User Manual

18 • 35-3000RK-LEL Combustible Gas Sample-Draw Detector

Calibration

This section describes how to calibrate the combustible gas sample-draw detector. It

includes procedures to assemble the calibration kit, set the zero reading, set the response

reading, and return to normal operation.

The standard calibration gas for the sample-draw detector is methane. The sample-draw

detector may be calibrated to other combustible gases such as hexane or hydrogen. Use

the correct calibration gas for your installation.

NOTE: Calibrating the sample-draw detector may cause alarms. Be sure to put the

controller into its calibration program or disable external alarms before

continuing.

NOTE: This procedure describes calibration using a dispensing valve and a gas

collection bag. A demand-ﬂow regulator calibration kit is also available for

calibrating the sample-draw detector without using a sample bag.

Preparing for Calibration

1. Follow the instructions in the controller’s operator’s manual for entering calibration

mode.

2. Connect the calibration kit sample tubing to the ﬁtting on the gas collection bag and

run the tubing through the tubing clamp provided with the calibration kit.

3. Disconnect the incoming sample line from the sample-draw detector’s inlet ﬁtting,

then connect the sample tubing from the gas collection bag to the inlet ﬁtting.

Allow the sample-draw pump to draw out any residual gas in the gas collection bag.

4. Close the tubing clamp.

NOTE: This step will cause a low ﬂow alarm.

5. Disconnect the calibration kit sample tubing from the inlet ﬁtting.

NOTE: If you can verify a fresh air environment, it is not necessary to use a zero air

calibrating sample to set the zero reading at the controller. If you can verify a

fresh air environment, go to the next section, Setting the Zero Reading.

6. Screw the dispensing valve onto the zero air calibration cylinder.

7. Connect the tubing from the gas collection bag to the dispensing valve, then open the

clamp.

8. Open the dispensing valve. The gas collection bag begins to ﬁll.

9. Close the dispensing valve when the gas collection bag appears full.

10. Close the tubing clamp, then disconnect the sample tubing from the dispensing valve.

11. Remove the dispensing valve from the zero air calibration cylinder.