RKI Instruments 35-3010RK-04 - Manual (Page 19)

35-3010RK-04 Sample-Draw Detector • 15
Detector” on page 9 describes detector wiring connections.
4. Calibrate the problem channel or channels as described in the Calibration section of
this manual.
5. If the fail condition continues, replace the sensor from the problem channel or
channels as described later in this section.
6. If the fail condition continues, contact RKI Instruments, Inc. for further instruction.
Slow or No Response/Difficult or Unable to Calibrate
Symptoms
• One or more of the sensors respond slowly or do not respond during the monthly
response test.
• Unable to accurately set the zero or response reading on one or more of the channels
during the calibration procedure.
• One or more of the sensors requires frequent calibration.
NOTE: Under “normal” circumstances, the sample draw detector requires calibration
once a quarter. Some applications may require a more frequent calibration
schedule.
Probable Causes
• The calibration cylinder is low, out-dated, or defective.
• 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.
Recommended Action
1. Verify that the calibration cylinder contains an adequate supply of a fresh test sample.
2. If necessary, set the correct flow rate with the bypass valve or flow adjust
potentiometer.
3. If you cannot set the correct flow rate, check the sample line for obstructions or kinks.
4. If the calibration/response difficulties continue, replace the sensor as described later
in this section.
5. If the calibration/response difficulties continue, contact RKI Instruments, Inc. for
further instruction.
Replacing Components of the Sample Draw Detector
This section includes procedures to replace the sensors, the hydrophobic filter, and the
charcoal filter.
Replacing the Combustible Sensor
1. Turn off incoming power.
2. Open the housing door of the sample draw detector.
3. Unscrew and remove the two screws that secure the retaining plate, then lift the plate,
connector, and sensor out of the housing.
4. Unplug the connector from the sensor.
5. Verify that you are using the correct replacement sensor (NC-6245 is printed on the
sensor), then plug the sensor into the connector.