Distribution transformer refers to a static electrical appliance that transforms AC voltage and current according to the law of electromagnetic induction in the power distribution system. Distribution transformers should be installed on poles or on the ground in the open air.   

Oil-immersed distribution transformers can be divided into main body, oil conservator, insulating sleeve, tap switch, protection device, etc.

Oil-immersed transformers are divided into :

1. Unsealed type oil immersed transformer
2. Sealed type oil immersed transformer
3. Sealed oil-immersed transformer