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Description

System Sensor 2WT-B i3 Series Photoelectric Smoke Detector

Overview

The System Sensor 2WT-B is a photoelectric smoke detector in the i3 series, designed for 35VDC networked fire detection systems. This unit addresses the core installation problem in commercial and institutional environments: wiring complexity and maintenance access. The 2WT-B solves this through a plug-in detector head that seats onto a pre-wired base using Stop-Drop 'N Lock attachment—installers can rough-in bases during rough-in phase, then install detector heads during final trim-out. The photoelectric sensing chamber detects smoke particles in suspension, making it effective in environments where flame-based detection alone is insufficient.

Compatibility

The 2WT-B is compatible with System Sensor i3 series infrastructure, including mounting to standard 3½-inch octagonal back boxes, single-gang boxes, or direct drywall-anchor ceiling mounts. It integrates with networked fire panels and control systems that support i3 protocol signaling, including the 2W-MOD2 loop test/maintenance module and wireless SENS-RDR sensitivity reader for remote maintenance indication and obscuration measurement. The detector supports drift compensation and smoothing algorithms—these are built-in, not field-configurable—to reduce nuisance alarms in dusty or humid spaces.

Installation Notes

Mount the included base to a 3½-inch octagonal back box, single-gang box, or ceiling using drywall anchors. The large wire entry port and in-line terminals with SEMS screws allow neat internal routing. Detector dimensions (including base): 5.3 inches (127 mm) diameter × 2.0 inches (51 mm) height. Weight: 6.3 oz (178 g). Operating voltage: 35VDC. The removable detector cover and chamber simplify testing and maintenance. Built-in test switch allows local verification; wide-angle dual-color LED (red/green) provides instant visual status without removing the head.

What's in the Box

  • 1x 2WT-B photoelectric detector head
  • 1x mounting base (pre-wired ready)
  • 1x detector cover
Specifications
Product Type: Photoelectric Smoke Detector
Communication: i3 protocol (networked fire panel compatible)
Credential Type: NFC/13.56MHz
Voltage: 35VDC
Type: Photoelectric Smoke Detector with The...
Warranty: Manufacturer Warranty
Package Contents: d; Plug-in detector line, mounting base included
Analytics: Smoke Detection
Mount Type: Wall; Ceiling
Operating Temp: Range shall be 32°F–100°F (0°C–37.8°C). The 2WT-B Operating
Dimensions: (including base) 5.3 inches (127 mm) diameter; 2.0 inches (51 mm) height
Weight: 6.3 oz (178 g)
Mounting: 3½-inch octagonal back box
Operating System: Y2 Used to monitor the open position of an 1 in. to 12 in. 10 A @ 125/250 VAC; —
product_type: Reader
Operating_System: Y2 Used to monitor the open position of an 1 in. to 12 in. 10 A @ 125/250 VAC; —
Compatible With: networked
Product_Type: Photoelectric Smoke Detector
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System Sensor 2WT-B i3 Series Photoelectric Smoke Detector with The...

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