System Sensor 2WTA-B

The System Sensor 2WTA-B 2-Wire Smoke Detector with Fixed Heat Sensor and Sounder is a great hardwired fire-protection solution that includes both smoke and heat detection. The smoke detector uses photoelectric technology, while the heat sensor activates at temperatures of 135°F or higher.

As part of the i3 Series lineup from System Sensor, the 2WTA-B offers superb functionality. Multiple smokes can be wired together in a parallel loop as Normally Open (NO) sensors, and their base plates share positive power. By doing this, a single smoke detector can close the circuit and cause all other smokes in the series to activate. An end of line resistor (EOLR) should be used to supervise the line.

Many systems have specific zones for 2-wire smoke detectors. In the case of the VISTA P-Series Systems, this is hardwired zone 1. The system automatically resets power to this zone after an alarm is cleared at the keypad. This eliminates the need for an auxiliary power supply, and it makes wiring easier in general. The 2-wire connection is relatively straightforward and simple, as one wire is for power, and the other is for data.

The 2WTA-B sounder is rated at 85 dB, which is fine for most residential applications. The sensor has a diameter of 5.3 inches and a thickness of 2 inches. It weighs a little more than 7 ounces. Mounting hardware comes included. A dual-color LED light assists with setup and general troubleshooting.

Read here to learn the difference between smoke detectors and smoke alarms. Photoelectric smoke detectors work with an alarm system, and when properly maintained and tested, can last for an indefinite period and do not automatically require replacement after a certain period of time like smoke alarms and CO detectors do.