System Sensor 2WTA-B Two Wire Smoke Detector With Built-In Heat Sensor

The System Sensor 2WTA-B is a two wire smoke detector that features a built-in 135 degree heat detector as well as an on-board sounder. The sounder provides an 85 dB warning tone to let those in the area know a fire emergency is occurring. The heat detector in this unit will trip if the temperature reaches 135 degrees.

The 2WTA-B features drift compensation to help reduce false alarms by reducing false trips due to dust and other particulates. It also uses smoothing algorithms to help cut RF interference and further reduce false alarms. The smokes operate on either the 12V or 24V power structure. The 2WTA-B measures in at 5.3 in. in diameter and is 2 in. high. 

Most  people wonder what the difference is between two wire and four wire smokes. Here are a few things that differentiate them:

• The amount of wires each use. 2 wire smokes use the same two wires for power and for triggering an alarm. Four wire smokes have 2 wires for power and then separate 2 wires for triggering an alarm.
• Either the 2 wire or 4 wire smokes hook into the alarm panel.

2 wire smokes have to all run on the same loop while 4 wire smokes can be zoned out to designate different areas where they are installed. This lets you know where the fire originated. With 2 wire smokes you'll just know that there is a fire somewhere in the building.