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Moeller NZM MCCB molded case circuit breaker accuracy tripping tolerance band

The tolerance for tripping accuracy in Moeller NZM molded case circuit breakers (MCCBs) is +/- 20%.  Many Moeller NZM circuit breaker time current curves depict circuit breaker operation as a single (bell-shaped) trip curve line, and do not represent breaker operation with a minimum/maximum tolerance band drawn on the respective time current curve.

Reference section 11, page 12, attached "white paper" document, which discusses Moeller NZM circuit breaker selectivity and discrimination.

  1. Moeller NZM_MCCB selectivity-discrimination_WP038002EN_1-2014.pdf