About leakage circuit breaker!Thanks!!!

The disadvantage of using a leakage circuit breaker that covers the entire electrical installation in a flat :
- They do not allow a system to be easily split into multiple sections with independent fault protection, due to the fact that earthing systems are usually bonded to things like pipework.
- They may be tripped by external voltages on something connected to the earthing system such as metal pipes.
- They introduce additional resistance and an additional point of failure into the earthing system.
- They cannot detect earth faults that do not go through the earthing system.

2007-08-22 00:10:54 補充：
A leakage circuit breaker is installed covering the entire electrical installation in a property is considered bad practice because any fault will cause all power to be cut to the premises including to devices (eg lights) and injury may be caused by occupants being suddenly plunged into darkness.

2007-08-22 00:11:24 補充：
Normal practice in domestic installations is to use a leakage circuit breaker for all protected circuits but to have some circuits that are not protected at all (sockets usually are on the leakage circuit breaker, lights usually aren't other circuits vary by who installed the system).