Medium/low voltage polyphase transformer protecting device for transformer substation, has cover made of insulating material to encase fuses, connection units and parts, immersed in insulation oil tank, of plug-in cross-arms of transformer

摘要

The device has a cover (13) made of insulating material to encase an upstream part of medium voltage fuses (7), connection units (6) and parts (5), immersed in a tank (2) containing insulation oil, of medium voltage plug-in cross-arms (4) of a medium/low polyphase transformer. The cross-arms and the fuses respectively include insulating bodies (14, 15). Slots are arranged on the bodies of the cross-arms and fuses before the encasing operation. An independent claim is also included for a method for manufacturing a cover of a medium/low voltage polyphase transformer protecting device.