Device for preventing self-starting motor from being damaged
By designing the control loop and the zero-sequence protection loop, the instrument shutdown signal and the motor fault signal are separated to ensure that the motor does not automatically reset and start after the fault, solving the problem of damage caused by frequent start of the motor bearing after locking, reducing the fire risk and reducing Repair costs.
Patent Information
- Application Number
- CN202420019752.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-04
- Publication Date
- 2025-01-07
- Estimated Expiration
- 2034-01-04
AI Technical Summary
The bearings of the motor and pump are frequently automatically started after locking, resulting in damage to the motor. The prior art cannot effectively prevent the fire risk caused by such failures.
A device including a control loop, a switching loop and a zero-sequence protection loop was designed. By separating the instrument shutdown signal from the motor fault signal, it ensures that the motor cannot automatically reset and start after the motor fault. It requires manual confirmation before starting, and using No. 1 and The No. 2 fuse, working position switch, test position switch, protection link point and other components realize signal separation and motor control.
It effectively avoids damage caused by automatic reset and start of motor failure, reduces maintenance costs, and disconnects the control circuit by protecting the chain point, ensuring that the motor no longer starts itself during failure, reducing fire risk.
Smart Images
Figure CN222321105U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of electrical appliances, and in particular relates to a device for preventing a self-starting motor from being damaged. Background Art
[0002] The instrument stop signal and motor fault signal of the high and low liquid level self-starting motor are tripped through the comprehensive protection series at the auxiliary point of the control circuit, but this motor is frequently started in the automatic state, and the comprehensive protection setting can be set to automatically reset for up to 4 minutes. If the motor or pump bearing is locked, it will automatically reset after four minutes after the fault signal appears. If it is not discovered in time, a fire will occur. Utility Model Content
[0003] The utility model aims to provide a device for preventing a self-starting motor from being damaged, so as to solve the technical problem that the motor is burned out due to frequent starting after the bearings of the motor and the pump are locked.
[0004] To achieve the above purpose, the specific technical solution of the device for preventing the self-starting motor from being damaged is as follows:
[0005] A device for preventing a self-starting motor from being damaged comprises a control circuit, a switch quantity circuit and a zero-sequence protection circuit; the control circuit comprises a working position switch 3, a test position switch 4, a protection interlocking point 5, a local stop button 6, a remote stop button 7, a selection switch 8, a restart point 9, a local start button 10, a remote start button 11, a manual state self-locking point 12, an automatic state start point 13, an automatic state self-locking point 14, a stop indicator light control point 15, a self-starting control point 16, an instrument interlocking control point 17, a normally closed point 18 of a No. 2 intermediate relay, a contactor coil 19, a local operation indicator light 20, The remote operation indicator light 21, the local stop indicator light 22, the remote stop indicator light 23, the No. 1 intermediate relay coil 24 and the No. 2 intermediate relay coil 25; the working position switch 3 and the test position switch 4 are connected in parallel with one end connected to the live wire of the power supply, and the other end is connected to the protection interlocking point 5, the stop indicator light control point 15, the self-starting control point 16, and the instrument interlocking control point 17; the local stop button 6, the remote stop button 7, and the selection switch 8 are connected in series with the protection interlocking point 5 in sequence; the restart point 9, the local start button 10, the remote start button 11, and the manual state self-locking point 12 are connected in parallel One end is connected to a contact of the selection switch 8, and the other end is connected to the neutral line of the power supply; one end of the automatic state starting point 13 and the automatic state self-locking point 14 connected in parallel is connected to another contact of the selection switch 8, and the other end is connected to the neutral line of the power supply; one end of the stop indicator light 22 and the remote stop indicator light 23 connected in parallel is connected in series to the stop indicator light control point 15, and the other end is connected to the neutral line of the power supply; one end of the No. 1 intermediate relay coil 24 is connected to the self-starting control point 16, and the other end is connected to the neutral line of the power supply; one end of the No. 2 intermediate relay coil 25 is connected to the instrument interlocking control point 17, and the other end is connected to the power supply The switch quantity circuit includes a contactor status point 26, a circuit breaker status point 27, an instrument interlocking status point 28 and a protector 29, and the contactor status point 26, the circuit breaker status point 27, and the instrument interlocking status point 28 are connected in series and then connected to the protector 29; the zero-sequence protection circuit includes a zero-sequence protection interlocking point 30, a circuit breaker normally open auxiliary point 31, a circuit breaker tripping coil 32, a protector power supply 33, and a No. 3 fuse 34, and the No. 3 fuse 34, the zero-sequence protection interlocking point 30, the circuit breaker normally open auxiliary point 31, and the circuit breaker tripping coil 32 are connected in series and then connected in parallel with the protector power supply 33.
[0006] The control circuit further includes a No. 1 fuse 1 and a No. 2 fuse 2. The No. 1 fuse 1 is connected in series with the working position switch 3, and the No. 2 fuse 2 is connected in series with the test position switch 4.
[0007] The device for preventing the self-starting motor from being damaged has the following advantages: the instrument shutdown signal is separated from the motor fault signal. If the motor fault signal appears, the motor starts to avoid automatic reset and cannot continue to start. The motor can be started only after manual reset is confirmed by electricity, avoiding frequent starting after the bearings of the motor and the pump are locked and burning the motor, thereby reducing the cost of repairing the motor. BRIEF DESCRIPTION OF THE DRAWINGS
[0008] Figure 1 This is a schematic diagram of the structure of a device for preventing a self-starting motor from being damaged according to the utility model;
[0009] Figure 2 This is a schematic diagram of the switch quantity circuit structure. DETAILED DESCRIPTION
[0010] In order to better understand the purpose, structure and function of the utility model, the following is a further detailed description of a device for preventing a self-starting motor from being damaged in the utility model in conjunction with the accompanying drawings.
[0011] like Figure 1-Figure 2 As shown, the device for preventing the self-starting motor from being damaged in the utility model comprises a control circuit, a switch quantity circuit and a zero-sequence protection circuit.
[0012] The control circuit includes No. 1 fuse 1, No. 2 fuse 2, working position switch 3, test position switch 4, protection interlocking point 5, local stop button 6, remote stop button 7, selection switch 8, restart point 9, local start button 10, remote start button 11, manual state self-locking point 12, automatic state start point 13, automatic state self-locking point 14, stop indicator light control point 15, self-start control point 16, instrument interlocking control point 17, No. 2 intermediate relay normally closed point 18, contactor coil 19, local operation indicator light 20, remote operation indicator light 21, local stop indicator light 22, remote stop indicator light 23, No. 1 intermediate relay coil 24, and No. 2 intermediate relay coil 25.
[0013] One end of the working position switch 3 and the test position switch 4 connected in parallel is connected to the live wire of the power supply, and the other end is connected to the protection interlocking point 5, the stop indicator light control point 15, the self-starting control point 16, and the instrument interlocking control point 17. The No. 1 fuse 1 is connected in series with the working position switch 3, and the No. 2 fuse 2 is connected in series with the test position switch 4.
[0014] The local stop button 6, remote stop button 7, and selection switch 8 are connected in series with the protection interlocking point 5 in sequence; one end of the restart point 9, local start button 10, remote start button 11, and manual state self-locking point 12 connected in parallel is connected to a contact of the selection switch 8, and the other end is connected to the neutral line of the power supply.
[0015] One end of the automatic state start point 13 and the automatic state self-locking point 14 connected in parallel is connected to another contact of the selection switch 8, and the other end is connected to the neutral line of the power supply. One end of the local stop indicator light 22 and the remote stop indicator light 23 connected in parallel is connected in series to the stop indicator light control point 15, and the other end is connected to the neutral line of the power supply. One end of the No. 1 intermediate relay coil 24 is connected to the self-start control point 16, and the other end is connected to the neutral line of the power supply. One end of the No. 2 intermediate relay coil 25 is connected to the instrument interlocking control point 17, and the other end is connected to the neutral line of the power supply.
[0016] The switch value circuit includes a contactor status point 26, a circuit breaker status point 27, an instrument interlocking status point 28 and a protector 29. The contactor status point 26, the circuit breaker status point 27 and the instrument interlocking status point 28 are connected in series and then connected to the protector 29.
[0017] The zero-sequence protection circuit includes a zero-sequence protection interlocking point 30, a circuit breaker normally open auxiliary point 31, a circuit breaker tripping coil 32, a protector power supply 33, and a No. 3 fuse 34. The No. 3 fuse 34, the zero-sequence protection interlocking point 30, the circuit breaker normally open auxiliary point 31, and the circuit breaker tripping coil 32 are connected in series and then connected in parallel with the protector power supply 33.
[0018] The control principle of this embodiment:
[0019] In the control loop, when the selector switch 8 is put into the automatic position, after the self-start control point 16 is closed, the No. 1 intermediate relay coil 24 is energized, the automatic state start point 13 is closed, the voltage passes through the No. 2 intermediate relay normally closed point 18, the contactor coil 19 is energized, and the motor starts to run. When the instrument is shut down, the instrument interlocking control point 17 is closed, the No. 2 intermediate relay coil 25 is energized, the No. 2 intermediate relay normally closed point 18 is disconnected, the contactor coil 19 loses power, and the motor stops running. If the process control is frequently started, and the motor overcurrent or overheating occurs, the protection interlocking point 5 is disconnected, the contactor coil 19 loses power, and the motor stops running.
[0020] The instrument interlocking start-stop signal is connected to the terminal of the protector 29 through the instrument interlocking status point 28, so that the low-voltage monitoring background can record the instrument shutdown status.
[0021] Change the automatic reset state of the protector 29 to manual reset. In this way, when the control circuit is put into the automatic state, the auxiliary contact of the low liquid level stop motor disconnects the control circuit through the normally closed point 18 of the second intermediate relay. When the motor fails, the control circuit is disconnected through the protection interlocking point 5, so that the two stop signals can be perfectly separated. Avoid the motor self-starting and burning the motor when the motor fails.
[0022] Although the embodiments of the present invention are described in conjunction with the accompanying drawings, those skilled in the art may make several modifications and improvements without departing from the principle of the present invention, and these modifications and improvements should also be considered to belong to the protection scope of the present invention.
Claims
1. A device for preventing a self-starting motor from being damaged, characterized in that: Including control circuit, switch circuit and zero-sequence protection circuit; The control circuit comprises a working position switch (3), a test position switch (4), a protection interlocking point (5), a local stop button (6), a remote stop button (7), a selection switch (8), a restart point (9), a local start button (10), a remote start button (11), a manual state self-locking point (12), an automatic state start point (13), an automatic state self-locking point (14), a stop indicator light control point (15), a self-starting control point (16), an instrument interlocking control point (17), a No. 2 intermediate relay normally closed point (18), a contactor coil (19), a local operation indicator light (20), a remote operation indicator light (21), a local stop indicator light (22), a remote stop indicator light (23), a No. 1 intermediate relay coil (24) and a No. 2 intermediate relay coil (25); one end of the working position switch (3) and the test position switch (4) connected in parallel is connected to the live wire of the power supply, and the other end is connected to the protection interlocking point (5), the stop indicator light control point (15), the self-starting control point (1 6) and the instrument interlocking control point (17); the local stop button (6), the remote stop button (7) and the selection switch (8) are connected in series with the protection interlocking point (5) in sequence; one end of the restart point (9), the local start button (10), the remote start button (11) and the manual state self-locking point (12) connected in parallel is connected to a contact of the selection switch (8), and the other end is connected to the neutral line of the power supply; one end of the automatic state start point (13) and the automatic state self-locking point (14) connected in parallel is connected to another contact of the selection switch (8), and the other end is connected to the neutral line of the power supply; one end of the local stop indicator light (22) and the remote stop indicator light (23) connected in parallel is connected in series with the stop indicator light control point (15), and the other end is connected to the neutral line of the power supply; one end of the No. 1 intermediate relay coil (24) is connected to the self-starting control point (16), and the other end is connected to the neutral line of the power supply; one end of the No. 2 intermediate relay coil (25) is connected to the instrument interlocking control point (17), and the other end is connected to the neutral line of the power supply; The switch quantity circuit comprises a contactor status point (26), a circuit breaker status point (27), an instrument interlocking status point (28) and a protector (29); the contactor status point (26), the circuit breaker status point (27) and the instrument interlocking status point (28) are connected in series and then connected to the protector (29); The zero-sequence protection circuit comprises a zero-sequence protection interlocking point (30), a circuit breaker normally open auxiliary point (31), a circuit breaker tripping coil (32), a protector power supply (33), and a No. 3 fuse (34); the No. 3 fuse (34), the zero-sequence protection interlocking point (30), the circuit breaker normally open auxiliary point (31), and the circuit breaker tripping coil (32) are connected in series and then connected in parallel with the protector power supply (33).
2. The device for preventing a self-starting motor from being damaged according to claim 1, characterized in that: The control circuit further comprises a No. 1 fuse (1) and a No. 2 fuse (2), wherein the No. 1 fuse (1) is connected in series with the working position switch (3), and the No. 2 fuse (2) is connected in series with the test position switch (4).