14 • 65-2443 PPM Hydrogen Transmitter
Replacing Components of the PPM Hydrogen Transmitter
This section includes procedures to replace the ppm hydrogen detector and amplifier.
Replacing the PPM Hydrogen Detector
1. Turn off power to the controller.
2. Place the controller’s on/off switch in the OFF position.
3. Remove the junction box cover.
4. Remove the detector terminal strip from its socket.
5. Disconnect the detector leads from the detector terminal strip. Note the position of the color-coded
leads as you remove them.
6. Unscrew the detector from the junction box.
7. 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.
8. Connect the detector leads to the detector terminal strip as shown in Table 3 below and Figure 4 on
page 11 of this manual.
9. Re-install the detector terminal strip into its socket.
NOTE:
When a transmitter is first powered up with a new detector, its output may be high enough to
cause an alarm or low enough to indicate a failure for a brief period before stabilizing within
a few minutes. Be sure to make arrangements so that this does not cause unwanted alarms.
10. Turn on power to the controller.
11. Turn on the controller and place it into normal operation.
12. Allow the transmitter to run for 3 hours.
13. Perform a preliminary calibration as described on page 16. This will be a temporary calibration
since the new ppm detector must burn-in before it can be properly calibrated.
14. Allow the replacement detector to burn-in for at least 5 days
before you continue with the next
step. A burn-in period of 7 days is recommended.
15. After the burn-in period, calibrate the transmitter as described on page 16.
Table 3:Reconnecting the PPM Detector to the Amplifier
Detector Lead
Detector Terminal Strip
Red
R
White
W
Black
B
