BE1-25, Sync-Check Relay This relay monitors the voltages on both sides of a circuit breaker and determines that proper phase angle and voltage exist prior to allowing the breaker to be closed. Benefits Accurate, repeatable, and reliable operation. Minimized PT costs as a result of low sensing burden. Reduced battery load with low burden power supply. Simple HMI provides clear and intuitive settings for easy configuration without the use of a computer. Integrated voltage monitor provides complete supervision for conditions such as dead bus, where sync-check alone is not sufficient to supervise the breaker closing. LED indicators provide clear annunciation of status. Easily perform in-case system and device tests using test paddles.