Application of quadrupole circuit breaker, the current domestic is not required to use the provisions of mandatory national standards or rules such as, although regional electric quadrupole (circuit breaker) design specifications have been introduced, but the installation and installation of electrical quadrupole debate is still in use, some areas appear the trend in recent years like a swarm of bees to each circuit breaker factory have design, manufacturing various types of quadrupole circuit breaker on the market. The author agrees that it is to use or not to ensure the reliability and safety of power supply, so in general, it is:

(1) TN-C system. In the TN-C system, the N line and the protection line PE merge into one (PEN line). Considering the safety, it is not allowed to disconnect the PEN line at any time, so the quadrupole circuit breaker is absolutely forbidden.

(2) TT system, TN-C-S system and TN-S system can use quadrupole circuit breaker to ensure the safety of the overhaul while maintaining, but TN-C-S and TN-S system, the N pole of circuit breaker can only connect to N line, but not PEN or PE line.

(3) equipped with dual power supply switching places, because all of the neutral line system (N) is a communications, in order to ensure the power switch (circuit breaker) the maintenance safety, must use the quadrupole circuit breaker;

(4) to enter the single phase switch of the house, it is appropriate to choose a two pole circuit breaker with N pole (used as a isolator when overhauling);

(5) for the residual current protector 380/220V system (leakage breaker), neutral line must pass through the protection of zero sequence current transformer device (Tie Xin), to prevent through the neutral line, the 220V load has the leakage current and malfunction, you should use a quadrupole or with a neutral pole residual current protector.