RKI Instruments 65-2481RK - Manual (Page 27)

65-2481RK Multi Point Detector • 23
applications. Unless experience in a particular application dictates otherwise, RKI
Instruments, Inc. recommends a calibration frequency of every 3 months for the catalytic
LEL, oxygen, H
2
S, and CO detectors and every 6 months for the infrared LEL detector.
If an application is not very demanding, for example detection in a clean, temperature
controlled environment, and calibration adjustments are minimal at calibration, then a
calibration frequency of every 6 months is adequate for the catalytic LEL, oxygen, H
2
S,
and CO detectors and every 9 to 12 months is adequate for the infrared LEL detector.
If an application is very demanding, for example if the environment is not well controlled,
then more frequent calibration than every 3 months for the catalytic LEL, oxygen, H
2
S,
and CO detectors and every 6 months for the infrared LEL detector may be necessary.
Calibration, LEL, H
2
S, and CO Detectors
This section describes how to calibrate the LEL, H
2
S, and CO detectors on the multi-point
detector. It includes procedures to prepare for calibration, set the zero reading, set the
response reading, and return to normal operation. It describes calibration using a
calibration kit that includes a calibration cup, calibration gas, sample tubing, and a fixed
flow regulator with an on/off knob. RKI Instruments, Inc. recommends using a 0.5 LPM
(liters per minute) fixed flow regulator. To properly calibrate the multi-point detector, you
must calibrate each connected detector. Perform the following procedure for each
connected LEL, H
2
S, or CO detector.
WARNING: The controller is not an active gas monitoring device during the calibration
procedure.
Preparing for Calibration
WARNING: Do not remove the junction box cover or detector housing cap while the
circuits are energized unless the area is determined to be non-hazardous.
Keep the junction box cover and detector housing cap tightly closed during
operation.
1. Screw the calibration cup onto the bottom of the detector you wish to calibrate.
NOTE If you can verify that the multi-point detector is in a fresh air environment, you
do not need to apply zero air to the detector before adjusting the zero reading.
2. Screw the regulator into the zero air calibration cylinder. Make sure the regulator is
off. It is off when the on/off knob is turned all the way clockwise.
3. Use the calibration kit sample tubing to connect the fixed flow regulator to the
calibration cup.
4. Put the controller into its calibration program. See the controller operator’s manual
for instructions to enter the calibration program.
NOTE: RKI controllers have a minimum hold feature for zero adjustment and a peak
hold feature for span adjustment. Because of this, the instructions call for turning
off the gas to a detector before making adjustments.