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Calibration, Oxygen Detector
35-3010RKA-04H Sample-Draw Detector Head
5. Store the components of the calibration kit in a safe and convenient place.
Calibration, Oxygen Detector
This section describes how to calibrate the oxygen detector in the sample-draw detector. It
includes procedures to prepare for calibration, set the zero reading, set the fresh air reading, and
return to normal operation.
NOTE:
This procedure describes calibration using a demand flow regulator, a zero air
calibration cylinder, and a nitrogen calibration cylinder to set the zero reading.
Preparing for Calibration
CAUTION:
This procedure may cause alarms at the controller. Take appropriate action to avoid
this, such as entering the calibration mode at the controller.
1. Open the housing door.
2. Set a voltmeter to measure in the millivolt (mV) range.
3. Plug the voltmeter into the test points on the oxygen transmitter. Plug the positive lead into the
test point labeled
TP+
; plug the negative lead into the test point labeled
TP-
.
Setting the Zero Reading
1. Screw the regulator into the nitrogen calibration cylinder.
2. Connect the calibration kit sample tubing to the regulator.
3. Allow the sample-draw detector to respond to the calibrating sample for approximately 1
minute.
4. After one minute, check the mV output on the oxygen transmitter test points and verify a
reading of 100 mV (±2 mV).
5. If necessary, use the span pot on the transmitter to adjust the reading to match the correct
response reading.
6. Disconnect the sample tubing from the inlet line.
7. Unscrew the regulator from the nitrogen calibration cylinder.
8. For convenience, leave the regulator attached to the sample tubing.
