First, with the current limiting circuit breaker breaking capacity in arcing contact occurs when a short circuit or circuit breaker, the use of MCCB is equivalent to an increase in an arc resistance, can reduce the circuit breaker fault. When the less time, limiting the better, also can to minimize the effect caused by the short circuit because of electromagnetic and electric effect and thermal effect on the production of electrical equipment is not good, so as to prolong the breaker life.
Second, circuit breaker can play the role of "short circuit protection, short circuit protection" refers to the short circuit caused because the instantaneous tripping. Note that, after the change in load or to protect the machine, this time need MCCB. It can prevent the harm to the trip because of frequent power quality also, provide good protection for electrical equipment.
Third, circuit breaker can play the role of overload protection delay, delay protection is called in the current overload and damage to electrical equipment, circuit breaker can immediately cut off the power, try to avoid the machine damage. We should know that overload is a heat accumulation process, this action is not need special fast. Only in the current overload protection when it is good.
Fourth, circuit breaker with isolation function, isolation function is called after the circuit breaker is disconnected, avoid the harm to human body or machine leakage. A lot of trip switch will make the machine greatly reduced, and the leakage current will increase. If the environment is particularly bad, then the leakage current reaches more than two hours that may make the insulation of equipment damage, triggering a fire. While MCCB can protect equipment well, avoid fire.
Fifth, circuit breaker to leakage protection, compared with electronic leakage, interference of electromagnetic leakage is not good. When the leakage current reaches a certain value, it will make the body under threat of man and machine. If you use this time to make the circuit breaker, tripping device is automatically disconnected when the device is no longer energized, it cannot leakage. This way not only to protect the personal safety and safety of the machine, can also avoid the waste.