3 phase over/under voltage relay M3US

Control relay for monitoring 3-phase networks without neutral. Adjustable switch at the front for adjustment of correct voltage in 3-phase networks. The switch's position is not registered until the operating voltage is switched on. If the switch position is changed during operation, all LEDs (LED indications) begin to flash but the unit will continue to function normally with the voltage that was set at the most recent power connection. Monitors under-voltage between the phases that can be set between -2 % and -20 % of Un (measurement voltage) and over-voltage that can be set between 2 % and 20 % of Un. Time delay Tt prevents relay change-over in the event of temporary disturbances and is adjustable between 0.3-30 s. Green LED (Un) indicates supply voltage OK. Yellow LED (R) indicates active relay output.