65-2670-XX-04 M2A Transmitter Operator’s Manual
11
Detector Housing Body
The detector housing body protects the electronic components within the housing. Use the mounting
threads at the top of the housing to screw the detector into the 3/4 NPT hub on the bottom of the
detector junction box. Two wires extend from the top of the detector housing body. Use these wires to
connect the detector to the terminal strip. One of the wires is color-coded for each detector type.
The housing includes a four-socket pattern. This socket pattern accepts the sensor’s four pins to secure
the sensor within the detector housing. A pre-amplifier, located between the sockets and two
interconnect wires, conditions the sensor’s signal before the signal reaches the controller.
Housing Cap & Cap Gasket
The housing cap screws onto the detector housing. An adhesive backed gasket inside the detector
housing cap helps ensure that the sensor remains plugged into the detector housing body.It retains the
plug-in sensor and protects it from damage. Unscrew the detector cap to access the plug-in sensor for
maintenance or replacement. A cap gasket seals the interface between the housing and cap.
Plug-In Sensor
The sensor is secured within the detector assembly by the housing cap. Through a series of chemical
and electrical reactions, the sensor produces an electrical output that corresponds to the detection range
of the transmitter.
Calibration Adapter/Splash Guard
A calibration adapter/splash guard is installed on the detector. A fitting at the bottom of the calibration
adapter/splash guard allows a length of tubing to be connected for calibration and routed to a more
easily accessible location (near the M2A junction box is optimal for ease of calibration). The
calibration adapter/splash guard also protects the detector from splashing water or direct water spray.
Magnetic Wand
The magnetic wand is a short plastic rod with a magnet in one end. It is used to actuate the magnetic
control switches on the control PCB while the junction box cover is still installed so that non-intrusive
calibration can be performed.
Hydrophobic Membrane
Plug-in Sensor
Detector
Housing Cap
Cap Gasket
Detector Housing Body
(different for each detector type)
Figure 2: Detector Component Location
