4-wire conventional smoke detectors use separate power and alarm circuits allowing detectors to be reset from the panel without cutting power, used in commercial fire detection systems with control panels.
| Pin | Name | Function | Type |
|---|---|---|---|
| 1 | PWR+ | Detector power positive | PWR |
| 2 | PWR- | Detector power negative | GND |
| 3 | ALARM+ | Alarm circuit positive | I/O |
| 4 | ALARM- | Alarm circuit negative | I/O |
4-wire conventional smoke detectors use separate power and alarm circuits allowing detectors to be reset from the panel without cutting power, used in commercial fire detection systems with control panels.