How To Prevent Low-voltage Pole-mounted Circuit Breakers From Tripping Beyond Their Rated Circuit Breaker?

Adopting a reasonable protection setting scheme can reduce the possibility of cascading tripping of Lv Pole Mounted Circuit Breakers. Over-level tripping refers to a situation where, when a fault occurs at a lower level, the circuit breaker should trip first, but due to various reasons, the circuit breaker at the higher level trips instead, causing the power outage area to expand and affect adjacent lines.

The circuit breaker's setting current and operating time should be matched with system requirements and set according to the principle of decreasing from the main line to the branches. In this way, when an overcurrent or short circuit occurs in a local branch, the nearest circuit breaker can disconnect first, thus avoiding cascading tripping by the upper-level circuit breaker.