DI-B3

Siemens DI-B3 500-085081 Ionization Detector Air Duct | MXL Conventional Initiating Device/Base

The Cerberus Pyrotronics DI-3, DI-A3 and DI-B3 fire smoke detectors operate on the ionization principle. The detectors respond to the first traces of fire in the form of visible smoke or invisible products of combustion. The DI-3, DIA3 and DI-B3 have been developed for the wide range of commercial, industrial and institutional fire detection and extinguishing applications. The DI-3, DI-A3 and DI-B3 are approved in environments covered by UL 268 & UL 268A. The DI-B3 must be utilized with a Series 3 TM air duct housing.

The DI-3 Series detector is a plug-in, ionization detector and is designed for two wire system operation. The DI-3 is designed with adjustable sensitivity while the DI-A3 and the DI-B3 have a fixed sensitivity designed for their individual high air flow applications.

The DI-3, DI-A3 and DI-B3 consist of self-compensating dual ionization chambers and a highly stable solid state amplifier-switching circuit. One chamber detects the presence of combustion products, the second chamber serves as a reference, to stabilize the detector’s sensitivity for changes in environmental conditions. As products of combustion enter the sampling chamber, the chamber current is reduced producing a voltage change. At the time the voltage range exceeds the pre-determined threshold, an alarm is signaled to the control unit. The detector locks in upon alarm and must be reset from the control panel.

The sensitivity of the DI-3, DI-A3 and DI-B3 is preset at the factory. The electrical sensitivity can be monitored in the field using the Cerberus Pyrotronics sensitivity tester, test module TM-I3. The sensitivity test jack on the DI-3, DI-A3 and DI-B3 and the adjustment screw on the DI-3 are accessible from the front of the detector housing enabling the user to perform all sensitivity adjustments and tests without removing the detector from its base.

The detectors utilize a low profile surface mounting base, model DB-3S, which may be attached to either a 4" octagonal, single gang outlet box or 4" square wiring box — or the audible base model ADB-3, which must be attached to a 4" square, deep wiring box. The DB-3S base and ADB-3 audible base utilize screw-clamp terminals for all electrical connections, self-wiping contacts for reliability and contain provision for an optional concealed locking mechanism to prevent unauthorized removal of the detector head.

The DI-3 Series ionization detector has been designed to meet a wide range of system design parameters. The DI-3 detector is designed for open area protection in areas with air velocities up to 300 feet per minute.