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65-2660RK-XX-04 M2A Transmitter Operator’s Manual

33

Chapter 7: Maintenance

Overview

This chapter describes procedures for performing preventive maintenance, troubleshooting, calibrating the M2A, 
and replacing field replaceable parts. 

Preventive Maintenance

This section describes a recommended preventive maintenance schedule to ensure the optimum performance of 
the M2A. It includes daily and biannual procedures.

Daily

Verify a display reading at the controller of the background concentration of CO

2

. Typical background 

concentrations of CO

2

 vary from about 300 to 600 ppm (0.03 to 0.06 %volume) depending on location.

Biannually

Calibrate the M2A as described in “Calibration” on page 36. See “Calibration Frequency” on page 35 for a 
discussion of calibration frequency guidelines.

Troubleshooting

The troubleshooting guide describes symptoms, probable causes, and recommended action for problems you 
may encounter with the M2A.

NOTE:

This troubleshooting guide describes M2A problems only. If the M2A is connected to a controller, 
see the controller operator’s manual for problems you may encounter with the controller.

Table 7: Troubleshooting the IR CO

2

 Detector

Condition

Symptom(s)

Probable Causes

Recommended Action

No Power

The display backlight is 
off and the display 
screen is blank.

• The power wiring is 

disconnected or 

misconnected.

• The display cable is 

disconnected or 

misconnected.

1. Verify that the wiring to the power 

source or controller is correct and 

secure.

2. Verify that the ribbon cable 

connecting the terminal PCB to the 

control PCB is securely installed. 

This ribbon cable plugs into a 

connector on the top edge of the 

control PCB and on the bottom of the 

terminal PCB.

3. If the power difficulties continue, 

contact RKI for further instruction.

Summary of Contents for 65-2660RK-XX-04

Page 1: ...RKI Instruments Inc www rkiinstruments com 65 2660RK XX 04 M2A Transmitter Operator s Manual Part Number 71 0428 Revision F Released 8 28 20...

Page 2: ...h Periodic calibration and maintenance of the gas monitor is essential for proper operation and correct readings Please calibrate and maintain this instrument regularly Frequency of calibration depend...

Page 3: ...or replacement costs local repair costs transportation costs or contingent expenses incurred without our prior approval THIS WARRANTY IS EXPRESSLY IN LIEU OF ANY AND ALL OTHER WARRANTIES AND REPRESENT...

Page 4: ...n 8 Internal Description 10 Chapter 3 Installation Startup 14 Overview 14 Mounting the M2A Transmitter 14 Wiring the M2A Transmitter 16 Start Up 20 Chapter 4 Operation 22 Overview 22 Normal Operation...

Page 5: ...ime 35 Calibration 36 Replacing the IR CO2 Detector 38 Chapter 8 RS 485 Modbus Output 40 Overview 40 Wiring the M2A in a Modbus System 40 Using the M2A in a 4 wire Modbus System 43 Modbus Mode 43 Supp...

Page 6: ...ch is visible through the window in the cover front face and provides a 4 20 mA signal which indicates the target gas reading for use by a gas monitoring controller recording device or programmable co...

Page 7: ...1 volume 0 1 volume 1 volume Alarm 1 2 000 ppm 2 500 ppm 0 50 volume 50 0 volume 100 volume Alarm 2 5 000 ppm 5 000 ppm 3 00 volume 50 0 volume 100 volume Construction housing Explosion proof Junction...

Page 8: ...re the detector needs to be installed at an inaccessible location The detector junction box can be installed at the inaccessible location and the M2A junction box can be installed in a more readily ac...

Page 9: ...nal strip The other side of the terminal strip is for user supplied wiring to the detector terminal strip located in the M2A junction box This wiring should go through the top 3 4 NPT conduit hub Thre...

Page 10: ...range and an RS 485 Modbus output signal The 4 20 mA signal may be used by a recording device gas monitor controller or programmable controller The Modbus output may be used to connect the M2A to a Mo...

Page 11: ...page 16 for all wiring procedures related to M2A Modbus Terminal Strip The Modbus terminal strip is a three position plug in style terminal strip and is the bottom terminal strip in the left terminal...

Page 12: ...nana jacks in the terminal PCB mounting standoffs and pushing it onto the banana jacks The jacks retain the control PCB Figure 4 Control PCB Component Location OLED Display The OLED display is located...

Page 13: ...e 4 Fail LED The fail LED turns on when the M2A is experiencing a fail condition A fail condition can be caused by a detector failure or low detector signal Alarm 1 LED The alarm 1 LED is on when the...

Page 14: ...to perform start up maintenance and calibration procedures The site should be easily accessible Mount the detector junction box near the floor where CO2 is likely to be found first The junction boxes...

Page 15: ...le polyurethane tubing to the fitting at the bottom of the calibration adapter splash guard and route it to an accessible area that is close to the M2A junction box See the Chapter 9 Parts List on pag...

Page 16: ...h the top conduit hub of the detector junction box To make wiring more convenient use wire colors that correspond to the detector wire colors red white green and black 9 Connect the wires to the termi...

Page 17: ...he opposite end of the cable s drain wire to the M2A junction box s chassis earth ground Figure 7 Wiring the Detector to the M2A 14 Reinstall the detector terminal strip into its socket 15 If shielded...

Page 18: ...B PLC and DCS Device Wiring on page 52 then continue with step 8 Use the following recommendations to determine how to wire the M2A If Modbus connections will not be used and only the PWR SIG connect...

Page 19: ...e junction box 5 Make controller device and relay connections as appropriate If shielded cable is used for the PWR SIG connections connect the cable shield s drain wire to an available chassis ground...

Page 20: ...used to zero an M2A with a high range detector 0 50 volume or 0 100 volume Non Intrusive Fresh Air Signal Adjustment If the M2A is installed in a classified area and non intrusive zero adjustment is r...

Page 21: ...display line 4 Screw the 100 N2 cylinder into the fixed flow regulator 5 Use the flexible tubing coming from the calibration adapter splash guard to connect the regulator to the calibration adapter 6...

Page 22: ...ng in a fresh air environment The high range detectors 0 50 volume and 0 100 volume detectors will not display a reading in fresh air Information Screen The Information Screen displays the M2A s opera...

Page 23: ...peration If the M2A s input power decreases below 18 5 volts so that the M2A is in a low power alarm the signal output is fixed below 2 4 mA until the low power alarm is cleared If the M2A goes into a...

Page 24: ...to reset the alarm 1 circuit Resetting the alarm 1 circuit turns off the A1 LED resets the OLED display and de energizes the alarm 1 relay NOTE If the ENTER button is pressed while the M2A is in an a...

Page 25: ...on Fail Condition Indications The M2A indicates a fail condition for any of the following The detector wiring is disconnected or incorrectly connected The display reading is 10 of full scale or lower...

Page 26: ...sequence Responding to a Low Power Condition 1 Determine and correct the cause of the low power condition 2 When the input power increases above 10 0 volts the M2A will begin its warm up sequence 3 Ve...

Page 27: ...the following screen appears 2 If you want to exit Configuration Mode press and release the DOWN NO button and the M2A will return to normal operation If you want to continue in Configuration Mode pr...

Page 28: ...e gas reading at which the M2A initiates an alarm 2 condition ALARM 2 activation Increase Indicates if the alarm 2 circuit is activated by gas readings increasing Increase or decreasing Decrease to th...

Page 29: ...ther than 0 0 such as 1 0 the M2A will display a reading of 0 0 for gas readings from 1 0 volume to 1 0 volume The zero suppression is settable from 0 to 6 of the detection range FILTER 5 secs The fil...

Page 30: ...he Gas Type 1 While in normal operation or during the warm up sequence press and hold the UP YES and DOWN NO buttons for five seconds Release them when the following screen appears 2 If you want to ex...

Page 31: ...pressing the ENTER button display will ask SAVE IT YES NO 8 To save the configuration settings press and release the UP YES button The display will indicate Config Saved and the M2A will begin its war...

Page 32: ...n calibrating an M2A after changing the gas type the M2A will not ask if you want to calibrate or whether you want to perform a fresh air adjustment span adjustment or zero adjustment Since a complete...

Page 33: ...Troubleshooting The troubleshooting guide describes symptoms probable causes and recommended action for problems you may encounter with the M2A NOTE This troubleshooting guide describes M2A problems...

Page 34: ...hielded See Wiring the M2A Transmitter on page 16 2 Verify that the detector wiring is correct and secure 3 Increase the filter setting in Configuration Mode 4 Increase the zero suppression setting in...

Page 35: ...calibration adapter splash guard 5 Turn the regulator s on off knob counterclockwise to open the regulator Gas will begin to flow Take note of the time or start a stopwatch 6 When you first start to n...

Page 36: ...with a CO2 concentration between 500 and 5 000 ppm NOTE While in the calibration program if there is no switch activity for the calibration time out period the unit will return to normal operation See...

Page 37: ...next section Adjusting the Span Setting 4 Screw the 100 N2 cylinder into the fixed flow regulator 5 Use the flexible tubing coming from the calibration adapter splash guard to connect the regulator to...

Page 38: ...ector remove it now to avoid unwanted alarms During this 1 minute period the signal output will remain fixed at 3 5 mA and the relays will remain in their non alarm state to avoid unwanted alarms whil...

Page 39: ...install the detector junction box cover 10 Turn on or plug in power to the M2A NOTE Allow the replacement detector to warm up for 15 minutes before you continue with the next step 11 Calibrate the rep...

Page 40: ...e 12 below illustrate typical M2A wiring configurations If more than 128 M2As need to be connected together RS 485 repeater s should be used such that no more than 128 M2As reside on any given network...

Page 41: ...s should only be done if wiring for a system that is being replaced is already installed and it is not practical to run another wire See Figure 10 below for this wiring configuration In this configura...

Page 42: ...in an M2A that is at the end of a Modbus line Any M2A in a Modbus system that is not at the end of a line must have the termination jumper removed see Figure 11 Figure 12 below Figure 11 Multiple M2As...

Page 43: ...atically returns to normal operation NOTE If the M2A returns to normal operation because of a time out it enters a warm up period just as it does when it is first turned on 1 While in normal operation...

Page 44: ...normal operation NOTE All M2As on a Modbus network must be configured with the same baud rate and parity and each M2A must have a unique slave ID For an M2A to participate on a network the ENABLED DI...

Page 45: ...Reading with Sign Decimal Point Bit Field Assignments Bit s Value Field 15 Sign of Reading 0 Positive 1 Negative 14 13 Format of Reading 0 XXX no decimal point 1 XX X 2 X XX 3 XXX 12 0 Numerical value...

Page 46: ...1 Register 14 Register 14 is the alarm 2 set point The decimal point location is the same as specified in Register 1 8 Fail Status 0 Fail Not Asserted 1 Fail Asserted 7 6 Alarm 2 Status 0 No Alarm 1...

Page 47: ...rm 1 relay reset 0 Latching 1 Self Resetting Register 26 Register 26 is the alarm 1 ON delay Integer values are in seconds Register 27 Register 27 is the alarm 1 OFF delay Integer values are in second...

Page 48: ...y 0 and the 1st 0 Register 37 Register 37 is the calibration year Register 38 Register 38 is the calibration outcome Upper Gas Operation Lower Air Operation Calibration Outcome Codes 1 Sensor Missing...

Page 49: ...unction Code 16 see Appendix C Function Code 16 Registers on page 54 Register 16 Register 16 performs the same function as the ENTER button on the M2A It is useful for remotely silencing alarms With t...

Page 50: ...gen 34 liter steel 81 0070RK 03 Calibration cylinder 2 000 ppm CO2 in nitrogen 103 liter 81 0071RK 01 Calibration cylinder 5 000 ppm CO2 in nitrogen 34 liter steel 81 0071RK 03 Calibration cylinder 5...

Page 51: ...Button Quick Reference Chart Mode Entered or Function Performed Button Combination Adjustable or Viewable Parameters Alarm Reset Press and Release ENTER n a Show Information Screen Press and Hold DOW...

Page 52: ...he PWR SIG terminal strip connections and one or more relays are used route the connections to the M2A in conduit Use shielded cable in the conduit for the PWR SIG connections and unshielded cable or...

Page 53: ...PLC and DCS Device Wiring Alarm Device Power Fail Alarm Device Alarm 1 Alarm Device 24 VDC 24 VDC Power Supply 24 VDC Typical Alarm Wiring Shown 24 VDC 4 20 mA In S Alarm 2 Alarm Device C NC NO ALARM...

Page 54: ...0 Normally De Energized 1 Normally Energized Register 4 Register 4 is the alarm 1 relay reset 0 Latching 1 Self Resetting Register 5 Register 5 is the alarm 1 ON delay Integer value is in seconds Regi...

Page 55: ...5 second increments Register 15 Register 15 is the calibration timeout Value is in minutes 5 10 15 20 25 or 30 Register 16 Register 16 is explained in Supported Modbus Functions in the M2A manual Reg...

Page 56: ...2A Transmitter Operator s Manual Register 20 Register 20 is the AutoZero Disable 0 AutoZero Enabled 1 AutoZero Disabled Register 21 Register 21 is the Remote Configuration Register 0 No Remote Configu...

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