Monitoring relays ensures reliable system protection against demage.

The relay has an adjustable off delay time range from 1s. to 6s. and an adjustable voltage asymmetry threshold from 30 to 70V. The relay is powered from L1 phase and does not protect from symmetric voltage drop. In case of detecting voltage asymmetry behind the executive contactor (at the V1, V2, V3 terminals) the relay will go off and disconnection and reconnection is required for restarting. After the powering is given system will switch the contactor’s circuit only in the absence of asymmetry and when the correct phase sequence is detected, regardless of the present, set time delay. If you don’t need to control contactor’s contacts, the V1, V2 and V3 inputs can be left and remain unconnected. Relay status is indicated by two LEDs.