Conventional soft starter for motor

Abstract

The invention relates to a conventional motor soft starter, more particularly a full digital-control soft starter. The indicative signal of a signal relay of the soft starter comprises a fault signal, an overload signal, an operation signal and a start-up boost finish signal. The soft starter serves the excellent control function and multiple protective functions. Compared with the prior art, the soft starter utilizes a 16-bit single chip microcomputer to realize the full-digital date processing and to control the voltage ramp during the processes of the start-up and the stop; serves the functions of pulse bound, high-current shut-off, pump stop, built-in electronic overpower protection, phase-failure protection, over-current protection, over-temperature protection, self-diagnosis and energy conservation; can eliminate the current impact during the processes of the start-up and the stop of the motor; can reduce the capacity of the power network; and can protect the motor and the load against the mechanical shock during the processes of the start-up of the motor.

Description

[technical field] [0001] The invention relates to a conventional motor soft starter, especially a full digital control soft starter. [technical background] [0002] At present, the control function of the known soft starter is not perfect and lacks many protection functions, such as the impact of the current during the starting and stopping of the motor, the high capacity of the power grid, and the mechanical impact when the motor starts. For example, as the most widely used squirrel-cage asynchronous motor, it adopts the conditions for step-down starting: first, when the motor starts, the machine cannot withstand the impact torque of full-voltage starting; second, when the motor starts, its terminal voltage cannot meet the specification requirements ; The third is that when the motor starts, it affects the normal operation of other loads. [Content of the invention] [0003] In order to overcome the deficiencies of current motor soft starters, the present invention relate...

AI Technical Summary

Problems solved by technology

For example, as the most widely used squirrel-cage asynchronous motor, it adopts the conditions for step-down starting: first, when the motor starts, the machine cannot withstand the impact torque of full-voltage starting; second, when the motor starts, its terminal voltage cannot meet the specification requirements ; The third is that when the motor starts, it affects the normal operation of other loads