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  • No : 22343
  • Release Date : 2018/08/31 14:33
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Rating of a circuit breaker for transformers primary protection

How does the rated current of a circuit breaker which is located at the primary side of a transformer determine?
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When making a transformer to energize, a large inrush current may flow. The circuit breaker is therefore required to prevent unwanted trip.
The selection of the rated current of the circuit breaker shall satisfy both of the following conditions.
1. It shall be 1.1 times or more than the rated current of the transformer
2. Inrush current < Instantaneous tripping current of the circuit breaker
Product Name
Molded Case Circuit Breakers

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