65-2646RKS-SW M2A Transmitter Operator’s Manual
Chapter 7: Maintenance
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10. Calibrate the transmitter as described in the “Calibration” on page 36.
Replacing the CO Detector
NOTE:
In most cases, it is only necessary to replace the plug-in CO sensor.
1. Turn off or unplug power to the M2A.
2. Remove the junction box cover.
3. Grasp the control PCB by its edges.
4. Gently pull until the control PCB is pulled away from the banana jacks. Take care not to pull
too hard and damage the cable which connects the control and terminal PCBs.
5. Let the control PCB hang by the cable. The terminal strips are now visible on the terminal
PCB. The control PCB may be left hanging while wiring is done. If desired, the control PCB
may be disconnected from the cable and set aside while wiring.
6. Remove the detector terminal strip from its socket.
7. Disconnect the detector leads from the detector terminal strip. Note the position of the color-
coded leads as you remove them.
8. Unscrew the detector from the junction box.
9. Guide the detector leads of the replacement detector through the bottom conduit hub of the
junction box, then screw the mounting threads of the detector into the conduit hub. If
necessary for environmental conditions, apply thread sealant or Teflon tape to the hub and/or
detector threads to seal them.
10. Connect the detector leads to the detector terminal strip. Make sure the red wire is connected
to the terminal labeled TOXIC + and the black wire is connected to the terminal labeled
TOXIC -(see Figure 7 on page 17).
11. Re-install the detector terminal strip into its socket.
12. Re-install the control PCB (and ribbon cable if necessary). Be sure the ribbon cable is routed
down below the control PCB so it will not be damaged by the cover when it is screwed back
on.
13. Reinstall the junction box cover.
14. Turn on or plug in power to the M2A.
CAUTION:
Allow the replacement detector to warm up for 5 minutes
before you
continue with the next step.
15. Calibrate the replacement detector as described in “Calibration” on page 36.
