MD9832

Manual Call Point

The MD9832 is an automatic addressable Manual Call Point designed for use in wet areas, featuring IP66 protection. Activation is direct, requiring no tools or hammer; the operator triggers a fire alarm by deforming the front plate with a finger. Resetting is done with a specific tool. Activation closes a switch contact, processed by a circuit and sent to the microprocessor, which filters out transient signals. Communication with the Central Unit is via LCU or BCU control cards, providing 24Vdc power and modulating a serial transmission signal through the Loop using MD2 protocol.

The device address is set by the Central Unit. In case of a Central Unit fault, a Degraded Mode activates. An optical signal (red LED) flashes during an alarm. The enclosure is red thermoplastic, assembled with screws. The internal board is protected by conformal coating. A Test on Demand (TOD) feature checks the alarm activation circuit and LED functionality, providing consistent results as if manually performed. TOD enhances system reliability, allowing automatic tests with minimal effort.

TOD checks include:

1. Functionality of alarm activation circuit: Simulates button press, transmitting results to the control panel.
2. Functionality of Alarm LEDs: Detects LED failures, transmitting results to the control panel.

The Manual Call Point includes a short-circuit isolator to protect against short circuits. The isolator opens the loop connection when the current exceeds a set value, isolating the affected area and allowing the remaining branches to function. Two LEDs indicate the side with the short circuit. The isolator’s status is monitored and transmitted to the Control Unit, aiding in identifying activation points without accessing the terminal board.