RKI Instruments 35-3001A-01-02 User Manual
Page 18
14 • 35-3001A-01-02 Combustible Gas Sample-Draw Detector
4.
Use the following formula to determine the correct test points output for the test sample.
Output (mV) = (calibrating sample/fullscale) X 400 + 100
For example, with a test sample of 50 %LEL and a fullscale setting of 100 %LEL, the correct
output is 300 mV.
300 (mV) = (50/100) X 400 +100
Performing the response test
1.
Screw the demand flow regulator into the calibration cylinder.
2.
Connect the calibration tubing from the demand flow regulator to the inlet fitting. Gas will
begin to flow.
3.
After approximately one minute, verify that the reading at the controller stabilizes within
± 20% of the concentration of the test sample. If the reading is not within ± 20% of the test
sample, calibrate the sample-draw detector as described in “Calibration” on page 18.
4.
Remove the calibration tubing from the inlet fitting, then reconnect the sample tubing to the
inlet fitting.
5.
Remove the voltmeter leads from the amplifier test points.
6.
Close the housing door.
7.
Store the calibration kit in a safe place.
Biannual Calibration
Calibrate the sample-draw detector as described in “Calibration” on page 18.
Troubleshooting
The troubleshooting guide describes symptoms, probable causes, and recommended action for
problems you may encounter with the sample-draw detector.
NOTE: This troubleshooting guide describes sample-draw detector problems only. See the
controller Operator’s Manual if the controller exhibits any problems.
Fail Condition
Symptoms
•
The sample-draw detector’s Fail LED is on.
•
The monitoring device is operating properly but indicates a reading well below zero or a
failure alarm.
Probable causes
•
The sample-draw detector’s flow rate is too low because of an obstructed sample line, failed
pump, etc.
•
The sample-draw detector is malfunctioning.
•
The sensor and/or amplifier wiring is disconnected or misconnected.
Recommended action
1.
At the sample-draw detector, set the correct flow rate with the sensor flow control valve.
2.
If you cannot set the correct flow rate, check the sample lines for obstructions or kinks.
3.
Verify that the sensor wiring and amplifier wiring is correct and secure. “Wiring the
Combustible Gas Sample-Draw Detector to a Controller” on page 10 describes sensor and
amplifier wiring connections.