High frequency pulse filter with preposition protective circuit

Abstract

The invention relates to a high-frequency pulse filter with pre-protection circuit, which is composed of a metal housing and an inner electric mounting circuit board, wherein an overvoltage protection circuit and a filter circuit are simultaneously arranged on the inner electric mounting circuit board; and the overvoltage protection circuit is disposed on a power input terminal of the filter circuit and composed of a group of varistors crossing over power input terminal of the filter circuit. When an abnormal high voltage occurs on any power supply circuit, the varistors carry out overvoltage short circuit to release the overhigh voltage to maintain the voltage at the power input terminal of the filter circuit at a rated voltage determined by the varistors, so that the filter circuit is prevented from being damaged by the high voltage impact and effectively protected together with power consuming equipments.

Description

Technical field [0001] The invention relates to a circuit protection device, in particular to a high-frequency pulse filter with a front protection circuit. Background technique [0002] The existing high-frequency pulse filter only has a filter function and does not have an overvoltage protection function. In electrical circuits, especially important electrical equipment such as elevators that are susceptible to interference from high-frequency pulses such as lightning strikes and surges, in addition to the need to install high-frequency pulse filters to prevent or suppress the interference effects of high-frequency pulses, In addition to ensuring the normal and orderly operation of electrical equipment, an additional overvoltage protection device is usually required to ensure the safe operation of electrical equipment. In this way, it is equivalent to setting up double safety protection measures for electrical equipment. The filter ensures that the electrical equipment works st...

AI Technical Summary

Problems solved by technology

Its shortcoming is: since the overvoltage protection device is set between the output end of the filter circuit and the power input end of the electrical equipment, the overvoltage is first passed through the filter and then sent to the overvoltage protection device, and the overvoltage protection device only It can protect electrical equipment, but does not have any protective effect on the filter, and the filter circuit is still in danger of being destroyed; the two functional components are installed separately in the form of discrete components, which takes up a lot of space and is relatively difficult to install. It is troublesome, and the recovery after damage is also troublesome, so the maintenance cost is higher

Therefore, the protection methods of electrical equipment in the prior art generally have unreasonable structures, unscientific settings, and incomplete protection, which are not ideal from the perspective of economy and practicability.

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