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Protector Folding action

Protector
Folding action
The functions of this backup protection device are as follows:
1. When abnormal transient overvoltage of power supply causes SPD conduction to break through and short circuit, it may cause power trip and power failure, or serious fire accident. Installation of external disconnector means that the circuit can be quickly disconnected when SPD is short circuited. It is specially noted here that this external disconnector must have the ability to break the short-circuit current, otherwise it will lead to serious consequences of arc burning and fire!
2. When SPD deteriorates (withstands lightning current impact or transient over-voltage impact), causing the starting voltage to drop below the power supply voltage, the power frequency leakage current will rapidly increase. When this current is only a few amperes, the SPD thermal tripping mechanism can disconnect the circuit. When the current is more than 10A, the SPD heats and ignites faster than the heat transfer speed, that is, the SPD has already ignited before the heat transfer reaches the tripping temperature, The external disconnector must disconnect the circuit before causing SPD fire to prevent fire.
3. When SPD has lightning current, the external disconnector will not trip by mistake, so that the lightning protection of electrical equipment is always effective.
Folding advantages
The backup protection devices of traditional surge protective devices are mostly circuit breakers and fuses. As backup protection devices, circuit breakers are prone to misoperation under the impact of surge. The surge withstand capacity is low. In order to obtain higher surge withstand capacity, the selected rated current will be relatively large, which will result in the inability to break the short circuit current to ground. The withstand capacity of fuse with the same rated current is lower than that of circuit breaker, and there is also the problem of larger selected rated current.
SCB (special backup protection device for surge protector), as a new generation of backup protection device for surge protector, has strong breaking capacity and higher surge withstand capacity, and its short-circuit action current is far lower than the traditional backup protection device under the condition of considering both breaking capacity and surge endurance. It can effectively break the low short-circuit current and provide more sophisticated short-circuit protection for the surge protector.