Power supply is 3x400/440V 50/60Hz. The unit will start together with the pump(if no additional protection with a starting time delay is provided from pump control). After reaching the determined pressure the unit will stop. Should the pump delivery pressure drop during operation, the unit will start again for re-evacuation. The compact design is especially for lower capacity pumps like emergency fire pumps or other pumps where no compressed air is available. The unit will start together with the pump(if no additional protection with a starting time delay is proviede from pump control). After reaching the determined pressure the unit will stop. Should the pump delivery pressure drop during operation, the unit will start again for re-evacuation.