20kA/40kA/60kA/80kA/100kA/120kA surge protector What is the switch (air switch or fuse) at the front end of the surge protector?
The switch at the front end of the surge protector is also called a backup protection switch. Its main function is to disconnect the surge protector from the power grid when the surge protector fails to avoid uncontrollable accidents.
There are two main points to note in the selection of front-end switches of all surge protectors:
1. When the surge protector fails, the switch can be normally disconnected (short-circuit breaking capacity meets);
Therefore, the general switch selection should pay attention to: not greater than the rated current value of the superior switch; not greater than the maximum backup protection fuse value marked by the manufacturer.
2. When there is lightning surge intrusion, the backup protection switch has a certain tolerance, and will not malfunction and cause the surge protector to fail to function.
The ability of the switch to withstand surges should match the surge protector as much as possible.
If the surge protector of the first level T1 test meets Article 1, it is recommended to choose 100A-160A fuses.
If the second-level 40KA surge protector meets Article 1, you can choose a circuit breaker or a fuse of about 40A.