The control module is easily de-mountable from the housing and connects to the sensor by means of a ten core screened / shielded cable. These terminations, together with supply and output contact connections are via two part screw terminals thus enabling installation of the housing and site cables prior to fittment of the module.The housing has a high level of ingress protection (IP67).
The unit incorporates a user programmable DIL switch to set the options which include detector sensitivity setting, auto/manual reset sequence selection, and one-shot/ coincidence voting for the alarm and trip/shutdown outputs.
The infra-red fire sensor air pressure and signal cable connections are fault monitored/fail safe. The unit also incorporates an auxiliary fault input which for example may be employed to integrate a "charger fault" from an associated Power Supply Unit. & common fault output contact.
The system's eight IR detectors are arranged in pairs within a four channel configuration. The DIL switch located at the top of the controller PCB permits the selection of system parameters related to the operation of these channels and their consequential outputs. (see following)

Alarm & Trip Outputs - Coincidence / Voting

The controller is equiped with two logic functions. One function operates when any channel registers a detection (1 out of 4). The other function operates on a voting principle which is activated when two coincident channel detections occur (2 out of 4). Two primary outputs are available - ALARM & TRIP Each of these having both a discrete LED indicator & output relay contact Poles 1 & 2 of the DIL switch permit selection of the operation of the output functions. Refer to table 1.
 

Latching / Auto Reset Selection

Both ALARM & TRIP outputs may be set for either Latching or Auto Reset operation. Poles 3 & 4 of the DIL switch permit selection of operation. Refer to table 2.
The time of delay before the Auto Reset occurs (when appropriate) may be set. When the option for latching only on coincident (2 out of 4) detection is selected then the Auto Reset delay is in effect the Scan Period within which a second channel must occur after first detection for a latched alarm to prevail.
Poles 5 & 6 of the DIL switch set the delay / scan period. Refer to Table 3.
 

Infrared Detection Sensitivity

The detection sensitivity may be set by means of DIL switch poles 7 & 8. There are four settings which are in effect 'trigger levels'. Refer to table 4 to the left and charts in Sensor Head specification sections.
 

Connections