RKI Instruments 65-2619RK-CH4-4 - Manual (Page 8)

3 65-2619RK-CH4-4 M2 Transmitter Operator’s Manual
Chapter 2: Description
Overview
The M2 combustible gas transmitter utilizes an infrared type of detector which has some
advantages over a catalytic type of combustible detector. The infrared detector will
generally have a longer service life than a catalytic detector, it will require calibration less
often, and it can detect combustible gas even if there is no oxygen in the sample which
allows detection of combustible gas in an inert atmosphere.
This chapter describes the components of the M2 transmitter. The transmitter is a 4 - 20
mA type detector head. It consists of the combustible gas detector, calibration adapter/
splash guard, terminal PCB, the M2 junction box, and the detector junction box. The two
junction box configuration is intended for situations where the detector needs to be
installed at an inaccessible location. The detector junction box can be installed at the
inaccessible location and the M2 junction box can be installed in a more readily accessible
area.
External Description
This section describes the junction boxes and all external components of the M2
transmitter.
Figure 1: M2 External Components
3/4" NPT Conduit Hub
Terminal
Strip
Magnetic
W and
Detector
Junction Box
3/4" NPT C onduit Hub
Calibration Adapter/
Splash G uard
IR LEL Detector
Mounting Slot (2x)
W indow
M2 Junction Box