX II and verify that the LCD display is active Certain sensors may initially indicate off scale high or low values but should quickly return to zero if no target gas is present During this warm up delay period the 4 20mA output is held at 4 0 mA to eliminate false alarms in any receiving devices Warm up delay is one of the user adjustable parameters LOCAL TOXIC SENSOR SETUP The GASMAX II automatically loads all necessary setup information from locally connected toxic sensors via the 10 pin sensor cable No user setup is required NOTE IF ALOCALLY CONNECTED TOXIC SENSOR IS NOT RECOGNIZED VERIFY THAT THE SENSOR CABLE IS PLUGGED IN AS
66. ut range for the GASMAX II signal conditioning circuits Local Smart Sensors include factory preset preamp gain values and for standard sensors and applications these values should not be changed For remote simple sensors or for situations where a local Smart Sensor does not quite provide enough signal to successfully complete a SPAN calibration the Preamp gain can be adjusted using the UP DOWN keys GDS Corp does not recommend adjusting the Preamp Gain to any value higher than 8596 WARNING A FULL CALIBRATION SHOULD ALWAYS BE PERFORMED AFTER ANY CHANGE IN THE PREAMP GAIN SETTING Page 52 GASMAX II Operation amp Maintenance Manual Revision 4 0 PGA Setup Gain 25 0 Counts 10 11 Reading 100 Up Dn to Change Next to exit Figure 9 5 PREAMP GAIN SET MENU Simple Sensor Input Type Local Smart Sensors automatically configure Input Type to match sensor requirements However when using remote sensors Input Type must be set manually Input Type is factory preset and should not be changed unless a different TYPE remote sensor is to be installed Input Type configures GASMAX hardware to accept bridge sensors positive coefficient electrochemical sensors negative coefficient electrochemical sensors or 4 20 mA inputs After selecting Input Type a SELECT EUNITS screen indicates the default engineering units for this sensor Electrochemical Sensor Type Default EUNITS Negative Negative Negative Negative Bias
67. ut shares the same common ground and are therefore not isolated from each other This board is connected piggyback to the back of the GASMAX II Display Assembly GASMAX units may be field upgraded with this option at any time NOTE ISOLATED 4 20MA AND MODBUS RELAY BOARDS SHARE THE SAME CONNECTOR AND THEREFORE CANNOT BE INSTALLED SIMULTANEOUSLY TB1 Isolated Dual 4 20mA Output 1 out 100250 20 EC Out 3 Let out O 4 O teot O Figure 4 7 Optional Dual Isolated 4 20mA Output Page 19 GASMAX II Operation amp Maintenance Manual Revision 4 0 LOCAL SMART TOXIC SENSOR CH1 Local toxic sensors are factory installed in a sensor head directly attached to the GASMAX enclosure Local toxic sensors are always connected to the Channel 1 Smart Sensor connector S1 located on the back of the Display Assembly See Fig 4 5 IMPORTANT TOXIC SENSORS ARE SUBJECT TO ACCELERATED DETERIORATION IF POWER IS NOT SUPPLIED WITHIN 3 MONTHS OF SHIPMENT FROM GDS CORP Do not connect signal or power wiring to terminal block TB1 Local Toxic Sensor Cable from sensor head connects to S1 on back of display assembly Figure 4 8 Local Smart Toxic Sensor Connection Page 20 GASMAX Operation amp Maintenance Manual Revision 4 0 CONNECTING A REMOTE TOXIC SENSOR CH1 GASMAX II monitors with remote mount toxic sensors are shipped in two pieces and sensor wiring must be installed by the end user
68. y be configured as normal or failsafe normally open held closed Power must be supplied from an external source and should be fused WARNING CONTACTS ARE RATED FOR RESISTIVE LOADS ONLY INDUCTIVE LOADS SUCH AS COILS MOTORS OR SOLENOID VALVES MAY CAUSE ARCING WHICH SHORTENS LIFE AND MAY INTERFERE WITH SENSOR DATA Relay K1 activates if either Channel 1 or Channel 2 exceed the programmed alarm 1 threshold and cannot be acknowledged Relay K2 activates if either Channel 1 or Channel 2 exceed the programmed alarm 2 threshold and can be acknowledged reset from the front panel or via TB3 Relay K3 indicates sensor failure and is always failsafe normally open held closed Remote Alarm Reset TB3 can be used to acknowledge an Alarm 2 relay contact closure via a remote pushbutton Use a momentary dry contact normally open switch between and to force a reset Wiring from any remote pushbutton to TB3 should be shielded and protected from noise spikes to prevent false Alarm Reset commands A version of this board is available with MODBUS RTU slave only configuration No relays K1 MODBUS Termination Jumper A installs jumper B omits jumper MODBUS Relay 10 0234 Figure 4 3 Optional Relay MODBUS Interface Board MODBUS WIRING Typical MODBUS wiring is shown in Figure 4 6 MODBUS system architecture requires that the devices in any MODBUS loop be connected in a daisy chain layout This minimizes signal

Operation and Maintenance Manual

Contents

Download Pdf Manuals

Related Search

Related Contents