RKI Instruments 65-2512RK - Manual (Page 6)

2 • 65-2511RK/65-2512RK Oxygen Detector
Description
This section describes the oxygen detector and the junction box.
Oxygen Detector
The detector’s sensing element along with signal conditioning components are
encapsulated within a conduit mounting black anodized aluminum housing. The sensing
element used is a capillary type that is not susceptible to output changes with changes in
atmospheric pressure.Through a series of chemical and electronic reactions, the detector
produces a millivolt output that is proportional to the detection range. 3/4” NPT
mounting threads at the top of the detector allow you to mount the detector to the
junction box or a 3/4” NPT conduit fitting. Two color-coded leads extend from the top of
the detector. The leads allow you to connect the detector to a controller.
Junction Box
The junction box allows you to install the oxygen detector at a mounting site that is
remote from a controller, and it protects the detector wiring connections. Two conduit
hubs allow you to mount the oxygen detector to the junction box and connect the wiring
from the detector to a controller. Three spacers installed on the back of the junction box
control the distance of the junction box from a mounting surface and ensure that there is
enough room to install a calibration cup on the detector during calibration.
A terminal block within the junction box facilitates the wiring process. A cover on the
front of the junction box allows access to the interior of the junction box.
Installation
This section describes procedures to mount the oxygen detector in the monitoring
environment and wire the detector to a controller.
Mounting the Oxygen Detector
NOTE: If you are mounting a 65-2511RK, it does not include a junction box and is
usually factory installed in one of a controller’s conduit hubs or may be field
installed using the 3/4” NPT threads on the end with the wires. The 65-2512RK
includes a junction box as shown in Figure 1 below.
1. Select a mounting site that is representative of the monitoring environment. Consider
the following when you select the mounting site.
• Select a site where the detector is not likely to be bumped or disturbed. Make sure
there is sufficient room to perform start-up, maintenance, and calibration
procedures.
• Select a site that is at normal breathing level.