CN106771758A - The positioner and method of failure in cabinet control loop - Google Patents

Abstract

The invention discloses a fault positioning device and positioning method in the control circuit of an electric switch cabinet, which is composed of one or more positioning units; each positioning unit includes a first step-down rectification module, NOT gate, AND gate, trigger and fault Alarm unit; in each positioning unit, the input end of the first step-down rectification module is connected to a fault detection point of the control circuit of the electrical switchgear, the output end of the first step-down rectification module is connected to the input end of the NOT gate, and the output end of the NOT gate Connect one input terminal of the AND gate, the other input terminal of the AND gate is connected to the response signal feedback terminal of the electrical equipment through the second step-down rectifier module, the output terminal of the AND gate is connected to one input terminal of the trigger, and the other input terminal of the trigger is connected to the reset circuit, triggering The output end of the device is connected to the fault alarm unit, and the fault alarm unit is controlled to perform alarm work by outputting a high level or a low level; the invention can quickly and accurately locate the fault in the control circuit of the electrical switch cabinet.

Description

Fault location device and method in control circuit of electrical switchgear

technical field

The invention relates to the technical field of electrical engineering, in particular to a device and method for locating faults in a control circuit of an electrical switch cabinet.

Background technique

Electrical switchgear is a commonly used electrical equipment, widely used in the field of electrical power. Electrical switchgear is the equipment with the largest number, the most frequent operation and the highest failure rate in the substation, and the failure of the control circuit of the electrical switchgear accounts for more than 99% of the entire switchgear.

The start and stop of the electrical switchgear in the cement plant is controlled by DCS (Distributed Control System, distributed control system), which adopts on-site and central control methods. Among them, the control circuit of the electrical switchgear adopts AC220V voltage, and drives the main contactor to close or open through electrical components such as motor protector, field switch, interlock switch, fuse and thermal relay, so as to achieve the purpose of controlling the start and stop of the equipment. The above electrical components are installed in the field, switch cabinets and DCS cabinets, etc., and are interlocked through cable connections. If one of the components or one cable fails, it will cause the equipment to trip, but it is difficult to quickly determine the fault. Therefore, maintenance It is more difficult and will have a greater impact on the work efficiency of the cement plant.

For example, when the bucket elevator of the cement mill roller press in a cement plant suddenly stops for no reason during normal operation, causing the cement mill system to shut down, but the central control DCS shows that the site is not ready, and it can be started again after reset. At this time, manual analysis of the fault may be caused by malfunctions of fuses, thermal relays, intermediate relays in the switch cabinet, on-site switches, speed measuring switches, etc., and may also be caused by poor line contact. To analyze the specific fault point, it is necessary to conduct a thorough inspection of the switchgear, check and fasten all line terminals, and replace all original parts that may cause failure. Such a fault judgment method will cost a lot of manpower and material resources, greatly reducing the work efficiency of the cement plant. In addition, if some electrical components or lines are in poor contact or unstable, the signal will fluctuate, and it will be difficult for maintenance personnel to accurately and quickly judge the fault point by using a multimeter and an electroscope; The part is only about 20 centimeters, which poses a great safety hazard.

Contents of the invention

The first object of the present invention is to overcome the shortcomings and deficiencies of the prior art, and provide a fault location device in the control circuit of the electric switch cabinet, which can quickly and accurately locate the fault in the control circuit of the electric switch cabinet, reducing the It reduces the maintenance difficulty of the control circuit of the electrical switchgear.

The second object of the present invention is to provide a method for locating faults in the control circuit of the electrical switchgear based on the above locating device.

The third object of the present invention is to provide a device for locating faults in the control circuit of the electrical switchgear, which can also quickly and accurately locate the faults in the control circuit of the electrical switchgear, reducing the maintenance of the control circuit of the electrical switchgear difficulty.

The fourth object of the present invention is to improve a method for locating faults in the control circuit of the electrical switch cabinet based on the locating device of the above third object.

The first object of the present invention is achieved through the following technical solutions: a fault positioning device in the control circuit of an electrical switch cabinet, which is composed of one or more positioning units;

Each positioning unit includes a first step-down rectification module, a NOT gate, an AND gate, a trigger and a fault alarm unit;

In each positioning unit, the input end of the first step-down rectification module is connected to a fault detection point of the control circuit of the electrical switchgear, the output end of the first step-down rectification module is connected to the input end of the NOT gate, and the output end of the NOT gate is connected to One of the input terminals of the AND gate, the other input terminal of the AND gate is connected to the output terminal of the second step-down rectification module, the input terminal of the second step-down rectification module is connected to the feedback terminal of the response signal of the electrical equipment, and the output terminal of the AND gate is connected to the trigger The reset input terminal of the trigger is connected to the reset circuit, and the reset circuit resets the trigger to zero; the output terminal of the trigger is connected to the fault alarm unit, and the fault alarm unit is controlled by the output high level. Alarm work.

Preferably, the fault alarm unit includes a contactor and a light-emitting diode, and the two terminals of a group of coils of the contactor are respectively connected to the output terminal of the trigger and the ground, and the working state of the contactor is controlled through the output of the trigger; the DC power supply is connected in series A pair of contacts of the device and the light-emitting diode are grounded; the light-emitting diode is controlled by the working state of the contactor.

Preferably, the reset circuit includes a reset switch, an electrolytic capacitor and a resistor, wherein the zero-setting input terminal of the trigger is grounded through a resistor, and the zero-setting input terminal of the trigger is connected to a DC power supply through a parallel reset switch and an electrolytic capacitor, and is triggered by a reset switch pair reset to zero;

The flip-flop is an RS flip-flop or a JK flip-flop;

In each positioning unit, a first optocoupler is connected between the first step-down rectification module and the input end of the NOT gate, and a second photoelectric coupler is connected between the second step-down rectification module and the input end of the AND gate. coupler;

When there are multiple positioning units, the second step-down rectification module connected to the AND gate input terminal of each positioning unit is the same, and the reset circuit connected to the flip-flop of each positioning unit is the same.

The second object of the present invention is achieved through the following technical solutions: a positioning device for faults in the control circuit of the electric switch cabinet based on the above-mentioned first object realizes a fault location method in the control circuit of the electric switch cabinet, it is characterized in that the steps are as follows:

S1. First, reset the trigger in the positioning unit, so that the trigger outputs a low level after reset; then connect the input end of the first step-down rectifier module of the positioning unit to the fault detection point of the control circuit of the electrical switchgear, and locate The input end of the second step-down rectification module of the unit is connected to the electrical equipment response signal feedback end;

S2. After the electrical equipment is started, the signal output by the response signal feedback terminal of the electrical equipment is stepped down and rectified by the second step-down rectifier module, and then outputs a high level to the input terminal of the AND gate, and the positioning unit is started to work;

S3. When the fault detection point of the electrical switchgear control circuit connected to the input end of the first step-down rectification module in the positioning unit does not fail, the voltage input by the input end of the first step-down rectification module is input to the NOT gate, after receiving the high-level signal output from the output terminals of the first step-down rectifier module and the second step-down rectifier module, the NOT gate outputs a low level to the AND gate, and at this time, the output terminal of the AND gate outputs a low level to trigger When the trigger is set to one input terminal, the output state of the trigger remains unchanged, so the output low level is sent to the fault alarm unit, and the fault alarm unit does not work;

S4. When the fault detection point of the electrical switchgear control circuit connected to the input terminal of the first step-down rectifier module in the positioning unit fails, the input terminal of the first step-down rectifier module has no voltage signal input. At this time, the first step-down rectifier module The NOT gate connected to the output terminal of the rectifier module outputs a high level signal to the AND gate. At this time, the output terminal of the AND gate outputs a high level signal to the input terminal of the flip-flop set to one, and the output of the trigger is set to one, so the output high level signal is sent to the fault alarm unit , controlling the fault alarm unit to perform alarm work, prompting the fault detection point of the electrical switch cabinet control circuit connected to the input end of the first step-down rectifier module of the positioning unit to be faulty.

Preferably, the fault alarm unit includes a contactor and a light-emitting diode, and the two terminals of a group of coils of the contactor are respectively connected to the output terminal of the trigger and the ground, and the DC power supply is connected in series with a pair of contacts of the contactor and the light-emitting diode and then grounded;

In the step S3, when the output terminal of the trigger outputs a low level, a group of coils of the contactor connected to the trigger is not energized, and the contactor does not work at this time, and a pair of contacts connected to the light-emitting diode in the contactor are on. state, the light-emitting diode is off;

In the step S4, when the output terminal of the trigger outputs a high level, a group of coils of the contactor connected to the trigger is energized, at this time the contactor works, and a pair of contacts connected to the light-emitting diode in the contactor are in a closed state , the light-emitting diode becomes bright; it prompts that the fault detection point of the control circuit of the electrical switchgear connected to the input terminal of the first step-down rectifier module of the positioning unit is faulty.

The third object of the present invention is achieved through the following technical solutions: a fault location device in the control circuit of an electrical switchgear, which is composed of one or more location units;

Each positioning unit includes a first step-down rectification module, a NOT gate, an AND gate, a trigger and a fault alarm unit;

In each positioning unit, the input end of the first step-down rectification module is connected to a fault detection point of the control circuit of the electrical switchgear, the output end of the first step-down rectification module is connected to the input end of the NOT gate, and the output end of the NOT gate is connected to One of the input terminals of the AND gate; the other input terminal of the AND gate is connected to the output terminal of the second step-down rectification module, the input terminal of the second step-down rectification module is connected to the response signal feedback terminal of the electrical equipment, and the output terminal of the AND gate is connected to the trigger The zero-setting input terminal of the trigger is connected to the reset circuit, and the reset circuit resets the trigger; the output terminal of the trigger is connected to the fault alarm unit, and the fault alarm unit is controlled by the output low level to give an alarm. Work.

Preferably, the fault alarm unit includes a contactor and a light-emitting diode, and the two terminals of a group of coils of the contactor are respectively connected to the output terminal of the trigger and the power supply, and the working state of the contactor is controlled through the output of the trigger; the DC power supply is connected in series A pair of contacts of the device and the light-emitting diode are grounded, and the light-emitting diode is controlled by the working state of the contactor.

Preferably, the reset circuit includes a reset switch, an electrolytic capacitor and a resistor, wherein the set-one input terminal of the trigger is grounded through the resistor, and the set-one input terminal of the trigger is connected to a DC power supply through a parallel reset switch and an electrolytic capacitor, and is triggered by the reset switch pair device reset;

The flip-flop is an RS flip-flop or a JK flip-flop; in each positioning unit, a first optocoupler is connected between the first step-down rectification module and the input terminal of the NOT gate, and the second step-down rectification module A second photocoupler is connected between the module and the input end of the AND gate;

When there are multiple positioning units, the second step-down rectification module connected to the AND gate input terminal of each positioning unit is the same, and the reset circuit connected to the flip-flop of each positioning unit is the same.

The fourth object of the present invention is achieved through the following technical solutions: a positioning device for faults in the control circuit of the electric switch cabinet based on the above-mentioned second object realizes a fault location method in the control circuit of the electric switch cabinet, it is characterized in that the steps are as follows:

S1. First reset the trigger in the positioning unit, so that the trigger outputs a high level after reset, and then the input end of the first step-down rectifier module of the positioning unit is connected to the fault detection point of the control circuit of the electrical switch cabinet, and the positioning unit The input terminal of the second step-down rectifier module is connected to the feedback terminal of the response signal of the electrical equipment;

S2. After the electrical equipment is started, the signal output by the response signal feedback terminal of the electrical equipment is stepped down and rectified by the second step-down rectifier module, and then outputs a high level to the input terminal of the AND gate, and the positioning unit is started to work;

S3. When the fault detection point of the electrical switchgear control circuit connected to the input end of the first step-down rectification module in the positioning unit does not fail, the voltage input by the input end of the first step-down rectification module is input to the Inverter, after receiving the high-level signal output from the output terminals of the first step-down rectifier module and the second step-down rectifier module, the not-gate outputs a low level to the AND gate, and the output terminal of the AND gate outputs a low level to the trigger setting Zero input terminal; at this time, the output state of the trigger remains unchanged, so the output high level is sent to the fault alarm unit, and the fault alarm unit does not work;

S4. When the fault detection point of the electrical switchgear control circuit connected to the input terminal of the first step-down rectifier module in the positioning unit fails, the input terminal of the first step-down rectifier module has no voltage signal input. At this time, the first step-down rectifier module The NOT gate connected to the output terminal of the rectifier module outputs a high-level signal to the AND gate, and the output terminal of the AND gate outputs a high-level signal to the zero-setting terminal of the trigger; at this time, the output of the trigger is set to zero, and the output low-level signal is sent to the fault alarm unit to control The fault alarm unit performs alarm work, prompting the fault detection point of the control circuit of the electrical switchgear connected to the input end of the first step-down rectifier module of the positioning unit to be faulty.

Preferably, the fault alarm unit includes a contactor and a light-emitting diode, and the two terminals of a group of coils of the contactor are respectively connected to the output terminal of the trigger and the power supply, and the DC power supply is connected in series with a pair of contacts of the contactor and the light-emitting diode and then grounded;

In the step S3, when the output terminal of the trigger outputs a high level, a group of coils of the contactor connected to the trigger is not energized, and the contactor does not work at this time, and a pair of contacts connected to the light-emitting diode in the contactor are in the open state. state, the light-emitting diode is off;

In the step S4, when the output terminal of the trigger outputs a low level, a group of coils of the contactor connected to the trigger is energized, and at this time the contactor works, and a pair of contacts connected to the light-emitting diode in the contactor are in a closed state , the light-emitting diode becomes bright; it prompts that the fault detection point of the control circuit of the electrical switchgear connected to the input terminal of the first step-down rectifier module of the positioning unit is faulty.

Compared with the prior art, the present invention has the following advantages and effects:

(1) The positioning unit of the positioning device of the present invention includes a first step-down rectification module, a NOT gate, an AND gate, a trigger and a fault alarm unit; wherein the input end of the first step-down rectification module is connected to a failure of the electrical switchgear control circuit At the detection point, the output terminal of the first step-down rectification module is connected to the input terminal of the NOT gate, and the output terminal of the NOT gate is connected to one of the input terminals of the AND gate; the other input terminal of the AND gate is connected to the electrical equipment through the second step-down rectification module The response signal feedback terminal, the output terminal of the AND gate is connected to one of the input terminals of the trigger, the other input terminal of the trigger is connected to the reset circuit, and the trigger is reset through the reset circuit, and the output terminal of the trigger is connected to the fault alarm unit. Output high level or low level to control the failure alarm unit to alarm. When the fault detection point of the electrical switchgear control circuit connected to the first step-down rectifier module of the positioning unit fails, the fault alarm unit of the positioning unit performs alarm work, so the present invention can perform alarm work according to whether the fault alarm unit of the positioning unit , to confirm whether the fault detection point of the electrical switchgear control circuit connected to the first step-down rectifier module of the positioning unit is faulty, which has the advantages of fast and accurate fault confirmation. In addition, the positioning device of the present invention may include a plurality of positioning units, wherein the first step-down rectification module of the positioning unit is respectively connected to the place where the control circuit of the electrical switchgear needs to perform fault detection. When a fault occurs, the corresponding fault of the connected positioning unit The alarm unit will perform the alarm work, and the present invention can realize simultaneous detection of multiple fault points in the control circuit of the electric switch cabinet through multiple positioning units, thereby greatly improving the working efficiency of fault detection. The invention overcomes the technical problems of low efficiency, great difficulty and potential safety hazards in the prior art of electric switchgear control loop fault detection.

(2) In the positioning unit of the positioning device of the present invention, the fault alarm unit is composed of a contactor and a light-emitting diode. The trigger of the positioning unit drives the work of the light-emitting diode by controlling the working state of the contactor. It can be judged intuitively whether there is a fault.

(3) In the positioning device of the present invention, when there are multiple positioning units, the second step-down rectification module connected to the AND gate input end of each positioning unit is the same, and the reset circuit connected to the trigger of each positioning unit is the same One, the structure of the positioning device of the present invention is greatly simplified, and through such a structure, each positioning unit of the positioning device of the present invention can be started and reset at the same time, which simplifies the operation process.

Description of drawings

Fig. 1 is a structural diagram of each positioning unit in the positioning device of Embodiment 1 of the present invention.

Fig. 2 is a structural diagram of the positioning device in Embodiment 1 of the present invention.

3 is a schematic diagram of each fault alarm unit corresponding to each positioning unit in the positioning device of Embodiment 1 and Embodiment 2 of the present invention.

Figure 4 is a schematic diagram of the control circuit of the electrical switchgear of the common motor WE07.

Fig. 5 is a structural diagram of each positioning unit in the positioning device of Embodiment 2 of the present invention.

Fig. 6 is a structural diagram of the positioning device in Embodiment 2 of the present invention.

detailed description

The present invention will be further described in detail below in conjunction with the embodiments and the accompanying drawings, but the embodiments of the present invention are not limited thereto.

Example 1

This embodiment discloses a fault location device in the control circuit of an electric switch cabinet, which is composed of one or more location units;

As shown in Figure 1, each positioning unit includes a first step-down rectification module, a NOT gate, an AND gate, a flip-flop and a fault alarm unit; in each positioning unit, the input terminal of the first step-down rectification module is connected to A fault detection point of the control circuit of the electrical switchgear, the output terminal of the first step-down rectifier module is connected to the input terminal of the NOT gate, and the output terminal of the NOT gate is connected to one of the input terminals of the AND gate; the other input terminal of the AND gate is connected to the second input terminal of the AND gate. The output end of the second step-down rectification module, the input end of the second step-down rectification module is connected to the response signal feedback end of the electrical equipment, the output end of the AND gate is connected to the set-one input end of the flip-flop, and the zero-setting input end of the flip-flop passes through the reset circuit Connect the power supply and ground respectively, and the output end of the trigger is connected to the fault alarm unit, and the fault alarm unit is controlled by the output high level to perform alarm work.

In this embodiment, the fault alarm unit includes a contactor and a light-emitting diode, and the two terminals of a group of coils of the contactor are respectively connected to the output terminal and the ground of the trigger, and the working state of the contactor is controlled by the output of the trigger; the DC power supply is connected in series A pair of contacts of the contactor and the light-emitting diode are grounded, and the light-emitting diode is controlled to turn on and off through the working state of the contactor.

In this embodiment, the reset circuit includes a reset switch, an electrolytic capacitor and a resistor, wherein the zero-setting input of the trigger is grounded through a resistor, and the zero-setting input of the trigger is connected to a DC power supply through a parallel reset switch and an electrolytic capacitor. flip-flop resets. Before each positioning unit in this embodiment starts positioning work, it must first be reset. At this time, since the positioning unit is not in the working state, the output of the NOT gate circuit is a low-level signal, so the set-one input of the flip-flop inputs is low level, when the reset switch is pressed during the reset process, the zero-setting input terminal of the flip-flop inputs high level, at this time the output terminal of the trigger is set to zero, and the reset is completed. When the Panasonic reset switch, the zero-setting input of the trigger Input low level at the terminal, at this time the flip-flop is in a hold state, and the input level at the output terminal remains low.

As shown in Figure 1, the flip-flop in this embodiment is an RS flip-flop, the S terminal of the RS flip-flop is the one-set terminal, and the R terminal is the zero-setting terminal. Of course, the flip-flop in this embodiment can also be other types. Flip-flops, such as JK flip-flops, etc.

In each positioning unit of this embodiment, a first photocoupler is connected between the first step-down rectification module and the input end of the NOT gate, and a second photocoupler is connected between the second step-down rectification module and the input end of the AND gate. device. The isolation of the input and the output is realized by the first photocoupler and the second photocoupler, and the interference of the high voltage in the control circuit of the electrical switchgear to the positioning unit of this embodiment is reduced.

This embodiment also discloses a method for locating faults in the control circuit of the electrical switch cabinet based on the above-mentioned fault location device in the control circuit of the electrical switch cabinet. The steps are as follows:

S1. First, reset the trigger in the positioning unit, so that the trigger outputs a low level after reset; then connect the input end of the first step-down rectifier module of the positioning unit to the fault detection point of the control circuit of the electrical switchgear, and locate The input end of the second step-down rectification module of the unit is connected to the electrical equipment response signal feedback end;

S2. After the electrical equipment is started, the signal output by the response signal feedback terminal of the electrical equipment is stepped down and rectified by the second step-down rectifier module, and then outputs a high level to the input terminal of the AND gate, and the positioning unit is started to work;

S3. When the fault detection point of the electrical switchgear control circuit connected to the input end of the first step-down rectification module in the positioning unit does not fail, the voltage input by the input end of the first step-down rectification module is input to the NOT gate, after receiving the high-level signal output from the output terminals of the first step-down rectifier module and the second step-down rectifier module, the NOT gate outputs a low level to the AND gate, and at this time, the output terminal of the AND gate outputs a low level to trigger When the trigger is set to one input terminal, the output state of the trigger remains unchanged, so the output low level is sent to the fault alarm unit, and the fault alarm unit does not work;

S4. When the fault detection point of the electrical switchgear control circuit connected to the input terminal of the first step-down rectifier module in the positioning unit fails, the input terminal of the first step-down rectifier module has no voltage signal input. At this time, the first step-down rectifier module The NOT gate connected to the output terminal of the rectifier module outputs a high level signal to the AND gate. At this time, the output terminal of the AND gate outputs a high level signal to the input terminal of the flip-flop set to one, and the output of the trigger is set to one, so the output high level signal is sent to the fault alarm unit , controlling the fault alarm unit to perform alarm work, prompting the fault detection point of the electrical switch cabinet control circuit connected to the input end of the first step-down rectifier module of the positioning unit to be faulty.

In the above step S3 of this embodiment, when the output terminal of the trigger outputs a low level, a group of coils of the contactor connected to the trigger is not powered, and the contactor does not work at this time, and a pair of contacts of the light-emitting diode are connected In the open state, the light-emitting diode is not bright;

In the above step S4 of this embodiment, when the output terminal of the trigger outputs a high level, a group of coils of the contactor connected to the trigger is energized, and at this time the contactor works, and a pair of contacts connected to the light-emitting diode in the contactor are closed state, the light-emitting diode lights up; it prompts that the fault detection point of the control circuit of the electrical switchgear connected to the input end of the first step-down rectifier module of the positioning unit is faulty.

In this embodiment, when there are multiple positioning units, the second step-down rectification module connected to the AND gate input terminal of each positioning unit is the same, and the reset circuit connected to the flip-flop of each positioning unit is the same .

As shown in Figure 2, the positioning device in this embodiment includes 4 positioning units, which are respectively the first positioning unit, the second positioning unit, the third positioning unit and the fourth positioning unit, and the electrical switch cabinet can be completed by the 4 positioning units Simultaneous detection of 4 fault points in the control loop. In this embodiment, the second step-down rectifier modules connected to the AND gate input ends of the four positioning units are the same, and the reset circuits connected to the flip-flops of the four positioning units are the same. As shown in Figure 3, among the two contacts of a pair of contacts of the contactors Q1, Q2, Q3 and Q4 of the fault alarm units of the four positioning units in this embodiment, one of the contacts is connected to the DC power supply, and the other is connected to the DC power supply. point to ground through the LED. When the coils of the contactors Q1, Q2, Q3, and Q4 are energized, a pair of contacts on them are closed, and the correspondingly connected LEDs light up.

As shown in Figure 4, it is a schematic diagram of the electrical switchgear control circuit of the common motor WE07. In this embodiment, the AND gate input terminals of the four positioning units are connected to the same output terminal of the second step-down rectification module, and the output terminals of the second step-down rectification module The input end is connected to the response signal feedback end of the motor WE07. The input end of the first step-down rectifier module of the first positioning unit is connected to the wire behind the fuse of the motor WE07 control loop; the input end of the first step-down rectifier module of the second positioning unit is connected to the thermal relay circuit of the motor WE07 control loop; The input end of the first step-down rectification module of the third positioning unit is connected to the on-site switch circuit of the motor WE07 control loop; the input end of the first step-down rectification module of the fourth positioning unit is connected to the DCS ready signal circuit of the motor WE07 control loop.

In this embodiment, the positioning unit resets the trigger therein before the fault detection, and after the reset is completed, when the motor WE07 starts, the positioning unit starts the fault detection work. If the fuse insurance fails, the input terminal of the first step-down rectifier module of the first positioning unit will input a low level to a NOT gate, and at this time, the flip-flop of the first positioning unit outputs a high level to control the first positioning unit The failure alarm unit of the first unit works, that is, the light-emitting diode LED1 of the failure alarm unit of the first unit turns on.

If the thermal relay malfunctions, the input terminal of the first step-down rectifier module of the second positioning unit will input a low level to a NOT gate, and at this time, the flip-flop of the second positioning unit outputs a high level to control the output of the second positioning unit. The fault alarm unit works, that is, the fault alarm unit light-emitting diode LED2 of the second unit turns bright.

If the on-site switch malfunctions or a fault causes shutdown, the input terminal of the first step-down rectifier module of the third positioning unit will input a low level to a NOT gate, and at this time the trigger of the third positioning unit outputs a high level to control the third The fault alarm unit of the positioning unit works, that is, the fault alarm unit light-emitting diode LED3 of the third unit turns on.

If the DCS ready signal is lost and causes a shutdown, the input terminal of the first step-down rectifier module of the fourth positioning unit will input a low level to a NOT gate, and at this time, the flip-flop of the fourth positioning unit outputs a high level to control the fourth positioning unit The fault alarm unit of the unit works, that is, the fault alarm unit light-emitting diode LED3 of the fourth unit turns bright.

Therefore, through the locating device of this embodiment, the operator can locate the fault point in the control circuit of the electrical switchgear according to the locating unit where the brightened light-emitting diode is located. There is no need to manually detect and eliminate points one by one, which greatly improves the efficiency of fault detection. It can be seen that the positioning device can quickly and accurately locate the fault in the control circuit of the electrical switchgear, which reduces the difficulty of maintenance of the control circuit of the electrical switchgear.

Example 2

This embodiment discloses a fault location device in the control circuit of an electric switch cabinet, which is composed of one or more location units;

As shown in FIG. 5 , each positioning unit in this embodiment includes a first step-down rectification module, a NOT gate, an AND gate, a flip-flop and a fault alarm unit.

In each positioning unit, the input end of the first step-down rectification module is connected to a fault detection point of the control circuit of the electrical switchgear, the output end of the first step-down rectification module is connected to the input end of the NOT gate, and the output end of the NOT gate is connected to One of the input terminals of the AND gate; the other input terminal of the AND gate is connected to the output terminal of the second step-down rectification module, the input terminal of the second step-down rectification module is connected to the response signal feedback terminal of the electrical equipment, and the output terminal of the AND gate is connected to the trigger The zero-setting input terminal of the trigger, and the one-setting input terminal of the trigger are respectively connected to the power supply and ground through the reset circuit; the output terminal of the trigger is connected to the fault alarm unit, and the fault alarm unit is controlled to perform alarm work through the output low level.

In this embodiment, the fault alarm unit includes a contactor and a light-emitting diode. The two terminals of a group of coils of the contactor are respectively connected to the output terminal of the trigger and the power supply, and the output of the trigger is used to control the working state of the contactor; the DC power supply is connected in series. A pair of contacts of the contactor and the light-emitting diode are grounded, and the light-emitting diode is controlled to turn on and off through the working state of the contactor.

In this embodiment, the reset circuit includes a reset switch, an electrolytic capacitor, and a resistor, wherein the set-one input of the trigger is grounded through a resistor, and the set-one input of the trigger is connected to a DC power supply through a parallel reset switch and an electrolytic capacitor, and is controlled by the reset switch. flip-flop resets. Before each positioning unit in this embodiment starts positioning work, it must first be reset. At this time, since the positioning unit is not in the working state, the output of the NOT gate circuit is a low-level signal, so the zero-setting input terminal of the flip-flop inputs It is low level, when the reset switch is pressed during the reset process, the set-one input of the flip-flop inputs a high level, at this time the trigger output is set to one, and the reset is completed. When the Panasonic reset switch, the set-one input of the flip-flop Input low level at the terminal, at this time the flip-flop is in a hold state, and the input level at the output terminal remains high and remains high.

As shown in Figure 5, the flip-flop in this embodiment is an RS flip-flop; the S terminal of the RS flip-flop is the one-set terminal, and the R terminal is the zero-setting terminal. Of course, the flip-flop in this embodiment can also be other types of triggers Devices, such as JK flip-flops, etc.

In each positioning unit, a first photocoupler is connected between the first step-down rectification module and the input end of the NOT gate, and a second photocoupler is connected between the second step-down rectification module and the input end of the AND gate;

This embodiment also discloses a method for locating faults in the control circuit of the electrical switchgear based on the above-mentioned locating device, the steps are as follows:

S1. First reset the trigger in the positioning unit, so that the trigger outputs a high level after reset, and then the input end of the first step-down rectifier module of the positioning unit is connected to the fault detection point of the control circuit of the electrical switch cabinet, and the positioning unit The input terminal of the second step-down rectifier module is connected to the electrical equipment response signal feedback terminal;

S2. After the electrical equipment is started, the signal output by the response signal feedback terminal of the electrical equipment is stepped down and rectified by the second step-down rectifier module, and then outputs a high level to the input terminal of the AND gate, and the positioning unit is started to work;

S3. When the fault detection point of the electrical switchgear control circuit connected to the input end of the first step-down rectification module in the positioning unit does not fail, the voltage input by the input end of the first step-down rectification module is input to the Inverter, after receiving the high-level signal output from the output terminals of the first step-down rectifier module and the second step-down rectifier module, the not-gate outputs a low level to the AND gate, and the output terminal of the AND gate outputs a low level to the trigger setting Zero input terminal; at this time, the output state of the trigger remains unchanged, so the output high level is sent to the fault alarm unit, and the fault alarm unit does not work;

S4. When the fault detection point of the electrical switchgear control circuit connected to the input terminal of the first step-down rectifier module in the positioning unit fails, the input terminal of the first step-down rectifier module has no voltage signal input. At this time, the first step-down rectifier module The NOT gate connected to the output terminal of the rectifier module outputs a high-level signal to the AND gate, and the output terminal of the AND gate outputs a high-level signal to the zero-setting terminal of the trigger; at this time, the output of the trigger is set to zero, and the output low-level signal is sent to the fault alarm unit to control The fault alarm unit performs alarm work, prompting the fault detection point of the control circuit of the electrical switchgear connected to the input end of the first step-down rectifier module of the positioning unit to be faulty.

In the above step S3 of this embodiment, when the output terminal of the trigger outputs a high level, a group of coils of the contactor connected to the trigger in the fault alarm unit are not energized, and the contactor does not work at this time. A pair of contacts are in the open state, and the light-emitting diode is off;

In the above step S4 of this embodiment, when the output terminal of the trigger outputs a low level, a group of coils of the contactor connected to the trigger in the fault alarm unit is energized, and the contactor works at this time, and a pair of light-emitting diodes connected to the contactor The contact is in a closed state, and the light-emitting diode lights up; it prompts that the fault detection point of the electrical switchgear control circuit connected to the input end of the first step-down rectifier module of the positioning unit is faulty.

In this embodiment, when there are multiple positioning units, the second step-down rectification module connected to the AND gate input terminal of each positioning unit is the same, and the reset circuit connected to the flip-flop of each positioning unit is the same.

As shown in Figure 6, the positioning device in this embodiment includes 4 positioning units, which are respectively the first positioning unit, the second positioning unit, the third positioning unit and the fourth positioning unit, and the electrical switch cabinet can be completed by the 4 positioning units Simultaneous detection of 4 fault points in the control loop. Wherein it is the same as Embodiment 1, as shown in Figure 3, among the two contacts of a pair of contacts of the contactors Q1, Q2, Q3 and Q4 of the fault alarm units of the four positioning units of the present embodiment, one of the contacts Connect the DC power supply, and the other contact is grounded through the LED. When the coils of the contactors Q1, Q2, Q3, and Q4 are energized, a pair of contacts on them are closed, and the correspondingly connected LEDs light up.

As shown in Figure 4, it is a schematic diagram of the electrical switchgear control circuit of the common motor WE07. In this embodiment, the AND gate input terminals of the four positioning units are connected to the same output terminal of the second step-down rectification module, and the output terminals of the second step-down rectification module The input terminal is connected to the response signal feedback terminal of the motor WE07. The input end of the first step-down rectifier module of the first positioning unit is connected to the wire behind the fuse of the motor WE07 control loop; the input end of the first step-down rectifier module of the second positioning unit is connected to the thermal relay circuit of the motor WE07 control loop; The input end of the first step-down rectification module of the third positioning unit is connected to the on-site switch circuit of the motor WE07 control loop; the input end of the first step-down rectification module of the fourth positioning unit is connected to the DCS ready signal circuit of the motor WE07 control loop.

In this embodiment, the positioning unit resets the trigger therein before the fault detection, and after the reset is completed, when the motor WE07 starts, the positioning unit starts the fault detection work.

If the fuse fuse breaks down, the input terminal of the first step-down rectifier module of the first positioning unit will input a low level to a NOT gate, at this time, the flip-flop of the first positioning unit outputs a low level to control the first positioning unit The failure alarm unit of the first unit works, that is, the light-emitting diode LED1 of the failure alarm unit of the first unit turns on.

If the action of the thermal relay fails, the input terminal of the first step-down rectifier module of the second positioning unit will input a low level to the NOT gate, and at this time, the trigger of the second positioning unit outputs a low level to control the second positioning unit. The fault alarm unit works, that is, the fault alarm unit light-emitting diode LED2 of the second unit turns bright.

If the on-site switch malfunction or failure causes shutdown, the input terminal of the first step-down rectifier module of the third positioning unit will input a low level to a NOT gate, and at this time, the trigger of the third positioning unit outputs a low level to control the third The fault alarm unit of the positioning unit works, that is, the fault alarm unit light-emitting diode LED3 of the third unit turns on.

If the DCS ready signal is lost and causes a shutdown, the input terminal of the first step-down rectifier module of the fourth positioning unit will input a low level to a NOT gate, and at this time, the trigger of the fourth positioning unit outputs a low level to control the fourth positioning unit. The fault alarm unit of the unit works, that is, the fault alarm unit light-emitting diode LED3 of the fourth unit turns bright.

Therefore, through the above-mentioned positioning device in this embodiment, the operator can also locate the fault point in the control circuit of the electrical switchgear according to the positioning unit where the brightened light-emitting diode is located. There is no need to manually detect and eliminate points one by one, which greatly improves the efficiency of fault detection. It can be seen that the positioning device can quickly and accurately locate the fault in the control circuit of the electrical switchgear, which reduces the difficulty of maintenance of the control circuit of the electrical switchgear.

The above-mentioned embodiment is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited by the above-mentioned embodiment, and any other changes, modifications, substitutions, combinations, Simplifications should be equivalent replacement methods, and all are included in the protection scope of the present invention.

Claims (10)

1. A locating device for a fault in an electric switch cabinet control circuit, characterized in that it is composed of one or more locating units; Each positioning unit includes a first step-down rectification module, a NOT gate, an AND gate, a trigger and a fault alarm unit; In each positioning unit, the input end of the first step-down rectification module is connected to a fault detection point of the control circuit of the electrical switchgear, the output end of the first step-down rectification module is connected to the input end of the NOT gate, and the output end of the NOT gate is connected to One of the input terminals of the AND gate, the other input terminal of the AND gate is connected to the output terminal of the second step-down rectification module, the input terminal of the second step-down rectification module is connected to the feedback terminal of the response signal of the electrical equipment, and the output terminal of the AND gate is connected to the trigger The reset input terminal of the trigger is connected to the reset circuit, and the reset circuit resets the trigger to zero; the output terminal of the trigger is connected to the fault alarm unit, and the fault alarm unit is controlled by the output high level. Alarm work. 2. the locating device of fault in the electrical switchgear control circuit according to claim 1, it is characterized in that, fault alarm unit comprises contactor and light-emitting diode, and two terminals of one group of coils of contactor correspond to respectively connect trigger The output terminal and the ground control the working state of the contactor through the output of the trigger; the DC power supply is connected in series with a pair of contacts of the contactor and the light-emitting diode and then grounded; the light-emitting diode is controlled by the working state of the contactor. 3. the locating device of fault in the electrical switchgear control loop according to claim 1, it is characterized in that, reset circuit comprises reset switch, electrolytic capacitor and resistance, wherein the zero setting input end of trigger is grounded by resistance, the trigger's The zero-setting input terminal is connected to the DC power supply through a parallel reset switch and an electrolytic capacitor, and the reset switch resets the trigger to zero; The flip-flop is an RS flip-flop or a JK flip-flop; In each positioning unit, a first optocoupler is connected between the first step-down rectification module and the input end of the NOT gate, and a second photoelectric coupler is connected between the second step-down rectification module and the input end of the AND gate. coupler; When there are multiple positioning units, the second step-down rectification module connected to the AND gate input terminal of each positioning unit is the same, and the reset circuit connected to the flip-flop of each positioning unit is the same. 4. a positioning device based on the fault location in the electrical switch cabinet control loop according to claim 1 realizes the location method of the fault in the electrical switch cabinet control loop, it is characterized in that, the steps are as follows: S1. First, reset the trigger in the positioning unit, so that the trigger outputs a low level after reset; then connect the input end of the first step-down rectifier module of the positioning unit to the fault detection point of the control circuit of the electrical switchgear, and locate The input end of the second step-down rectification module of the unit is connected to the electrical equipment response signal feedback end; S2. After the electrical equipment is started, the signal output by the response signal feedback terminal of the electrical equipment is stepped down and rectified by the second step-down rectifier module, and then outputs a high level to the input terminal of the AND gate, and the positioning unit is started to work; S3. When the fault detection point of the electrical switchgear control circuit connected to the input end of the first step-down rectification module in the positioning unit does not fail, the voltage input by the input end of the first step-down rectification module is input to the NOT gate, after receiving the high-level signal output from the output terminals of the first step-down rectifier module and the second step-down rectifier module, the NOT gate outputs a low level to the AND gate, and at this time, the output terminal of the AND gate outputs a low level to trigger If the trigger is set to an input terminal, the output state of the trigger remains unchanged, so the output low level is sent to the fault alarm unit, and the fault alarm unit does not work; S4. When the fault detection point of the electrical switchgear control circuit connected to the input terminal of the first step-down rectifier module in the positioning unit fails, the input terminal of the first step-down rectifier module has no voltage signal input. At this time, the first step-down rectifier module The NOT gate connected to the output terminal of the rectifier module outputs a high level signal to the AND gate. At this time, the output terminal of the AND gate outputs a high level signal to the input terminal of the flip-flop set to one, and the output of the trigger is set to one, so the output high level signal is sent to the fault alarm unit , controlling the fault alarm unit to perform alarm work, prompting the fault detection point of the electrical switch cabinet control circuit connected to the input end of the first step-down rectifier module of the positioning unit to be faulty. 5. the location method of fault in the electrical switchgear control circuit according to claim 4, it is characterized in that, fault alarm unit comprises contactor and light-emitting diode, and two terminals of one group of coils of contactor correspond to respectively connect trigger The output terminal and the ground, a pair of contacts of the DC power supply series contactor and the light-emitting diode are then grounded; In the step S3, when the output terminal of the trigger outputs a low level, a group of coils of the contactor connected to the trigger is not energized, and the contactor does not work at this time, and a pair of contacts connected to the light-emitting diode in the contactor are on. state, the light-emitting diode is off; In the step S4, when the output terminal of the trigger outputs a high level, a group of coils of the contactor connected to the trigger is energized, at this time the contactor works, and a pair of contacts connected to the light-emitting diode in the contactor are in a closed state , the light-emitting diode becomes bright; it prompts that the fault detection point of the control circuit of the electrical switchgear connected to the input terminal of the first step-down rectifier module of the positioning unit is faulty. 6. A device for locating faults in the control circuit of an electrical switchgear, characterized in that it consists of one or more locating units; Each positioning unit includes a first step-down rectification module, a NOT gate, an AND gate, a trigger and a fault alarm unit; In each positioning unit, the input end of the first step-down rectification module is connected to a fault detection point of the control circuit of the electrical switchgear, the output end of the first step-down rectification module is connected to the input end of the NOT gate, and the output end of the NOT gate is connected to One of the input terminals of the AND gate; the other input terminal of the AND gate is connected to the output terminal of the second step-down rectification module, the input terminal of the second step-down rectification module is connected to the response signal feedback terminal of the electrical equipment, and the output terminal of the AND gate is connected to the trigger The zero-setting input terminal of the trigger is connected to the reset circuit, and the reset circuit resets the trigger; the output terminal of the trigger is connected to the fault alarm unit, and the fault alarm unit is controlled by the output low level to give an alarm. Work. 7. The location device of fault in the electric switchgear control circuit according to claim 6, it is characterized in that, fault alarm unit comprises contactor and light-emitting diode, and two terminals of one group of coils of contactor correspond to connect trigger respectively The output terminal and the power supply control the working state of the contactor through the output of the trigger; the DC power supply is connected in series with a pair of contacts of the contactor and the light-emitting diode and then grounded, and the light-emitting diode is controlled by the working state of the contactor. 8. The locating device of fault in the electric switchgear control circuit according to claim 6, it is characterized in that, reset circuit comprises reset switch, electrolytic capacitor and resistance, wherein the one input end of trigger is grounded by resistance, the trigger's Set one input terminal to connect the DC power supply through the parallel reset switch and electrolytic capacitor, and reset the trigger by the reset switch; The flip-flop is an RS flip-flop or a JK flip-flop; in each positioning unit, a first optocoupler is connected between the first step-down rectification module and the input terminal of the NOT gate, and the second step-down rectification module A second photocoupler is connected between the module and the input end of the AND gate; When there are multiple positioning units, the second step-down rectification module connected to the AND gate input terminal of each positioning unit is the same, and the reset circuit connected to the flip-flop of each positioning unit is the same. 9. A positioning device based on the fault location in the electrical switch cabinet control loop according to claim 6 realizes the location method of the fault in the electrical switch cabinet control loop, it is characterized in that, the steps are as follows: S1. First reset the trigger in the positioning unit, so that the trigger outputs a high level after reset, and then the input end of the first step-down rectifier module of the positioning unit is connected to the fault detection point of the control circuit of the electrical switch cabinet, and the positioning unit The input terminal of the second step-down rectifier module is connected to the feedback terminal of the response signal of the electrical equipment; S2. After the electrical equipment is started, the signal output by the response signal feedback terminal of the electrical equipment is stepped down and rectified by the second step-down rectifier module, and then outputs a high level to the input terminal of the AND gate, and the positioning unit is started to work; S3. When the fault detection point of the electrical switchgear control circuit connected to the input end of the first step-down rectification module in the positioning unit does not fail, the voltage input by the input end of the first step-down rectification module is input to the Inverter, after receiving the high-level signal output from the output terminals of the first step-down rectifier module and the second step-down rectifier module, the not-gate outputs a low level to the AND gate, and the output terminal of the AND gate outputs a low level to the trigger setting Zero input terminal; at this time, the output state of the trigger remains unchanged, so the output high level is sent to the fault alarm unit, and the fault alarm unit does not work; S4. When the fault detection point of the electrical switchgear control circuit connected to the input terminal of the first step-down rectifier module in the positioning unit fails, the input terminal of the first step-down rectifier module has no voltage signal input. At this time, the first step-down rectifier module The NOT gate connected to the output terminal of the rectifier module outputs a high-level signal to the AND gate, and the output terminal of the AND gate outputs a high-level signal to the zero-setting terminal of the trigger; at this time, the output of the trigger is set to zero, and the output low-level signal is sent to the fault alarm unit to control The fault alarm unit performs alarm work, prompting the fault detection point of the control circuit of the electrical switchgear connected to the input end of the first step-down rectifier module of the positioning unit to be faulty. 10. The location method of fault in the electric switchgear control circuit according to claim 9, it is characterized in that, fault alarm unit comprises contactor and light-emitting diode, and two terminals of one group of coils of contactor correspond to respectively connect trigger The output terminal and the power supply, a pair of contacts of the DC power supply series contactor and the light-emitting diode are then grounded; In the step S3, when the output terminal of the trigger outputs a high level, a group of coils of the contactor connected to the trigger is not energized, and the contactor does not work at this time, and a pair of contacts connected to the light-emitting diode in the contactor are in the open state. state, the light-emitting diode is off; In the step S4, when the output terminal of the trigger outputs a low level, a group of coils of the contactor connected to the trigger is energized, and at this time the contactor works, and a pair of contacts connected to the light-emitting diode in the contactor are in a closed state , the light-emitting diode becomes bright; it prompts that the fault detection point of the control circuit of the electrical switchgear connected to the input terminal of the first step-down rectifier module of the positioning unit is faulty.