16 • 65-2462RK Hydrogen Transmitter
NOTE:
When a transmitter is first powered up with a new amplifier, the initial output may be either
high or below zero depending on the setting of the zero pot. Be sure to make arrangements so
that this does not cause unwanted alarms.
9. Turn on power to the controller.
10. Turn on the controller and place it into normal operation.
11. Allow the transmitter to warmup for 5 minutes.
12. Calibrate the transmitter as described in “Calibration” on page 16 of this manual.
Calibration Frequency
Although there is no particular calibration frequency that is correct for all applications, a calibration
frequency of every 9 to 12 months is adequate for most hydrogen transmitter applications. Unless
experience in a particular application dictates otherwise, RKI Instruments, Inc. recommends a
calibration frequency of every 9 months.
If an application is not very demanding, for example detection in a clean, temperature controlled
environment where hydrogen is not normally present and calibration adjustments are minimal at
calibration, then a calibration frequency of every 12 months is adequate.
If an application is very demanding, for example if hydrogen is present often and in significant
concentrations or the environment is not well controlled, then more frequent calibration than every 9
months may be necessary. If potential catalyst poisons are known or likely to be present, more frequent
calibration than every 9 months will be necessary.
Calibration
This section describes how to calibrate the H
2
detector. It includes procedures to prepare for
calibration, zero with nitrogen, set the response reading, zero with background gas, and return to
normal operation.
NOTE:
This procedure describes calibration using a 0.5 LPM fixed flow regulator with an on/off
knob, a calibration cup for the detector, and a short piece of sample tubing to connect the
regulator to the calibration cup, a 100% N
2
cylinder, a 4% H
2
cylinder, and a zero air
calibration cylinder.
Preparing for Calibration
CAUTION:
This procedure may cause alarms at the controller. Take appropriate action to avoid this,
such as entering the calibration mode at the controller.
1. Screw the calibration cup onto the bottom of the detector.
2. Use the sample tubing to connect the regulator to the calibration cup.
3. Set a voltmeter to measure in the millivolt (mV) range.
