VACUUM PRESSURE VALVE
Vacuum pressure valves protect the oil inside ester oil filled free-breathing transformers from constant exposure to the surrounding air.
The surrounding air contains oxygen which causes ester oil to degrade.
As the oil inside free-breathing transformers expand and contract due to heating & cooling, free air is continuously sucked into or pushed out of their tanks.
Vacuum pressure valves are installed in-line, between transformer tanks and silica-gel breather canisters. (see picture).
They only open momentarily to release pressure or vacuum conditions that develop inside transformer tanks but remain shut otherwise.
The VPV range of vacuum pressure valves are manufactured from long-lasting and durable parts and will provide many years of service, even in harsh outdoor conditions.