65-2443 PPM Hydrogen Transmitter • 17
WARNING: A humidifier tube must be used when calibrating the ppm hydrogen transmitter for
the detector to respond properly to the calibration gas. Failure to use a humidifier
tube will result in an inaccurate calibration.
Preparing for Calibration
1. Screw the calibration cup onto the bottom of the hydrogen detector.
2. Use the humidifier tube to connect the regulator to the calibration cup.
3. Set a voltmeter to measure in the millivolt (mV) range.
4. Remove the junction box cover, then 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. Place the controller into its calibration mode or disable external alarms.
NOTE:
Calibrating the ppm hydrogen transmitter may cause alarms. Be sure to put the controller into
its calibration program or disable external alarms before continuing.
Setting the Zero Reading
The detector’s zero setting is controlled by electronics and is not user-adjustable.
Setting the Span Reading
1. Screw the regulator into the 2,000 ppm H
2
calibration cylinder.
2. Turn the regulator knob counterclockwise to open the regulator.
3. Allow the calibration gas to flow for 2 minutes.
4. Verify a reading of 500 mV (±2 mV) on the voltmeter. If necessary, use the span pot on the
amplifier to adjust the reading.
5. Turn the regulator knob clockwise to close the regulator.
6. Unscrew the regulator from the 2,000 ppm H
2
calibration cylinder.
Setting the Linearization
1. Screw the regulator into the 1,000 ppm H
2
calibration cylinder.
2. Turn the regulator knob counterclockwise to open the regulator.
3. Allow the calibration gas to flow for 2 minutes.
4. Verify a reading of 300 mV (±2 mV) on the voltmeter. If necessary, use the linear pot on the
amplifier to adjust the reading.
5. Turn the regulator knob clockwise to close the regulator.
6. Unscrew the regulator from the 1,000 ppm H
2
calibration cylinder.
