Over-voltage over-current protector of electronic and electric equipment

Abstract

The invention discloses an over-voltage over-current protector of electronic and electric equipment. The over-voltage over-current protector of the electronic and electric equipment comprises a power surge protective device SPD I, a surge voltage divider and a power frequency current protector, two ends of the power surge protective device SPDI are respectively connected with a live wire and a null line after a power supply distribution board access port and before a protected equipment port, the surge voltage divider is composed of an electric reactor A, a power surge protective device SPD II and an electric reactor B in a series mode, the electric reactor A at one end of the surge voltage divider is arranged on a live wire after the power surge protective device SPD I, the electric reactor B at the other end is arranged on a null line after the power surge protective device SPD I, and the power frequency current protector is composed of a PTC positive temperature coefficient thermistor, an NTC negative temperature coefficient thermistor and a TVS tube. The over-voltage over-current protector of the electronic and electric equipment has surge over-voltage limit and surge residual voltage division protection functions and power frequency over-voltage and over-current protection functions, enables the equipment fault rate to be reduced and enables the equipment aging speed to be lowered.

Description

technical field [0001] The invention relates to the technical field of power surge protectors, in particular to an overvoltage and overcurrent protector for electronic and electrical equipment with power frequency current protection. Background technique [0002] When the circuit is struck by lightning and when the inductive load or large load is turned on or off, a high operating overvoltage is often generated. This instantaneous overvoltage (or overcurrent) is called surge voltage (or surge current), which is A transient disturbance. Surge voltage phenomena are increasingly endangering the safe operation of automation equipment. Eliminating surge noise interference and preventing surge damage have always been the core issues related to the safe and reliable operation of automation equipment. [0003] Surge protective device (SPD for short), also called lightning protector, is a device that provides safety protection for various electrical equipment, instruments, communica...

AI Technical Summary

Problems solved by technology

The power of these devices is usually only tens of watts, hundreds of watts (rated current value is less than 1A), and the rated current value of the power distribution switch of the front-end equipment is selected too high when a fault occurs (because the air switch configured to match the load will trip frequently, Maintenance is inconvenient, so it is generally equipped with 25A, 16A air switch) and cannot be disconnected in time, which not only makes the maintenance cost of equipment and network system very high, but also brings great inconvenience to people's production and life

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