Electronic thermorelay

Abstract

The invention is an electronic thermal relay, composed mainly of shell, terminal, reset button, indicator light and circuit device, where the circuit device is arranged in the lower part of the shell, a measurer is arranged in the upper part of the shell and provided with equipment instruction electromagnetic control relay, single-phase double-metal thermal component and Hall component to detect traveling distance of the single-phase double-metal thermal component, and the circuit device includes a protecting circuit, composed mainly of IC (integrated circuit), the Hall component is connected with the IC, the measured signal of the Hall component instructs the electromagnetic control relay to act through IC operation instruction equipment. Its switching-on and -off are clear and the current overload protection for the motor is effective and accurate.

Description

1. Technical field [0001] The invention relates to a relay, in particular to an electronic thermal relay. 2. Background technology [0002] Thermal relay is a kind of electrical appliance that relies on the heat generated when the current passes through the heating element, so that the bimetal sheet is heated and bent to push or command the action of the mechanism. It is mainly used for overload protection of the motor, protection of phase failure and current unbalanced operation, and other The control of the heating state of electrical equipment is mainly composed of three parts: the heating element, the control contact and the action system, and the reset mechanism. Existing thermal relays mainly use bimetal strips and resistance wires or strips to form thermal elements, and each phase of the three-phase power supply is in one group. When the motor is overloaded, the current increases, the resistance wire heats up, the bimetal sheet bends in a single direction, and the li...

AI Technical Summary

Problems solved by technology

But it has the following disadvantages and deficiencies: (1) Three sets of thermal elements are required to drive a complex mechanical mechanism, which makes it difficult to ensure the consistency of action; (2) The thermal element is installed on the bracket in the air, and the actuator needs to be pushed after being heated and bent. Then push the limit switch, because the mechanism resistance and the error of the mechanical mechanism are very large, it is difficult to complete the precise protection action; (3) due to the slow heating action of the thermal element, when the mechanism and the limit switch are close to the zero boundary state, the limit switch The contacts are in a non-connected state, and it is easy to damage the electrical equipment and the motor; (4) Although there is a phase-break protection function, the effect is very poor. It needs to act for a long time, and only the other two-phase thermal elements are working, so the time to push the limit switch is greatly increased, it is impossible to achieve the purpose of protection in a timely manner, and it is easy to damage electrical equipment and motors

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