A PT cabinet, which stands for Potential Transformer cabinet, is typically used to house voltage transformers connected to the busbar for measurement and protection purposes. In electric power distribution, a busbar (also bus bar) is a metallic strip or bar, typically housed inside switchgear, panel boards, and busway enclosures for local high current power distribution, transmission, or switching substations. i mean if pt is not in operation position you can not close the circuit breaker. The circuit breaker's fuse provides protection for the voltage. What is a bus bar? In Simple words, a bus-bar is a common connection point or a node for multiple incoming and outgoing circuits such as power lines or feeders. Busbars can come in various shapes and sizes and are constructed of copper, aluminum.
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