Motor temperature monitoring circuit and power distribution cabinet

Abstract

The application belongs to the field of large motor operation temperature monitoring and operation time recording, and particularly relates to a motor temperature monitoring circuit. The motor temperature monitoring circuit comprises a control loop, an overtime alarm indication, a temperature measurement module power supply, a timing module power supply and a signal loop. The control loop controls the temperature measurement module power supply and the timing module power supply to monitor the temperature of the motor in real time and uninterruptedly. In the scheme, the motor corresponds to a special temperature measurement module. As long as the motor is started and operated, the temperature measurement module can accurately, timely and uninterruptedly record the temperatures of five groups of on-site temperatures of the motor stator A, B and C, the shaft extension end and the non-shaft extension end bearing. The duty personnel can accurately record the operation temperature of the motor, and the accuracy and the work efficiency are improved.

Description

Technical Field

[0001] This invention belongs to the field of monitoring the operating temperature and recording the operating time of large electric motors, and specifically relates to a motor temperature monitoring circuit and a distribution cabinet. Background Technology

[0002] In industrial settings, especially in refining and chemical plants with high explosion-proof requirements, the maintenance and routine inspection of large electric motors are the primary tasks of on-duty personnel. Typically, on-duty personnel conduct routine inspections of operating equipment at regular intervals, recording motor operating temperatures, abnormal noises, and other indicators. The condition of the motors is largely determined by the measured temperature. Factors such as the amount of lubricating oil, bearing wear and damage, and the type of motor coil damage are all reflected in temperature readings, making the monitoring of motor operating temperatures particularly crucial. While on-duty personnel usually use infrared thermometers during inspections, requiring individual measurements to comprehensively record temperature data, this method is neither continuous nor comprehensive, resulting in poor effectiveness. Actual motor faults often go undetected due to time gaps or missed inspections, leading to further damage and increased losses. In addition, the maintenance and operation cycles of motors are usually difficult for on-duty personnel to accurately record. Motors in the plant area are generally used in a one-for-one backup manner. For larger motors that are idle for a long time, they are affected by the external environment and their service life is often shortened compared to motors that are frequently in operation. Therefore, the one-for-one backup motors should be periodically switched to pump operation. For this reason, it is necessary to record the motor operation time. Summary of the Invention

[0003] To address the deficiencies mentioned in the background art, this invention presents a motor temperature monitoring circuit and a power distribution cabinet.

[0004] To achieve the above objectives, the following technical solution is provided:

[0005] A motor temperature monitoring circuit includes a control loop comprising a normally open button SB1 and a composite button SB2. The composite button SB2 includes a composite normally closed switch and a composite normally open switch. The normally open button SB1 and the composite normally closed switch are connected via a normally closed relay contact KA5. The normally open button SB1 is connected in parallel with the normally open relay contact KA1 and is connected to a second power line N along with the relay coil KA1. A slow-release relay coil KT1 and a relay coil KA4 are connected in parallel with the relay coil KA1. The composite button SB2 is connected to a first power line L via the relay coil KA2. The control loop relay normally open contact KA5 is connected in parallel with the composite contact SB5. The normally closed contact SB4, the slow-release relay delayed-open normally open contact KT1, and the relay coil KA5 are connected in series to the composite normally open switch. The slow-release relay coil KT2 is connected in parallel with the relay coil KA5 and is connected to the second power line N.

[0006] The timeout alarm indicator includes a time-delayed normally open contact KT2 and a buzzer HA3HA4. The time-delayed normally open contact KT2 is connected to the first power line L, and the buzzer HA3HA4 is connected to the second power line N. The time-delayed normally open contact KT2 and the buzzer HA3HA4 are connected in series.

[0007] The power supply for the temperature measurement module is the normally open contact KA4 of the temperature measurement relay, which is connected to the first and fifth interfaces of the temperature measurement module.

[0008] The power supply for the timing module includes normally open contacts KA4 and KA5 of the timing relay connected in parallel, which are connected to the first interface of the timing module.

[0009] The seventh interface of the temperature measurement module is connected to one end of the buzzer HA1HA2, and the other end is connected to the second power line N; the second interface of the temperature measurement module and the second interface of the timing module are connected to the second power line N; the third interface of the timing module and the fourth interface of the timing module are connected to the reset button SB3, and the reset button SB3 is connected in parallel with the normally closed contact KT1 with a delay closing time; the temperature measurement module is electrically connected to the motor junction box.

[0010] Furthermore, the control circuit also includes a soft-start control board CR2. The first interface of the control board is connected to the first power line L, the second interface of the control board is connected to the second power line N, the tenth interface of the control board is equipped with the normally open contact KA1 of the control board relay and is connected to the fourth and fifth interfaces of the control board, the eighth and ninth interfaces of the control board are connected, the third interface of the control board is grounded, the fifteenth interface of the control board is connected to the relay control coil KA3 and connected to the second power line N, and the eighteenth interface of the control board is connected to the relay control coil KA2 and connected to the second power line N.

[0011] Furthermore, it also includes a signal circuit. The normally closed switch of the control board is connected in series with the HG lamp and connected between the first power line L and the second power line N. The normally open contact KA3 of the relay is connected in series with the bypass contactor coil KM and connected between the first power line L and the second power line N. The bypass contactor coil KM drives the motor. The eighteenth and twentieth interfaces of the control board are equipped with contacts, as are the fifteenth and seventeenth interfaces of the control board. The twentieth and seventeenth interfaces of the control board are connected to the first power line L.

[0012] Furthermore, a circuit breaker QF is provided connected between the first power line L and the eighteenth interface of the control board, and an HY lamp is provided connected between the second power line N and the eighteenth interface of the control board.

[0013] A power distribution cabinet, comprising a motor temperature monitoring integrated power distribution cabinet circuit, has a rectangular cabinet body with lintels on the front and rear ends of the top of the cabinet. The front end face of the cabinet body is evenly designed with mounting holes for a temperature measurement module, a motor tag, a timing module reset button, a timing module, and an over-temperature alarm buzzer. The back of the cabinet body has a cabinet door. The cabinet body has a terminal block inside, which is snapped onto a guide rail.

[0014] The beneficial effects of this invention are:

[0015] 1. The invention provides a dedicated temperature measurement module for the motor. As long as the motor is running, the temperature measurement module can accurately, in real time and continuously record the on-site temperatures of five sets of bearings: stator A, B, C, shaft extension end, and non-shaft extension end. On-duty personnel can accurately record the operating temperature of the motor, which comprehensively improves accuracy and enhances work efficiency.

[0016] 2. When the motor of this invention is turned on, the timing module starts timing, which can accurately record the running time and facilitate the recording of motor maintenance cycles and long-term running time.

[0017] 3. This invention is designed with an over-temperature alarm buzzer, which can be installed in the duty room according to the actual installation location. If the motor temperature is abnormal, the buzzer will sound an alarm, and the duty personnel can quickly find the faulty motor according to the specific indication of the temperature measurement module, so as to quickly repair it and reduce losses.

[0018] 4. The working time of the temperature measuring module and timing module of the present invention is the same as the motor start-up time, so the recorded data is more accurate. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a motor temperature monitoring circuit.

[0020] Figure 2This is a control loop diagram for a motor temperature monitoring circuit;

[0021] Figure 3 This is a circuit diagram of a signal loop and an overtime alarm indicator circuit for a motor temperature monitoring circuit.

[0022] Figure 4 This is a circuit connection diagram of a temperature measurement module, a timing module, and a motor temperature measurement junction box for a motor temperature monitoring circuit.

[0023] Figure 5 This is a schematic diagram of the front structure of the power distribution cabinet;

[0024] Figure 6 This is a schematic diagram of the reverse side structure of the power distribution cabinet;

[0025] The components include: 1. Cabinet body; 2. Cabinet top; 3. Door lintel; 4. Temperature measurement module mounting hole; 5. Motor tag; 6. Timing module reset button mounting hole; 7. Timing module mounting hole; 8. Over-temperature alarm buzzer mounting hole; 9. Cabinet door; 10. Terminal block; 11. Guide rail. Detailed Implementation

[0026] To enable those skilled in the art to understand the technical solution of the present invention more clearly, the technical solution of the present invention will be described in detail below with reference to the accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0027] This invention integrates a temperature measurement module onto one cabinet 1. Each motor is assigned a dedicated temperature measurement module based on its name or tag number. As long as the motor is running, the temperature measurement module can accurately, in real time, and continuously record the ambient temperatures of five sets of bearings: stator A, B, C, shaft extension end, and non-shaft extension end. On-duty personnel can accurately record the operating temperature of the motor, comprehensively improving accuracy and work efficiency. A timing module is also integrated into one cabinet 1. As long as the motor is running, the timing module starts timing, accurately recording the running time, which is convenient for recording the motor's maintenance cycle and long-term running time. An over-temperature alarm buzzer can be installed in the duty room according to the actual installation location. If the motor temperature is abnormal, the buzzer will sound an alarm, and on-duty personnel can quickly find the faulty motor based on the specific indication of the temperature measurement module, enabling rapid repair and minimizing losses. The operating time of the temperature measurement module and the timing module is the same as the motor's start-up time, resulting in more accurate data recording and effectively solving the various drawbacks of conventional inspections.

[0028] A motor temperature monitoring circuit includes a control loop comprising a normally open button SB1 and a composite button SB2. The composite button SB2 includes a composite normally closed switch and a composite normally open switch. The normally open button SB1 and the composite normally closed switch are connected via a normally closed relay contact KA5. The normally open button SB1 is connected in parallel with the normally open relay contact KA1 and is connected to a second power line N along with the relay coil KA1. A slow-release relay coil KT1 and a relay coil KA4 are connected in parallel with the relay coil KA1. The composite button SB2 is connected to a first power line L via the relay coil KA2. The control loop relay normally open contact KA5 is connected in parallel with the composite contact SB5. The normally closed contact SB4, the slow-release relay delayed-open normally open contact KT1, and the relay coil KA5 are connected in series to the composite normally open switch. The slow-release relay coil KT2 is connected in parallel with the relay coil KA5 and is connected to the second power line N.

[0029] The timeout alarm indicator includes a time-delayed normally open contact KT2 and a buzzer HA3HA4. The time-delayed normally open contact KT2 is connected to the first power line L, and the buzzer HA3HA4 is connected to the second power line N. The time-delayed normally open contact KT2 and the buzzer HA3HA4 are connected in series.

[0030] The power supply for the temperature measurement module is provided by the normally open contact KA4 of the temperature measurement relay, which is connected to the first and fifth interfaces of the temperature measurement module. The power supply for the temperature measurement module is provided by the control power extension relay, namely the normally open contact KA4 of the temperature measurement relay.

[0031] The power supply for the timing module includes normally open contacts KA4 and KA5 of the timing relay connected in parallel, which are connected to the first interface of the timing module. When the timing module is running, the power supply is controlled by the control power extension relay, i.e., the normally open contact KA4 of the timing relay. When the module is stopped, the power supply is controlled by the normally open contact KA5 of the timing relay.

[0032] The seventh interface of the temperature measurement module is connected to one end of the buzzer HA1HA2, and the other end is connected to the second power line N; the second interface of the temperature measurement module and the second interface of the timing module are connected to the second power line N; the third interface of the timing module and the fourth interface of the timing module are connected to the reset button SB3, and the reset button SB3 is connected in parallel with the normally closed contact KT1 with a delay closing time; the temperature measurement module is electrically connected to the motor junction box.

[0033] Pressing the stop button SB2 (compound button SB2) will simultaneously energize relay coil KA5 and slow-start relay coil KT2. The operator records the motor's running time according to the set time on KT2. If no time is recorded, an overtime alarm will be output, and buzzers HA3 and HA4 will sound an alarm. If there is no emergency and restarting within this time period is not required, restarting is not permitted. If an emergency occurs and restarting within this time period is necessary, pressing the reset button SB4 will allow restarting.

[0034] The set time of the slow-release relay coil KT1 must be longer than the set time of the slow-pull relay coil KT2. The operator should record the timer data in time after the set time of KT2 or after hearing the timeout alarm. When the set time of KT1 is reached, the timer will automatically reset to zero. At the same time, the power-on delay circuit will be de-energized, which can realize the start operation. For more reliable operation, a manual reset button SB3 is also designed.

[0035] The control circuit also includes a soft-start control board CR2. The first interface of the control board is connected to the first power line L, the second interface of the control board is connected to the second power line N, the tenth interface of the control board is equipped with the normally open contact KA1 of the control board relay and is connected to the fourth and fifth interfaces of the control board, the eighth and ninth interfaces of the control board are connected, the third interface of the control board is grounded, the fifteenth interface of the control board is connected to the relay control coil KA3 and connected to the second power line N, and the eighteenth interface of the control board is connected to the relay control coil KA2 and connected to the second power line N.

[0036] It also includes a signal circuit, where the normally closed switch of the control board is connected in series with the HG lamp between the first power line L and the second power line N, and the normally open contact KA3 of the relay is connected in series with the bypass contactor coil KM between the first power line L and the second power line N. The bypass contactor coil KM drives the motor. The eighteenth and twentieth interfaces of the control board are equipped with contacts, as are the fifteenth and seventeenth interfaces of the control board. The twentieth and seventeenth interfaces of the control board are connected to the first power line L.

[0037] A circuit breaker QF is also provided, connected between the first power line L and the eighteenth interface of the control board, and an HY light is provided, connected between the second power line N and the eighteenth interface of the control board.

[0038] The temperature measurement module is used to collect five sets of temperature signals from the stator A, stator B, stator C, and the bearings at the shaft extension end and non-shaft extension end of the motor. The temperature measurement module requires a 220V AC power supply. After the parameters of the temperature measurement module are set, when any of the five sets of temperature measurements exceeds the set value, the over-temperature alarm buzzers HA1 and HA2 will output an alarm. The timing module is used to record the running time of the motor, providing a reference for the maintenance of the motor. The timing module also requires a 220V AC power supply. When the running motor stops, the timing module reset button needs to be pressed to reset the timing.

[0039] The following is an example of the specific schematic diagram when a 90KW motor is controlled by a soft starter.

[0040] Since the temperature measuring module and timing module are no-load devices, they will not affect the normal engagement and disengagement of the bypass contactor KM. Because this invention is typically installed in a power distribution room, and the duty room for power distribution personnel is generally not located in the same room, to facilitate the detection of abnormal motor temperatures during operation, one of the over-temperature alarm buzzers HA1 and HA2 can be installed in the duty room. If an over-temperature alarm occurs, the duty personnel can quickly detect and handle it, ensuring the normal operation of the motor. The five temperature groups of stator A, B, C, and the bearings at the shaft extension and non-shaft extension ends are all led out from the motor temperature measuring junction box to the temperature measuring module. When the running motor reverses or stops, the duty personnel record the measured value indicated by the timing module, then press the timing module reset button (SB3) to reset the timing module, preparing for the next reversal or start-up recording.

[0041] A power distribution cabinet, wherein the circuit described above is set inside the cabinet body 1, the motor temperature monitoring integrated power distribution cabinet circuit, the cabinet body 1 has a cuboid structure, and the front and rear ends of the cabinet top 2 are provided with door lintels 3. The front end face of the cabinet body 1 is evenly designed with temperature measurement module mounting holes 4, motor tag identification plate 5, timing module reset button mounting holes 6, timing module mounting holes 7, and over-temperature alarm buzzer mounting holes 8. The back side of the cabinet body 1 is provided with a cabinet door 9. The cabinet body 1 is provided with a terminal block 10 inside, and the terminal block 10 is snapped onto a guide rail 11.

[0042] The above description is merely the preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any possible variations and modifications made by those skilled in the art using the methods and content disclosed above without departing from the scope of the present invention's technical solution shall fall within the scope of protection of the claims.

Claims

1. A motor temperature monitoring circuit, characterized in that: The control circuit includes a normally open button SB1 and a composite button SB2. The composite button SB2 includes a composite normally closed switch and a composite normally open switch. The normally open button SB1 and the composite normally closed switch are connected through a relay normally closed contact KA5. The normally open button SB1 is connected in parallel with the relay normally open contact KA1 and is connected to the second power line N along with the relay coil KA1. The slow-release relay coil KT1 and the relay coil KA4 are connected in parallel with the relay coil KA1. The composite button SB2 is connected to the first power line L through the relay coil KA2. The control circuit relay normally open contact KA5 is connected in parallel with the composite contact SB5. The normally closed contact SB4, the slow-release relay delayed-open normally open contact KT1, and the relay coil KA5 are connected in series to the composite normally open switch. The slow-pull relay coil KT2 is connected in parallel with the relay coil KA5 and is connected to the second power line N. The timeout alarm indicator includes a time-delayed normally open contact KT2 and a buzzer HA3HA4. The time-delayed normally open contact KT2 is connected to the first power line L, and the buzzer HA3HA4 is connected to the second power line N. The time-delayed normally open contact KT2 and the buzzer HA3HA4 are connected in series. The power supply for the temperature measurement module is the normally open contact KA4 of the temperature measurement relay, which is connected to the first and fifth interfaces of the temperature measurement module. The power supply for the timing module includes normally open contacts KA4 and KA5 of the timing relay connected in parallel, which are connected to the first interface of the timing module. The seventh interface of the temperature measurement module is connected to one end of the buzzer HA1HA2, and the other end is connected to the second power line N; the second interface of the temperature measurement module and the second interface of the timing module are connected to the second power line N; the third interface and the fourth interface of the timing module are connected to the reset button SB3, and the reset button SB3 is connected in parallel with the normally closed contact KT1 with a delay closing time; the temperature measurement module is electrically connected to the motor junction box. The set time of the slow-release relay coil KT1 is greater than the set time of the slow-draw relay coil KT2. When the set time of the slow-release relay coil KT1 is reached, the timer is automatically reset to zero, the power-on delay circuit is de-energized, and the start-up operation is realized.

2. The motor temperature monitoring circuit according to claim 1, characterized in that: The control circuit also includes a soft-start control board CR2. The first interface of the control board is connected to the first power line L, the second interface of the control board is connected to the second power line N, the tenth interface of the control board is equipped with the normally open contact KA1 of the control board relay and is connected to the fourth and fifth interfaces of the control board, the eighth and ninth interfaces of the control board are connected, the third interface of the control board is grounded, the fifteenth interface of the control board is connected to the relay control coil KA3 and connected to the second power line N, and the eighteenth interface of the control board is connected to the relay control coil KA2 and connected to the second power line N.

3. The motor temperature monitoring circuit according to claim 2, characterized in that: It also includes a signal circuit, where the normally closed switch of the control board is connected in series with the HG lamp between the first power line L and the second power line N, and the normally open contact KA3 of the relay is connected in series with the bypass contactor coil KM between the first power line L and the second power line N. The bypass contactor coil KM drives the motor. The eighteenth and twentieth interfaces of the control board are equipped with contacts, as are the fifteenth and seventeenth interfaces of the control board. The twentieth and seventeenth interfaces of the control board are connected to the first power line L.

4. The motor temperature monitoring circuit according to claim 3, characterized in that: A circuit breaker QF is also provided, connected between the first power line L and the eighteenth interface of the control board, and an HY light is provided, connected between the second power line N and the eighteenth interface of the control board.

5. A power distribution cabinet, characterized in that, The distribution cabinet is equipped with a motor temperature monitoring circuit as described in any one of claims 1-4. The cabinet has a rectangular structure, and the front and rear ends of the top of the cabinet are provided with lintels. The front end face of the cabinet is evenly designed with mounting holes for temperature measurement modules, motor tag numbers, timing module reset buttons, timing modules, and over-temperature alarm buzzers. The back of the cabinet is provided with a cabinet door. The cabinet interior is provided with terminal blocks, which are snapped onto guide rails.

Images