Protection device of surge protector

Abstract

The invention relates to a protection device of a surge protector. The protection device comprises an isolation switch, a shunt excitation coil, a current transformer, a surge protector, a fuse, an alarm signal lamp and a signal acquisition and processing device, wherein one end of the surge protector is connected with one end of the isolation switch through the current transformer, and one end ofthe isolation switch is further connected with a negative electrode of the shunt excitation coil. The protection device is advantaged in that a delay phenomenon is generated when lightning current passes through, voltage superposition caused by voltage generation is avoided, the situation that unpredictable high voltage cannot be borne by electric equipment connected with a rear end is avoided, action criteria and the duration time are very fast and accurate by means of digital processing of a signal collecting and processing device, different protection parameters can be set according to surge protection devices of different specifications, and adjustment is easy.

Description

technical field [0001] The invention relates to a protection device for a surge protector. Background technique [0002] All kinds of lightning protection buildings are equipped with external lightning protection devices to prevent direct lightning strikes, and measures to prevent lightning surge intrusion are taken; the usual measure to prevent lightning surge intrusion is to install additional Surge protector; when a lightning surge invades, the surge protector conducts and discharges the lightning current to the ground and can suppress the overvoltage level; the surge protector is composed of a zinc oxide valve, and has a voltage of 0.01mA to 0.02mA during normal operation. mA power frequency freewheeling. [0003] After the surge protector runs for a long time, the zinc oxide material gradually deteriorates. When the power frequency leakage current reaches 100mA and above, the zinc oxide valve plate will heat up severely, which may cause the packaging shell of the surge...

AI Technical Summary

Problems solved by technology

[0005] In the first way, in actual use, the power frequency leakage current of 100mA and above may cause the packaging shell of the surge protector to catch fire, but this current value is much smaller than the rated current value of the miniature circuit breaker, so the miniature circuit breaker will not trip. As a result, the fault surge protector cannot be removed from the circuit, that is, it cannot protect the surge protector. Therefore, it is infeasible for the miniature circuit breaker to be used as a protection device for the surge protector; the second The fuse in the method has no inductance, will not generate superimposed voltage, and will not damage the protection function of the surge protector. However, in order to avoid the lightning and large current without fusing, the fuse has a large current, which is far greater than the surge protector. Fire hazard power frequency leakage current; when the surge protector generates dangerous power frequency leakage current, the fuse will not blow and cannot protect the surge protector; in the third way, the lightning current passes through the gas The discharge tube is turned on; the power frequency continuous flow of the surge protector cannot pass through the gas discharge tube, and the circuit of the miniature circuit breaker is turned on; when the power frequency leakage current of the surge protector is large, the miniature circuit breaker trips to protect the surge protector. However, the action of the gas discharge tube has a delay phenomenon, that is, when the lightning current comes, the limit voltage of the surge protector is delayed, which is unfavorable for the protection of the back-end electrical equipment; therefore, it needs further improvement

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