CTP21 control units for 3 remote sensors

Control unit wall installation for 3 sensors.
It can receive 1, 2, or 3 sensors. It is equipped with 2 gas detection thresholds and activates 2 relays when the corresponding alarm thresholds are exceeded, plus 1 fault relay.
The gas concentration is displayed using bar graphs.
The second threshold is intentionally delayed by 30 seconds upon activation to prevent false alarms caused by a temporary presence of gas (purging).

This control unit is also equipped with a “TEST” button, which allows verification of the system’s operation, and a “RESET” button, which resets the relay of the second threshold, which is latched.

Note: The “TEST” button does not check the calibration of the sensors, but only verifies the electrical operation of the system.

Any faults are indicated by the yellow LED and transmitted via relay.