System Sensor 4WTA-B i3 4-Wire Smoke and Heat Detector with Sounder

The System Sensor 4WTA-B combines smoke, fixed-temperature heat, freeze monitoring, and local audible warning in a conventional four-wire detector. Separate power and alarm paths make it appropriate only for panels and circuits designed to supervise and reset four-wire fire devices.

Its photoelectric chamber uses drift compensation and smoothing to maintain useful sensitivity as environmental conditions change. A restorable 135 F thermal element adds heat response, the red LED identifies a freeze-trouble condition below 41 F, and the built-in horn produces an 85 dBA temporal-three pattern during alarm.

When a system requires multiple i3 sounders to operate together, a compatible reversing and synchronization module is part of the design rather than an optional afterthought.

Test detector power, alarm contacts, end-of-line supervision, synchronized output, panel reset, and monitoring transmission together. This keeps the installation understandable for the customer and serviceable later.