RKI Instruments 65-2497RK - Manual (Page 14)

10 • 65-2494RK/65-2497RK Oxygen Detector
Replacing the Oxygen Detector
NOTE: In most cases, it is only necessary to replace the plug-in sensor.
1. Turn off the controller.
2. Turn off or unplug incoming power to the controller.
3. If the detector is installed directly on a controller, open the controller door.
If the detector is installed remotely from a controller in a junction box, remove the
junction box cover.
4. If the detector is installed directly on a controller, disconnect the detector leads from
the detector terminal strip in the controller. Note the position of the color-coded leads
as you remove them.
If the detector is installed remotely from a controller in a junction box, disconnect the
detector leads from the terminal block in the junction box. Note the position of the
color-coded leads as you remove them.
5. Unscrew the detector from the controller conduit hub or junction box conduit hub.
6. Guide the detector leads of the replacement detector through the controller conduit
hub or junction box conduit hub, then screw the mounting threads of the detector into
the hub. If necessary for environmental conditions, apply thread sealant or teflon tape
to the hub and/or detector threads to seal them.
7. If the detector is installed directly on a controller, connect the detector leads to the
appropriate detector terminal strip terminals. See Figure 4 on page 5 for wiring to a
generic controller. See the controller operator’s manual and the controller’s detector
head specification sheet for the 65-2494RK detector for wiring specific to your
controller.
If the detector is installed remotely from a controller in a junction box, connect the
detector leads to the terminal block the same way the old detector was wired (see
Figure 4 on page 5). See the controller operator’s manual and the controller’s detector
head specification sheet for the 65-2497RK detector to verify the connections to the
controller are correct.
8. If the detector is installed remotely from a controller in a junction box, reinstall the
junction box cover.
9. Turn on or plug in power to the controller.
10. Turn on the controller and place into normal operation.
CAUTION: Allow the replacement detector to warm up for 5 minutes before you continue with
the next step.
11. Calibrate the replacement detector as described in “Calibration” on page 11.
Calibration Frequency
Although there is no particular calibration frequency that is correct for all applications, a
calibration frequency of every 3 months is adequate for most oxygen detector
applications. Unless experience in a particular application dictates otherwise, RKI
Instruments, Inc. recommends a calibration frequency of every 3 months for the oxygen
detector.