35-3001A-01H Hydrogen Sample-Draw Detector • 11
Start Up
This section describes procedures to start up the sample-draw detector and place the sample-draw
detector into normal operation.
Introducing Incoming Power
1. Complete the installation procedures described earlier in this manual.
2. Verify that the wiring is correct and secure. Refer to the controller operator’s manual for
connections at the controller.
3. Turn on or plug in the power to the controller, then turn on the controller.
4. Verify that the sample-draw detector’s Pilot LED is on.
5. Verify that the controller is on and operating properly. Refer to the controller operator’s
manual.
6. Verify that the flowmeter indicates a flow rate of approximately 1.0 SCFH. If necessary, use
the sensor flow control valve to adjust the flow rate. Turn the valve’s knob counterclockwise to
increase the flow and clockwise to decrease the flow.
NOTE:
The following step tests for leaks in the sample line. This test will cause a low flow
condition at the sample-draw detector and a fail condition at the controller. Be sure to put
the controller into its calibration program or disable external alarms before performing
this test.
7. Verify that the incoming sample line is not leaking. To test the sample line, press and hold the
reset switch and plug the open end of the sample line with your thumb. If the flowmeter ball
drops to the bottom of the flowmeter, the incoming sample line is not leaking.
8. Remove your thumb from the sample line, release the reset switch, and verify the flowmeter
returns to a normal flow rate.
9. Enable alarms or place the controller in normal operation.
CAUTION:
Allow the sample-draw detector to warm up for 5 minutes before you continue with
the next section, “Setting the Zero Reading.”
Setting the Zero Reading
CAUTION:
If you suspect the presence of hydrogen in the monitoring environment, use the
calibration kit and the zero air calibration cylinder to introduce “fresh air” to the
sensor and verify an accurate zero setting. See “Calibration” on page 18 for
instructions on using a zero air calibration cylinder for setting the zero reading.
1. Verify that the sample-draw detector is sampling a fresh air environment (environment known
to be free of combustible gas).
2. Open the housing door.
3. Set a voltmeter to measure in the millivolt (mV) range.
4. Plug the voltmeter leads into the test points on the amplifier. Plug the positive lead into the red
(+) test point; plug the negative lead into the black (-) test point.
5. Verify a voltmeter reading of 100 mV (± 2 mV).
