SU1453565A1 - A.c. electric drive - Google Patents

Abstract

The invention relates to electrical engineering and can be used in electric drives for general industrial purposes. The purpose of the invention is to simplify an alternating current reversing drive system. This goal is achieved by including reversing contacts 7 and 8 in series with the closing contacts 4 and 5 of the power contactor. When the electric drive operates in automatic mode, the closing contacts 3-5 of the power contactor are used only when the electric motor 1 is started. The reverse is provided by two changeover contacts 7 and 8 by means of two control buttons 12 and 14. With simplicity of design, the electric drive provides an increased speed at the reverse and allows to expand the range of used contactors for controlling the electric motor 1. 1 Il. (/)

Description

(ABOUT)

The invention relates to electrical engineering and can be used in electric drives of general purpose.

The purpose of the invention is the simplification of an alternating current reversing electric drive system.

The drawing is a diagram of the AC drive,

The electric drive contains a three-phase asynchronous electric motor 1, a power contactor with a coil 2 and three contacts 3-5, some of the terminals of which are connected to the stator phases of the electric motor 1, another terminal of the first and short circuits of the contacts of the power contactor 3 reversing contactor with coil 6 and. with two changeover contacts .7 and 8, the movable terminals of which are connected to the other terminals of the second and third closing contacts 4 and 5, respectively, of the power contactor, the fixed terminals of the changeover contacts 4 and 5 are equipped with terminals for connecting the second and third phases of the power supply a reversal circuit, a stop control button 9, one output of which is connected to a terminal for connecting a power source to the first phase, another output of a control button 9 is connected to one output of a start control button 10, a shunt circuit ayuschim terminal 11 of the power contactor coil 2 whose one terminal is connected to the terminal for sub-zero exception of power source. One lead of coil 6 of reversing contactor is connected to one pin of button 12 contact. Reverse rotation, bridged by closure of contact 13 of reversing contactor button break contact 14 Direct rotation, one pin of which is connected to one pin of Start button 10, and the other pin to another. the output of the closing contact of the button 12 Reverse rotation, the other output of the button 10 The start is connected to another output of the coil 2 of the power contactor, one output of which is connected to the other output of the coil 6 of the reversing contactor .

The AC drive works as follows.

If direct rotation of an electric motor is necessary, then button 12 is not pressed, if reverse rotation of the electric motor is necessary (reverse), the control button 12 is pressed, and the switching contacts 7 and 8 of the contact groups of relay 6 occupy the opposite position shown in the drawing. After that, the button 10 is pressed, the relay 2 is triggered, which self-locks through the contact 11 and provides the closure of the contacts 4 and 5, and the motor 1 is supplied with voltage from the three-phase power source.

Dp stop the motor, press button 9. In the case when the motor rotates in the forward direction, to perform the reverse, just press button 12 and the electric motor changes the direction of rotation (relay 6 is self-locking by contact 13).

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To simplify the control of the electric motor, to increase the speed in the implementation of the reverse, a button 14 is inserted into the device. In this case, the direction of rotation of the electric motor 1 is changed during its operation by pressing the corresponding button 14 Direct rotation. - The proposed device with the simplicity of the design of the control buttons allows you to expand the range of applied-changeable relays to control the electric motor, has high reliability and speed of reversal.

Claims (1)

Invention Formula An AC motor drive containing a three-phase asynchronous motor, a power contactor with a coil to three make contacts, some of which are connected to the stator winding phases, another one of one of the making contacts of the power contactor, a reversible contactor with a coil and two changeover contacts, the movable terminals of which are connected to the other terminals of the second and third closing contacts of the power contactor, the fixed terminals ne ekidnyh contacts are provided with clamps for connecting to the second and third phases of the power source in a reversible pattern, control button Stop, one pin of which is connected to a terminal for connecting to the first phase of the power source, another pin of the control button Stop is connected to one pin of the control button Buttons Reverse rotation, bridged by the closing contact of the reversing contactor, characterized in that, for the sake of simplicity, the break contact of the Direct rotation button is inserted into it, one output of the torus is connected to one output of the Start button, and the other output is connected to Start-up, shunted by the closing end- 10 of the other end of the closing co-tact buttons Reverse rotation, another output of the Start button is connected to another output of the power contactor coil, one output of which is connected to 15 the stroke of the power contactor, the coil of which is connected to the clamp to connect the power supply to zero with one output, one output of the reversing contactor coil is connected to one output of the closing co-tact another terminal of the reversing contactor coil. Buttons Reverse rotation, bridged by the closing contact of the reversing contactor, characterized in that, for the sake of simplicity, the break contact of the Direct rotation button is inserted into it, one output of the torus is connected to one output of the Start button, and the other output is connected to buttons Reverse rotation, another output of the Start button is connected to another output of the power contactor coil, one output of which is connected to another terminal of the reversing contactor coil.