User Manual

35-3010RKA-02 Sample-Draw Detector • 21

3. Connect the sample tubing from the regulator to the inlet line at or near the INLET

fitting.

4. Allow the g as to fl ow for one minute.

5. Verify a voltmeter reading of 100 mV ± 2 mV at the test points as described in the

Preparing for Calibration section above.

6. If necessary, use a small flat-blade screwdriver to adjust the zero pot until the

voltmeter reading is 100 mV ± 2 mV.

7. Disconnect th e sample tubing from the inlet line.

8. Unscrew the regulator from the zero air calibration cylinder. Leave the sample tubing

connected to the regulator.

Setting the Response Reading

1. Screw the regulator into the 4-gas calibration cylin der.

2. Connect the sample tubing from the regulator to the inlet line at or nea r the sample-

draw detector’s INLET fitting.

3. Allow the ca libration gas to flow for one minute.

4. Check the mV output on the LEL transmitter test points and verify that the reading

matches the response reading (±2 mV) you determined earlier.

5. If necess ary, use the span pot on the LEL transmitter to adjust the r eading to match the

correct response reading.

6. Disconnect the samp le tubing from the sample-draw detector’s inlet line.

7. Unscrew the regulator from the calibration cylinder.

NOTE: For convenience, leave the regulator connected to the sample tubing.

Returning to Normal Operation

1. Remove the voltmeter leads from the test points.

2. Reconn ect the incoming sample line.

3. Wait 1 to 2 minutes to allow the calibratio n gas to be drawn out and the reading to

stabilize.

4. Close the housing door.

5. Store t he c omponents of the calib ration kit in a safe and co nvenient place.

Calibration, Oxygen Detector

This se cti on de scri be s h ow t o c ali br ate the ox ygen 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, a nd a 4-gas calibration cylinder. A 4-gas cylinder is used to

set the zero since it is already used to calibrate the LEL and H

S channels. A

100% nitrgoen calibration cylinder could also be used to set the zero reading.