The components of a SPD
The SPD chiefly consists of (see Fig.1):
1) one or more nonlinear components: the live part (varistor, gas discharge tube, etc.);
2) a thermal protective device (internal disconnector) which protects it from thermal runaway at end of life (SPD with varistor);
3) an indicator which indicates end of life of the SPD;
Some SPDs allow remote reporting of this indication;
4) an external SCPD which provides protection against short circuits (this device can be integrated into the SPD).
Technology of the live part
Several technologies are available to implement the live part. They each have advantages and disadvantages:
•Zener diodes;
•The gas discharge tube (controlled or not controlled);
•The varistor (zinc oxide varistor).
The table below shows the characteristics and the arrangements of 3 commonly used technologies.
Fig.2 – Summary performance table
Dc fuse is a very easy to use protection facilities, when the abnormal circuit is often accompanied by rising current, the rising current will not only damage some key equipment, but also burn the circuit, cause a fire and directly cause great economic losses. After the DC fuse is installed, when the current exceeds the current value that […]
In lightning protection products, surge protectors and arresters are widely used. Both are important components to protect electronic equipment. There are also fundamental differences. Let us first see what these two lightning protection products are. The surge protector is to limit the instantaneous overvoltage that enters the power line and signal transmission line within the voltage range […]
DC MCB (DC miniature circuit breaker) plays a key role in the power system. First of all, DC MCB is a common switch in the control circuit, which mainly has two functions: on-off circuit and protection circuit. It adopts a special arc extinguishing and current limiting system, which can quickly disconnect the fault current of the […]
We focus on providing high-quality equipment and components to meet the needs of customers around the world.
