RKI Instruments 65-2498RK - Manual (Page 14)

65-2495RK/65-2498RK H
2
S Detector • 14
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 8 for wiring to a
generic controller. See the controller operator’s manual and the controller’s detector
head specification sheet for the 65-2495RK 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 8). See the controller operator’s manual and the controller’s detector
head specification sheet for the 65-2498RK 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.
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 14.
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 H
2
S detector applications.
Unless experience in a particular application dictates otherwise, RKI Instruments, Inc.
recommends a calibration frequency of every 3 months for the H
2
S detector.
If an application is not very demanding, for example detection in a clean, temperature
controlled environment where H
2
S is not normally present, and calibration adjustments
are minimal at calibration, then a calibration frequency of every 6 months is adequate.
If an application is very demanding, for example if the environment is not well controlled
or if H
2
S is often present, then more frequent calibration than every 3 months may be
necessary.
Calibration
This section describes how to calibrate the H
2
S detector. It includes procedures to prepare
for calibration, set the fresh air 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.