System Sensor D4P120 Duct Detector Power Board

Overview

The D4P120 is a 29VDC power distribution board designed as a component within System Sensor duct smoke detector assemblies. This rectangular module (14.38 in × 5 in × 2.5 in) supplies regulated power and signal routing to photoelectric sensor heads in fire detection systems. Deploy this board when integrating D4120 or compatible InnovairFlex duct detectors into a fire alarm control panel — it handles the power conditioning and terminal connections that keep the detector head isolated and operational across a range of duct airflow conditions.

Compatibility

The D4P120 works with System Sensor InnovairFlex D4120 duct smoke detectors (both red and white housing variants). The power board supports 4-wire photoelectric sensor configurations and can monitor multiple sensor heads — the D4120's design allows the power board to supervise a D4S sensor simultaneously (supply and return side sensing). Compatible with fire alarm control architectures that accept 29VDC-powered duct detector modules with standard terminal-block wiring.

Installation Notes

Mount the D4P120 horizontally or vertically within the detector housing or adjacent control enclosure. The board includes a ¾-inch conduit knockout for field wiring entry and ample terminal space for 4-wire connections. Operating temperature range is –4°F to 158°F; humidity must stay below 95 percent non-condensing. Built-in short-circuit protection prevents damage during installation or commissioning. Wiring terminals are high-contrast labeled to reduce connection errors. A Test/Reset button on the module allows field verification of power and sensor continuity during startup.