Monthly and 3 months checks for Transformer Maintenance

Monthly checkpoint

1) Check oil level in oil cap under silica gel breather. If it is found below the specified level, oil to be top up as per specified level.

2) Check breathing holes in silica gel breather & clean properly if required, for proper breathing action. 

3) Silica gel breather should be of blue colour. If colour is pink then replacement or heating of silica gel is required.

4) Check oil level in buchholz relay.

Checkpoint for interval of 3 months

1) Check for dirt deposition on bushings and tightness of its oil filling plug & examine for any crack in porcelain discs.

2) Check for BDV (>=60 KV) and PPM (<10 PPM)of transformer oil and tap changer oil.

3) Check for cooling fan manual and auto function. Lubricate fan bearings if required.

4) Check step by step mechanism operation & end position limit switches in On load/off load tap changer. Lubricate all bearing points.