Grounding protection and zero-sequence protection of circuit breakers
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Hello everyone. There is a device modification involved: originally, the main circuit breaker was a regular molded case circuit breaker, along with a Mitsubishi leakage circuit breaker of the NV-ZHA type, and a zero-sequence current transformer ZT100B was used to provide leakage protection. Is it possible to simply replace these components with a circuit breaker that already has grounding protection? For example, ABB’s Tmax T6N 800 PR222DS/P-LSIG R800 FF 3P. What is the difference between ground protection and zero-sequence protection in low-voltage circuit breakers?
Simply put, the zero-sequence current is the vector sum of IA, IB, and IC. The ground current is the vector sum of IA, IB, IC, and IN.