65-2483RK Multi Point Detector • 31
Calibration, O
2
Detector
This section describes how to calibrate the oxygen detector on the multi-point detector. It
includes procedures to prepare for calibration, set the fresh air reading, set the zero
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 the oxygen
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 oxygen detector.
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.
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 fresh air
reading.
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 peak hold feature for fresh air adjustment and a minimum
hold feature for zero adjustment. Because of this, the instructions call for turning
off the gas to a detector before making adjustments.
Setting the Fresh Air Reading
1.
Follow the directions in the controller operator’s manual for setting the fresh air
reading.
2.
When the instructions call for applying zero air to the detector, turn the regulator’s
on/off knob counterclockwise to open it. Gas will begin to flow.
3.
Allow the gas to flow for two minutes.
4.
Turn the regulator’s on/off knob clockwise to close it.
5.
Set the fresh air reading according to the controller operator’s manual.
6.
Unscrew the regulator from the zero air calibration cylinder. Leave the sample tubing