CN204391692U - A kind of electric power system rolling electricity avoids the control circuit of motor stopping - Google Patents

Abstract

The utility model provides a control circuit for avoiding motor stoppage due to swaying electricity in a power supply system, including a primary circuit and a secondary circuit, both of which are connected to a power supply; the primary circuit includes a motor and a contactor, and the The contactor is connected to the motor; the secondary circuit includes an air switch, a stop button, and a start button connected in series; the contactor coil of the contactor is connected in series with the start button, and the contactor auxiliary contact of the contactor It is connected in parallel with the start button; it also includes a power-off delay relay, and the auxiliary contact of the power-off delay relay is connected in parallel with the start button. The utility model installs a power-off delay relay in the secondary circuit, and the power-off delay relay is connected to the secondary circuit with a normally closed contact, so that the secondary circuit can still be kept normally open when the system is instantaneously swaying. After the power supply system returns to normal, the motor can start by itself to achieve the purpose of anti-shaking electricity.

Description

A control circuit for avoiding motor shutdown due to power supply system sloshing

technical field

The utility model belongs to the technical field of electric power supply and distribution engineering, and relates to a control circuit for avoiding motor stoppage by power supply system shaking.

Background technique

The motor is a necessary electrical equipment for industrial production, especially in the petrochemical process of continuous production. In recent years, due to various subjective and objective reasons, the trip of "shaking power" often causes the motor to lose power and shut down, resulting in unqualified products, raw materials and energy. waste. Especially in the petrochemical industry for continuous production devices, due to instantaneous voltage loss and power loss (commonly known as swaying power) in the power supply system such as lightning strikes, short circuits, and re-closing, the motor will stop due to instantaneous fluctuations in the external grid voltage. The interruption of the production process will bring great economic losses and potential safety hazards to production. The existing motor control circuit either has no anti-sway measures, or uses a high-priced motor integrated protector to realize the anti-sway function, which is very expensive.

Contents of the invention

In order to solve the problems existing in the prior art, the utility model provides a control circuit for avoiding motor shutdown by power supply system swaying electricity. By installing a power-off delay relay in the secondary circuit, the power-off delay relay is attached with a normally closed contact Connected to the secondary circuit, the secondary circuit can still be kept open when the system is instantaneously swayed, and the motor can start automatically after the power supply system returns to normal, achieving the purpose of anti-swaying electricity.

The utility model provides a control circuit for power supply system swaying to avoid motor shutdown, which is characterized in that: it includes a primary circuit and a secondary circuit, and the primary circuit and secondary circuit are connected to the power supply; the primary circuit includes a motor and a contact The contactor is connected with the motor; the secondary circuit includes an air switch, a stop button, and a start button connected in series; the contactor coil of the contactor is connected in series with the start button, and the contactor of the contactor The auxiliary contact of the device is connected in parallel with the start button; it also includes a power-off delay relay, and the auxiliary contact of the power-off delay relay is connected in parallel with the start button. When starting, the stop button is closed, press the start button, the auxiliary contact of the contactor is closed, the secondary circuit is maintained, the coil of the contactor is energized and is always energized due to the suction of the auxiliary contact of the contactor, so that the contactor The device pulls in and the motor runs. When the power grid fluctuates instantaneously for some reason, the voltage drops, and when the release voltage of the contactor coil is reached, the contactor is disconnected and the motor stops running. By adding a power-off delay relay in the secondary circuit, when the power grid fluctuates instantaneously for some reason, the secondary circuit is maintained by the auxiliary contact of the power-off delay relay, although the voltage drops when it reaches the release voltage of the contactor coil , the contactor is disconnected, but the secondary circuit has been maintained. When the voltage returns to normal, the contactor coil is energized, the contactor is closed, and the motor continues to run.

Preferably, it also includes a running indicator light and a shutdown indicator light; the running indicator light and the shutdown indicator light are respectively connected to the auxiliary contacts of the contactor and connected in parallel to the secondary circuit. The operating status of the motor can be clearly understood through the status of the running indicator light and the stop indicator light.

Preferably, the main contacts of the contactor are connected with the motor.

The utility model has the following beneficial effects: (1) The equipment does not stop when the instantaneous power supply system is swaying, and the impact on production safety caused by the motor shutdown is avoided. (2) Anti-sway electricity can be realized by adding a power-off delay relay. The power-off delay relay is attached with a normally closed contact connected to the secondary circuit. The transformation is simple and the cost is low. The cheaper conventional time relay is used Can. (3) The main components added in the transformation of the power supply system to prevent the motor from shutting down can be assembled and fixed with the original electrical components of the motor during the transformation, and there is no need to disassemble and assemble separately during the maintenance of the electric circuit of the motor.

Description of drawings

Fig. 1 asks the schematic diagram of circuit structure of the utility model.

In the figure: 1-stop button; 2-start button; 3-contactor coil; 4-contactor auxiliary contact; 5-running indicator light; 6-stop indicator light; 7-contactor; 8-primary circuit; 9 -secondary circuit; 10-motor; 11-power-off delay relay; 12-air switch.

Detailed ways

As shown in Figure 1, the power supply system provided by the utility model avoids the control circuit of motor shutdown, including a primary circuit 8 and a secondary circuit 9 connected to each other, and the primary circuit 8 and the secondary circuit 9 are all connected to the power supply , also includes a power-off delay relay 11; the primary circuit 8 includes a contactor 7 and a motor 10, the contactor is connected to the motor, and the main contact of the contactor 7 is connected to the controller of the motor 10; the secondary circuit 9 includes a Air switch 12, stop button 1, start button 12 together; contactor coil 3 of contactor 7 is connected in series with start button 2, contactor auxiliary contact 4 of contactor 7 is connected in parallel with start button 2, power-off delay relay 11 Auxiliary contacts are connected in parallel with start button 2. The utility model also includes a running indicator light 5 and a shutdown indicator light 6. The operation indicator light 5 and the shutdown indicator light 6 are respectively connected to the auxiliary contacts of the contactor 7, and are respectively connected in parallel on the secondary circuit 9. The status of the indicator light can clearly understand the operating status of the motor. In order to strengthen the operation protection of the motor and ensure the safety of operation.

When starting, the stop button is closed, press the start button, the auxiliary contact of the contactor is closed, the secondary circuit is maintained, the coil of the contactor is energized and is always energized due to the suction of the auxiliary contact of the contactor, so that the contactor The device pulls in and the motor runs. When the power grid fluctuates instantaneously for some reason, the voltage drops, and when it reaches the release voltage of the contactor coil, the contactor is disconnected and the motor stops running. By adding a power-off delay relay in the secondary circuit, when the power grid fluctuates instantaneously for some reason, the secondary circuit is maintained by the auxiliary contact of the power-off delay relay, although the voltage drops when it reaches the release voltage of the contactor coil , the contactor is disconnected, but the secondary circuit has been maintained. When the voltage returns to normal, the contactor coil is energized, the contactor is closed, and the motor keeps running.

Claims (3)

1. electric power system rolling electricity avoids a control circuit for motor stopping, and it is characterized in that: comprise primary circuit and secondary circuit, described primary circuit, secondary circuit are all connected with power supply; Described primary circuit comprises motor and contactor, and described contactor is connected with motor; Described secondary circuit comprises the air switch, stop botton, the start button that are cascaded; The contactor coil of described contactor is connected with described start button, and the contactor auxiliary contact of described contactor are in parallel with described start button; Also comprise power-off delay relay, the auxiliary contact of described power-off delay relay is in parallel with described start button.

2. electric power system rolling electricity as claimed in claim 1 avoids the control circuit of motor stopping, it is characterized in that: also comprise run indicator and halt indicator; Described run indicator, halt indicator are connected with described contactor auxiliary contact respectively, and are connected in parallel on respectively on described secondary circuit.

3. electric power system rolling electricity as claimed in claim 1 or 2 avoids the control circuit of motor stopping, it is characterized in that: the main contact of described contactor is connected with described motor.