Protect 3-Phase Electric Motors using the model 257 3-Phase Monitor which continuously monitors any three phase voltage system for abnormal conditions such as phase loss, low voltage or phase reversal.
This device is particularly helpful when monitoring three phase motor circuits. The unit, when properly adjusted, can detect and protect your three-phase electric motor from phase loss, low voltage, and phase reversal.
This device utilizes an electronic voltage and phase angle circuit to actuate an electro-mechanical 240V, 10A rated form C relay. The relay is set to respond within 50ms of the disturbance.
Once the abnormal condition has cleared and is brought back to normal conditions the device automatically resets and the motor can be re-started. For added motor protection, a manual reset device is optionally available.