Rectifier Transformer

Have you checked the oil level alarm? You may be getting a false alarm reading.

aoa,

oil level is actually low because there is air cam and oil level deceased when we realized the air then level again full.actually the transformer built a air in oil level tank.

I am having a hard time understanding exactly what you are saying, but it sounds like you say you have a seal failure allowing air to enter the transformer and activate the alarm.

Have you checked the transformer seals?

Is this a brand new transformer or an old existing one, if new then it could be a transformer defect, if old then it could be a degraded seal allowing air in.

Your description of the problem is very confusing. Your description of the problem could mean that a valve was closed when it should have been open.

The first thing you should do is contact the manufacture. If the power supply is new, then it should be under warranty. Anything that you do could void the warranty.

Did you really change the oil? You should not have, this could void the warranty, and also the symptoms don't indicate it was necessary to do so. Also changing the oil incorrectly can seriously damage the transformer.