System Sensor 4WT-B

4-Wire Smoke Detector with 135°F Fixed Heat Sensor

System sensor 4wt b 4 wire smoke detector with fixed heat sensor

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The System Sensor 4WT-B is a 4-wire photoelectric smoke detector that also includes a built in 135°F fixed temperature heat sensor. The sensor offers reliable and consistent fire detection for virtually any home or business. Buy the system sensor 4WT-B 4-Wire Smoke from Alarm Grid.
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The System Sensor 4WT-B 4-Wire Smoke Detector with 135°F Fixed Heat Sensor provides reliable fire-protection for residential and commercial locations. The sensor uses a 4-wire configuration and photoelectric technology to detect smoke, while the heat sensor provides added reliability.

As a 4-wire smoke detector, various add-ons are needed to integrate the 4WT-B with an alarm system. You will need an external power relay to drop power to the device once the fire alarm has been cleared. You might also need an external power supply if the panel does not supply sufficient power. An end of line resistor (EOLR) and an end of line power supervision relay are also needed.

The advantage to using a 4-wire smoke is that they can usually be set up with any regular hardwired zone, provided that the right equipment is used. This is not the case with 2-wire smokes, which require special resetting features and addtional current from the zone. However, 2-wire smokes are generally easier to set up, and they are better-suited for DIY users.

As a smoke and heat sensor, the 4WT-B works very reliably using photoelectric technology. This involves using an internal light that becomes refracted when smoke enters the chamber. The 135°F fixed temperature sensor ensures greater consistency in detecting fires. The sensor can also be used for freeze detection, which activates at fixed temperatures of 41°F and lower. The sensor measures 5.3" in diameter, and it has a height of 2.0".


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