Before the advent of surge backup protectors, the backup protection devices of SPD surge protectors typically used fuses or circuit breakers to separate the short-circuit fault path of the SPD surge protector. However, when the power system fails, the SPD overcurrent short circuit, or the power frequency current passes, the current value may not reach the starting value of the overcurrent protection device (fuse, circuit breaker). The overcurrent protection device does not act, resulting in continuous current passing through the lightning protection device, causing heating and fire of the SPD surge protector.
The main function of surge protectors is to control the instantaneous overcurrent and voltage suddenly injected into the wire circuit and signal transmission line within the range that the equipment can withstand, or to introduce the strong lightning current into the ground, ensuring that the equipment or system can work safely and stably without damage caused by impact. Investing in surge protection devices, such as a signal surge protector, is essential to ensure that your wire circuits and signal transmission lines remain safe from any damage caused by power surges and spikes.

From a functional point of view, the surge backup protector selectively disconnects the power frequency current and lightning current that pass through. Generally, if the disconnect fails, when the surge protector (SPD) cannot disconnect the power frequency short-circuit current, the overcurrent protection device acts to disconnect the surge protector (SPD) from the parallel line, so that the SPD will not cause overheating and cause accidents such as fire and explosion, and at the same time ensure the continuous power supply.
At the same time, when there is lightning current passing through the SPD, this external disconnect will not have a false trip, keeping the electrical equipment in a valid state of lightning protection.
In short, the surge backup protector protects the surge protector to a certain extent and adds a safety insurance to the entire circuit. It also facilitates safe power-off when monitoring the SPD. Generally, the surge backup protector is installed at the front end of the surge protector to increase the safety of the SPD and the circuit.
The surge protector is a device used to protect electrical and electronic equipment from damage caused by lightning electromagnetic pulses. It can be said to be the "protector god" of many modern high-tech products, protecting the safety of circuits and equipment during lightning strikes. Therefore, investing in high-quality surge protection devices from a reliable surge protection devices manufacturer is essential for ensuring the longevity and reliability of your electronic equipment.

Shenzhen Tiandun has been focusing on lightning protection for 15 years, continuously keeping up with market demand, and the surge backup protector (SCB) has stronger cut-off ability and higher surge tolerance, which can more finely protect the surge protector (SPD).
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