News

All efforts are for our clients.

PRODUCT DISPLAY

News

How can AC circuit breaker play a protective role in DC circuit?
2018/9/14 SUMVICT476
The application of circuit breaker is very common, life also often see, many times we ignore his existence, today we talk about the molded case circuit breaker in the DC circuit how to play a protective role!
1. Overload protection and overload long delay protection. When the thermodynamic type (bimetal element) is used as overload and long time delay protection, its operation source is I2R. The effective value of AC current is equal to the average value of DC. Therefore, the intelligent low voltage circuit breaker can be used without any modification. However, for large current specifications, the secondary side current heater of current transformer can not be used because the transformer can not be used in DC circuit. If the overload long time delay release is all electromagnetic (hydraulic type, that is, oil cup type), then the delay release characteristics will change, the minimum operating current will increase 110% - 140%. Therefore, isolation circuit breaker AC full electromagnetic release can not be used in DC circuit (if it is to be redesigned).
Short circuit protection. The short-circuit protection of thermo-electro-magnetic type AC circuit breaker is based on magnet system. It is used in the filtered rectifier circuit (DC). It is necessary to multiply the setting current value of the original AC by a factor of 1.3. The full electromagnetic short-circuit protection is the same as the thermo electromagnetic type.
Share:
What are the malfunctions caused by improper circuit breaker selection?Circuit breaker use tips