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What is the guideline for selecting the over current protection (OCP) for an autotransformer connection?

Reference the National Electrical Code (NEC) Article 450-4 for autotransformers. This allows the primary OCP to be rated no more than 125% of the autotransformer connection`s primary full load current rounded up to the next standard rating per NEC Article 240-6(a).

CTA-ID : 2004062
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