System Sensor B112LP

The System Sensor B112LP is a wired plug-in smoke detector base unit compatible with the System Sensor 1151 (Ionization) and 2151 (Photoelectric) smoke detector heads. The base unit requires a 4-wire connection: two for power and two for data back to your alarm or fire control panel. This particular base unit requires 24 volts so you will need a 24 VDC power supply to power the 1151 or 2151 smoke/heat detectors. The base diameter is 6.2 inches and approximately 1 inch in depth. There are two integrated relays: Form A and Form C. This means you can choose between using a normally open (NO) or normally closed (NC) configuration.

It is always recommended to supervise life safety devices. This can be accomplished by wiring an end of line (EOL) resistor to the last smoke in the circuit. The resistance value will depend on the control panel. The most common Honeywell VISTA panels require a 2K ohm resistor for end of line supervision. This protects the smokes from line cuts or any damage that compromises the data connection back to the panel. In the event of a wiring issue or sever the system will report a fire trouble. This will trigger an alert on the keypads locally and result in a phone call from the central station assuming the system is monitored.