16 • 65-2424RK H
2
S Transmitter
Setting the Zero Reading
NOTE:
If you can verify that the H
2
S transmitter is in a fresh air environment, you do not
need to apply zero air to the detector before adjusting the zero reading.
1. Turn the regulator on/off knob counterclockwise to open it.
2. Hold the calibration cup against the H
2
S sensor’s face. Leave the rubber boot and sealing
spacer on the sensor when calibrating. Hold the cup on gently to allow gas to escape and
avoid pressurizing the sensor’s sensing face.
3. Allow the gas to flow for 2 minutes.
4. Verify a reading of 100 mV (± 2mV).
5. If necessary, use the zero pot on the amplifier PCB to adjust the reading to 100 mV (±
2mV).
6. Turn the regulator on/off knob clockwise to close it.
7. Remove the calibration cup from the sensor face.
8. Unscrew the regulator from the zero air calibration cylinder.
Leave the sample tubing connected to the regulator and the calibration cup.
Setting the Response Reading
1. Verify that the calibration gas is representative of the transmitter’s target gas.
2. For toxic gas cylinders (like H
2
S), it is important to vent the regulator while installing it
onto the cylinder. Venting the regulator during installation helps prevent air from getting
into the cylinder and degrading the gas. Open the regulator by turning the knob
counterclockwise and then install it onto the cylinder.
3. Hold the calibration cup against the H
2
S sensor’s face. Leave the rubber boot and sealing
spacer on the sensor when calibrating. Hold the cup on gently to allow gas to escape and
avoid pressurizing the sensor’s sensing face.
4. Allow the gas to flow for 2 minutes.
5. Verify that the reading matches the response reading (± 2mV) you determined earlier.
6. If necessary, use the span pot on the amplifier PCB to adjust the reading to match the
correct response reading.
7. Turn the regulator on/off knob clockwise to close it.
8. Remove the calibration cup from the sensor face.
9. Unscrew the regulator from the calibration cylinder.
NOTE:
For convenience, leave the components of the calibration kit connected by the sample
tubing.
