35-3001A-09 Oxygen/Hydrogen Sulfide Sample-Draw Detector • 17
4. Unscrew and remove the two screws that secure the H
2
S amplifier, then lift the H
2
S amplifier
and sensor off of the flow block.
There is a gasket at the bottom of the flow block. Be sure the gasket stays in place.
5. Unplug the sensor from the H
2
S amplifier.
6. Verify that you are using the correct replacement sensor, then plug the sensor into the H
2
S
amplifier.
7. Place the sensor and amplifier in the H
2
S sensor cavity.
8. Secure the H
2
S amplifier on the flow block with the two screws you removed in step 4.
9. Close and latch the housing door.
10. Turn on power to the controller.
11. Turn on the controller.
CAUTION:
Allow the replacement sensor to warm up for 5 minutes before you continue.
12. Calibrate the replacement sensor as described in “Calibration, H
Replacing the Oxygen Amplifier
1. Turn off the controller.
2. Turn off power to the controller.
3. Open the housing door of the sample-draw detector.
4. Remove the detector and controller plug-in terminal strips by grasping the sides of the strips
with your fingers. Let the terminal strips hang by their connected wires while you replace the
amplifier.
5. Unscrew the screw in the lower left corner of the amplifier and remove the screw, lock washer,
and flat washer. Be careful not to lose any of these parts.
6. Remove the old amplifier from the main circuit board.
7. Install the new amplifier in the same orientation as the old amplifier. See Figure 1.
8. Reinstall the screw, lock washer, and flat washer you removed in step 5.
9. Install the detector and controller plug-in terminals strips into their sockets on the new
amplifier. If controller leads or detector cable leads were removed from the plug-in terminal
strips during this procedure, refer to Table 2 and Table 3 below.
Table 2:Reconnecting the Amplifier to the Amp 1 Terminals
on the Detector/Amp Terminal Strip
Amplifier Controller
Terminal Strip
Detector/Amp Terminal
Strip on Main PCB
SIG/PWR “S”
AMP 1 “S”
SIG/PWR “+”
AMP 1 “+”
