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B.
SENSOR REPLACEMENT
Sensor replacement must be followed by new sensor calibration as described in Part C of
this Section.
The tools required for sensor replacement and new sensor calibration are a Phillips #1
screwdriver and a small rod (less than 3/32" in dia.) to actuate the push-button under the 4-40
black screw on the right side of the detector (see Figure 3).
The following stepwise procedure will result in an efficient and trouble-free installation
of any sensor in the Gas-Ranger:
1.
Remove the four Phillips-head screws from the bottom of the case, lift the top cover
off and place it face down in front of the case.
2.
Remove the sensor to be replaced from the circuit board by pulling the sensor
straight up. Make certain that the rubber gaskets remain in place in the gas
manifold.
3.
Align the new sensor pins with the receptacles on board. Push directly down to
secure the sensor to the board.
4.
Place the top cover back on the base, aligning the two brass power connections over
their receptacles, and re-attach the cover to the base using the four Phillips-head
screws.
C.
NEW SENSOR CALIBRATION (SCAL)
The following procedure will calibrate the new sensor after installation
CAUTION:
SCAL must be performed after a new sensor is installed before the detector can
be used.
1.
Remove the black #4-40 screw from the right side of the detector (see Figure 3).
2.
While simultaneously pressing both RESET and the push-button on the right of the
detector, move the selector switch from OFF to TRACK GAS and wait 2-3 seconds
before releasing the buttons.
"SCAL"
should be displayed for several seconds.
Note:
If 1 or 2 dots appear, repeat Step 2.
3.
The detector automatically sets up and zeros the new sensors and calibrates the
oxygen sensor (if present) on the air sampled by the pump. When finished,
"End"
is
displayed.
CAUTION:
The detector must be sampling clean air to ensure accurate set up and zeroing.
