Secutron MRI-B501 Smoke Detector Base

The Secutron MRI-B501 comes with plug-in detector bases intended for use in an intelligent system with screw terminals provided for power (+ and –), and remote annunciator connections. Communication takes place over the power lines.

In fact, this Secutron MRI-B501 detector base mounts directly to 4″ square with plaster ring, 31/2″ octagon, 50 mm, 60 mm, and 70 mm centers. All wiring must be installed in compliance with all applicable local codes and any special requirements of the local authority having jurisdiction. Also, proper wire gauges should be used. The conductors used to connect smoke detectors to control panels and accessory devices should be color-coded to reduce the likelihood of wiring errors. Besides, improper connections can prevent a system from responding properly in the event of a fire.

For signal wiring (the wiring between interconnected detectors and modules), it is recommended that the wiring be no smaller than 18 AWG (0.823 mm²). Furthermore, alarm system control panels have specifications for allowable loop resistance. Consult the control panel specifications for the total loop resistance allowed before wiring the detector loops. Make wiring connections by stripping about 3/8″ (10 mm) of insulation from the wire end (use strip gauge molded-in base). Then slide the wire under the clamping plate and tighten the clamping plate screw. Do not loop the wire under the clamping plate.

Features / Specifications

• Base Diameter: 4.0″ (10.2 cm)
• Base Height: 0.74″ (18.8 mm)
• Operating Voltage: 15 to 32 VDC
• Standby Current: 150 µA
• Listings: UL268, ULC S529