Function of the pressure relief valve

The role of transformer pressure relief valve is mainly as follows:

to protect the transformer tank safety: the pressure relief valve can be opened when the pressure inside the tank reaches a certain value (usually set at 55kPa or so), and the expanded transformer oil is released to the external oil locker or other safe containers, so as to avoid the tank rupture due to the high pressure.

Reflect transformer internal faults: when the transformer internal turn-to-turn short-circuit or core multi-point grounding and other faults, it will produce localized overheating, which will cause the oil volume to expand, and the pressure release valve will open. Operation and maintenance personnel can through the action of the pressure release valve to initially determine the transformer internal problems, timely inspection and repair of the transformer, to prevent further expansion of the fault.

Maintain the pressure balance inside the transformer: so that the pressure inside the transformer can change in a relatively stable range, to avoid the pressure fluctuation is too large to affect the performance and life of the transformer.