65-2462RK Hydrogen Transmitter • 17
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. Use the following formula to determine the correct test points output for the calibrating sample.
Output (mV) = (calibrating sample/fullscale) X 400 + 100
For example, with a calibrating sample of 4% volume H
2
and a fullscale setting of 10% volume,
the correct output for the H
2
test points is 260 mV.
260 (mV) = (4/10) X 400 +100
Zeroing with Nitrogen
NOTE:
If you can verify a fresh air environment, it is not necessary to use the zero air calibration
cylinder to set the zero reading.
1. Screw the regulator into the 100% N
2
calibration cylinder.
2. Turn the regulator knob counterclockwise to open the regulator.
3. Allow the gas to flow for one minute.
4. Verify a voltmeter reading of 100 mV ± 2 mV at the H
2
test points as described in the Preparing for
Calibration section above.
5. If necessary, use a small flat-blade screwdriver to adjust the zero pot for the H
2
channel until the
voltmeter reading is 100 mV ± 2 mV.
6. Turn the regulator knob clockwise to close the regulator.
7. Unscrew the regulator from the calibration cylinder. Leave the sample tubing connected to the
regulator and the calibration cup.
Setting the Response Reading
1. Screw the regulator into a 4% H
2
calibration cylinder.
2. Turn the regulator knob counterclockwise to open the regulator.
3. Allow the calibration gas to flow for one minute.
4. Check the mV output on the H
2
transmitter test points and verify that the reading matches the
response reading (±2 mV) you determined earlier.
5. If necessary, use the span pot on the H
2
transmitter to adjust the reading to match the correct
response reading.
6. Turn the regulator knob clockwise to close the regulator.
7. Unscrew the regulator from the calibration cylinder. Leave the sample tubing connected to the
regulator and the calibration cup.
