Design method for frame circuit breaker

Abstract

The invention discloses a design method for a frame circuit breaker and belongs to the field of electrical equipment. The design method includes the steps that an insulating base, a terminal, a fixed contact, a moving contact, an operating mechanism, an energy storage mechanism, a controller and a rotating mechanism are provided, and the terminal is partially exposed out of the insulating base; a connecting post is arranged on the terminal, the connecting post is partially embedded into the terminal and is in interference fit with the terminal, a first conductive columnar part in interference fit with a power busbar is arranged on the connecting post, a second conductive columnar part is coaxially arranged inside the first columnar part, the first columnar part and the second columnar part are in interference fit, and the thermal expansion coefficient of the second columnar part is larger than that of the first columnar part. The design method has the advantages that a larger conduction area is generated through the same lap joint length, then current density is reduced, and low temperature rise of the terminal is achieved; the use number of busbars is reduced, and resources are saved; the electrical clearance or safety distance is increased, and the electrical safety of equipment is improved.

Description

technical field [0001] The invention relates to the field of electric equipment, in particular to a design method of a frame circuit breaker. Background technique [0002] In the existing complete set of power equipment factory, construction workers install the frame circuit breaker in the power distribution cabinet. The terminal blocks of the frame circuit breaker are usually directly connected with the power busbar, and the power busbar is directly connected to the terminal block. The busbars are usually connected by lap joints and then fastened with bolts. Such as image 3 with Figure 4 As shown, this connection method needs to overlap the busbar and the terminal by a certain length, so that the current density of the contact surface can be maintained within a certain range, so that the temperature rise at the connection can meet the relevant standards. In order to reduce the temperature rise at the joint, it is usually necessary to increase the overlapping length of t...

AI Technical Summary

Problems solved by technology

And increasing the overlap length will increase the amount of busbars, thereby increasing the manufacturing cost

Fastening bolts will reduce the electrical clearance or safety distance between conductive parts and non-conductive parts. In order to keep the electrical clearance or safety distance unchanged, it is necessary to increase the distance between the terminal and the non-conductive Large spacing will inevitably lead to larger dimensions of the entire frame circuit breaker

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