Sinopower Transformer (Changzhou) Co. Ltd's box type transformer is fully sealed, fully insulated, compact in structure, aesthetically pleasing in appearance, and only about one-third the size of a box type substation (European box type transformer). Disconnect the circuit breaker on the high-voltage side of the maintenance transformer, close the grounding switch, fully discharge the transformer, lock the high-voltage cabinet, and hang a "Do Not Close" sign at the switch handle.

Clean the dust around and on the accessories of the box type transformer, check whether the fire-fighting facilities and ventilation system are in good condition, use aluminum zinc coated steel plates, and use standard container materials and manufacturing processes for the frame.