Circuit breaker normally used by the utility company are for high voltage (HV) 11KV and above. HV circuit breaker is important to avoid damage to expensive switchgears and large area interruption. Low voltage circuit breaker available on the market normally use by commercial consumer and it operate based on three phase tripping.

For LV system (3 phase 4 line), circuit breaker are being neglected due to its expensive cost and hardly available. There is no high current rating three phase circuit breaker with single pole tripping available on the market. A single pole circuit breaker with 400A rating can be used to optimize the LV distribution systems.

Unlike the HV circuit breaker that normally has an autorecloser function, low voltage system only consist of fuse for protection of over current. The utility company will have to dispatch their personnel each time a fuse blew. Interruption on low voltage supply can only be known when consumer called in. Every time a fuse blew long interruption duration experienced due to complain processing and traveling time taken by the technician to replace the blown fuse. Danger of electrocution also expose to the utility technician when they replace a blown fuse on live line.


Replacing blown fuse on live line