Short-circuit protection and temperature characteristic inspection system for coal mine explosion-proof electric appliance

Abstract

The invention discloses a coal mine explosion-proof electric appliance short circuit protection and temperature characteristic inspection system, which comprises a temperature measurement transmission device, a short circuit protection detection device, a data receiving and storage device and a digital display operation table, and is characterized in that the temperature measurement transmission device comprises a temperature collector and a data transmission terminal; the short-circuit protection detection equipment comprises a current transformer and a short-circuit protection data signal transmitter; and the data receiving and storing equipment comprises an explosion-proof electric appliance short-circuit protection and transient temperature data receiver, an environment temperature sensor and a data memory. According to the technical scheme, the technical problems of complicated wiring, difficult operation, low test precision and difficult real-time data transmission of the temperature test in the explosion-proof electric appliance are solved, and the space deployment flexibility, the temperature test anti-interference capability and the test level are improved. Meanwhile, the system has the multi-node distributed monitoring capability, improves the short-circuit protection and temperature characteristic inspection and test efficiency, saves the power resources, and saves the time and cost.

Description

Technical Field

[0001] This invention relates to the field of explosion-proof electrical testing technology, specifically to a short-circuit protection and temperature characteristic testing system for explosion-proof electrical equipment in coal mines. Background Technology

[0002] Explosion-proof electrical equipment is crucial for ensuring safety in high-risk industrial environments such as petrochemical plants, underground mines, and dusty environments. Its core design lies in effectively isolating external flammable and explosive media through a high-strength metal casing and advanced sealing technology, while withstanding potential internal explosion pressures. This prevents accidents caused by electrical sparks, high temperatures, or explosive energy leakage, and protects the equipment itself from damage from external explosions, ensuring reliable operation in extreme environments. However, this sealed metal structure significantly hinders heat dissipation within the equipment. Given that overheating can be a potential source of explosion, and can also accelerate the aging of internal components, reduce insulation, and even cause electrical fires, international standard IEC 60079 and Chinese standards such as GB 3836 series, GB / T14048, and MT / T 661 clearly stipulate specific requirements for the maximum surface temperature and temperature rise of explosion-proof electrical equipment.

[0003] Currently, the main temperature measurement methods include contact methods (such as thermocouples and resistance temperature detectors) and non-contact methods (such as infrared thermal imagers). Contact temperature measurement devices are simple, easy to operate, and highly accurate, making them suitable for applications requiring precise measurements; non-contact methods can achieve large-area, non-invasive temperature data acquisition. However, the enclosed metal casing of explosion-proof electrical appliances makes direct infrared scanning impossible internally and also makes it difficult to accommodate complex wiring. Furthermore, the often complex locations of test points significantly limit the practical application of both methods, impacting overall testing efficiency. Summary of the Invention

[0004] The purpose of this invention is to provide a short-circuit protection and temperature characteristic testing system for explosion-proof electrical appliances in coal mines. During the short-circuit test, the system uses thermocouples to collect the temperature at the test point, transmits the data through a wireless communication device, further processes the data, and displays it, thereby realizing the short-circuit protection and transient temperature characteristic testing of explosion-proof electrical appliances.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a coal mine explosion-proof electrical short-circuit protection and temperature characteristic testing system, comprising a temperature measurement and transmission device, a short-circuit protection detection device, a data receiving and storage device, and a digital display operating console; The temperature measurement and transmission equipment includes a temperature acquisition unit and a data transmission terminal. The temperature acquisition unit includes a thermocouple and a matching data transmission line. The test end of the thermocouple is fixed inside the explosion-proof electrical appliance at the temperature test position. The data transmission line of the thermocouple passes through the flare of the explosion-proof electrical appliance to send the data to the data transmission terminal. The data transmission terminal is placed on the outer shell of the explosion-proof electrical appliance. After receiving the data, it filters and amplifies the transmitted signal before transmitting it to the data receiving and storage device. The short-circuit protection detection equipment includes a current transformer and a short-circuit protection data signal transmitter. The short-circuit protection detection equipment is directly connected to the power grid to receive power. The current transformer is installed on the test circuit to collect the input current value of the electrical appliance under test. The short-circuit protection time is recorded by calculating the current duration. The short-circuit protection data signal transmitter transmits the current and time data to the data receiving and storage device through wireless communication. The data receiving and storage device includes an explosion-proof electrical short-circuit protection and transient temperature data receiver and a data storage device. The output terminal of the explosion-proof electrical short-circuit protection and transient temperature data receiver is connected to the data storage device, and the output terminal of the data storage device is connected to the input terminal of the digital display console. The data is then output to the digital display console through the data transmission channel. The digital display control panel includes a main unit module and a temperature anomaly alarm module. The main unit module enables functions such as data channel switching, test current adjustment, test time setting, data processing, and temperature image plotting. The temperature anomaly alarm module monitors the temperature of internal test points in real time. After identifying an abnormal test temperature, the alarm chip controls the speaker to emit an alarm sound and simultaneously cuts off the test current to ensure test safety.

[0006] Preferably, the digital display control panel further includes a display screen, a regulated power supply, and a current generator; the functions of data channel switching, test current adjustment, test time setting, data processing, and temperature image plotting are all displayed and operated on the touch screen, the regulated power supply is connected to the power grid, and the current generator supplies the test current for the explosion-proof electrical appliances.

[0007] Preferably, the data receiving and storage device further includes an ambient temperature sensor, the output of which is connected to the data storage device.

[0008] The present invention also provides an operating method, comprising the following steps: 1. Connect the explosion-proof electrical appliance to be tested in series to the test circuit using a normal working cable. Use tape or glue to attach the thermocouple terminals to the positions where measurements are required. Place the data transmission terminal on the outer casing. 2. Detect the data transmission channel operation status and set the explosion-proof electrical test parameters; then send a current adjustment command to the current generator, manually or automatically adjust the current offline, briefly close the test circuit to compare the actual current value with the test current value, continue to adjust the current offline based on the difference between the actual current value and the test current value, and continue to compare until the test current value is met, then stop the current adjustment command output, and the test current adjustment stops. 3. Cool all the explosion-proof electrical appliances under test to room temperature, adjust the test parameters of the explosion-proof electrical appliances to the rated current, close the test circuit to conduct short circuit protection and transient temperature characteristic tests of the explosion-proof electrical appliances, and calculate the short circuit protection action time and transient temperature; increase the rated current value of the explosion-proof electrical appliances, and set different short circuit current energizing test times to test the temperature characteristics of different short circuit operation conditions. IV. After the test, set the parameters of the explosion-proof electrical appliances to the rated values, restore the coal mine explosion-proof electrical short-circuit protection and temperature characteristic testing system, tidy up the experimental equipment, and complete the test.

[0009] Preferably, the test circuit is wired in a three-phase series configuration.

[0010] Preferably, the test parameters for explosion-proof electrical appliances are as follows: when adjusting the current, the current is set to 3 times the actual rated current, and during the test, the current is set to the rated operating current.

[0011] Compared with the prior art, the beneficial effects of the present invention are: This technical solution solves the technical problems of complex wiring, difficult operation, low testing accuracy, and difficulty in real-time data transmission for internal temperature testing of explosion-proof electrical appliances, and improves the flexibility of spatial deployment, strong anti-interference ability of temperature testing, and testing level.

[0012] It also features multi-node distributed monitoring capabilities, improving the efficiency of short-circuit protection and temperature characteristic testing, saving power resources, time, and costs. It provides technical support for the research and development and selection of new explosion-proof electrical products, promotes the standardization and intelligentization of explosion-proof electrical product testing, and facilitates the continuous and healthy development of the testing and inspection and explosion-proof electrical field. Attached Figure Description

[0013] Figure 1 This is a simplified structural diagram of the coal mine explosion-proof electrical short-circuit protection and temperature characteristic testing system of the present invention.

[0014] Figure 2 This is an operation flowchart of the coal mine explosion-proof electrical short-circuit protection and temperature characteristic testing system of the present invention. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] Please see Figure 1 The present invention provides a technical solution: a coal mine explosion-proof electrical short-circuit protection and temperature characteristic testing system, including a temperature measurement and transmission device, a short-circuit protection detection device, a data receiving and storage device, and a digital display operating console; The temperature measurement and transmission equipment includes a temperature acquisition unit and a data transmission terminal. The temperature acquisition unit consists of a thermocouple and a matching data transmission line. The test end of the thermocouple is fixed to the temperature testing position inside the explosion-proof electrical appliance using glue or tape. Point-to-point temperature measurement is achieved using the Seebeck effect of the thermocouple. The data transmission line of the thermocouple passes through the flared end of the explosion-proof electrical appliance to send the data to the data transmission terminal. The data transmission terminal is placed on the casing of the explosion-proof electrical appliance. After receiving the data, it filters and amplifies the transmitted signal before transmitting it to the next-level data receiving and storage device. The data transmission terminal is internally powered by a button battery for easy replacement and maintenance.

[0017] The short-circuit protection detection equipment includes a current transformer and a short-circuit protection data signal transmitter. The short-circuit protection detection equipment is directly connected to the power grid to receive power. The current transformer is installed on the test circuit to collect the input current value of the electrical appliance under test. The short-circuit protection time is recorded by calculating the current duration. The short-circuit protection data signal transmitter transmits the current and time data to the data receiving and storage device via wireless communication.

[0018] The data receiving and storage device includes an explosion-proof electrical short-circuit protection and transient temperature data receiver, an ambient temperature sensor, and a data storage device. This module is directly powered by a three-prong plug power cord connected to the power grid. The outputs of the explosion-proof electrical short-circuit protection and transient temperature data receiver and the ambient temperature sensor are connected to the data storage device via data cables to record and store internal and ambient temperature data. Data can be imported and retrieved at any time. The output of the data storage device is connected to the input of the digital display console, and outputs data to the digital display console through a data transmission channel.

[0019] Since temperature characteristics include real-time temperature and temperature rise, calculating the temperature rise requires subtracting the ambient temperature from the collected internal temperature. By designing an ambient temperature sensor, the current ambient temperature can be measured.

[0020] The digital display control panel includes a main unit module, a display screen, a temperature anomaly alarm module, a regulated power supply, and a current generator. The regulated power supply is connected to the power grid to power the module, and the current generator supplies the test current for the explosion-proof electrical equipment. The main unit module can perform functions such as data channel switching, test current adjustment, test time setting, data processing, and temperature graph plotting, all of which are displayed on the touch screen. Simultaneously, the temperature anomaly alarm module monitors the temperature of the internal test points in real time. Upon detecting an abnormal test temperature, the alarm chip controls the speaker to emit an alarm sound and simultaneously cuts off the test current to ensure test safety.

[0021] Please see Figure 2 The present invention also provides an operating method: 1. Connect the explosion-proof electrical appliance to be tested in series with the normal working cable to the test circuit (in order to ensure the balance of the three-phase current, the wiring is done in a three-phase series manner). Use tape or glue to stick the thermocouple terminals to the position where the measurement is required. Place the data transmission antenna on the outer shell, as close as possible to each temperature acquisition unit.

[0022] II. The explosion-proof electrical appliance short-circuit protection and transient temperature characteristic testing system detects the data transmission channel's operating status, sets the explosion-proof electrical appliance test parameters (the current is set to 3 times the actual rated current during current adjustment, and set to the rated operating current during actual testing), and then sends a current adjustment command to the current generator. The current can be adjusted manually or automatically offline. The test circuit is briefly closed to compare the actual current value with the test current value. Based on the difference between the actual and test current values, offline current adjustment continues until the test current value is met. At this point, the current adjustment command output stops, and the explosion-proof electrical appliance short-circuit protection and transient temperature characteristic testing current adjustment stops. Since different electrical appliances require different rated currents, the specific test current value needs to be adjusted according to the actual situation.

[0023] 3. After adjusting the current, cool all the explosion-proof electrical appliances under test to room temperature. Adjust the test parameters of the explosion-proof electrical appliances to the rated current, close the test circuit, and conduct short-circuit protection and transient temperature characteristic tests on the explosion-proof electrical appliances. Calculate the short-circuit protection action time and transient temperature. Increase the rated current value of the explosion-proof electrical appliances (without tripping within the short-circuit protection action time range) and set different short-circuit current energization test times to test the temperature characteristics under different short-circuit operation conditions.

[0024] IV. After the short-circuit protection and transient temperature characteristic test of the explosion-proof electrical equipment, set the parameters of the explosion-proof electrical equipment to the rated values, restore the short-circuit protection and transient temperature characteristic test system of the explosion-proof electrical equipment, tidy up the experimental equipment, and complete the test.

[0025] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A short-circuit protection and temperature characteristic testing system for explosion-proof electrical equipment in coal mines, characterized in that: This includes temperature measurement and transmission equipment, short-circuit protection and detection equipment, data receiving and storage equipment, and a digital display control panel; The temperature measurement and transmission equipment includes a temperature acquisition unit and a data transmission terminal. The temperature acquisition unit includes a thermocouple and a matching data transmission line. The test end of the thermocouple is fixed inside the explosion-proof electrical appliance at the temperature test position. The data transmission line of the thermocouple passes through the flare of the explosion-proof electrical appliance to send the data to the data transmission terminal. The data transmission terminal is placed on the outer shell of the explosion-proof electrical appliance. After receiving the data, it filters and amplifies the transmitted signal before transmitting it to the data receiving and storage device. The short-circuit protection detection equipment includes a current transformer and a short-circuit protection data signal transmitter. The short-circuit protection detection equipment is directly connected to the power grid to receive power. The current transformer is installed on the test circuit to collect the input current value of the electrical appliance under test. The short-circuit protection time is recorded by calculating the current duration. The short-circuit protection data signal transmitter transmits the current and time data to the data receiving and storage device through wireless communication. The data receiving and storage device includes an explosion-proof electrical short-circuit protection and transient temperature data receiver and a data storage device. The output terminal of the explosion-proof electrical short-circuit protection and transient temperature data receiver is connected to the data storage device, and the output terminal of the data storage device is connected to the input terminal of the digital display console. The data is then output to the digital display console through the data transmission channel. The digital display control panel includes a main unit module and a temperature anomaly alarm module. The main unit module enables functions such as data channel switching, test current adjustment, test time setting, data processing, and temperature image plotting. The temperature anomaly alarm module monitors the temperature of internal test points in real time. After identifying an abnormal test temperature, the alarm chip controls the speaker to emit an alarm sound and simultaneously cuts off the test current to ensure test safety.

2. The coal mine explosion-proof electrical short-circuit protection and temperature characteristic testing system according to claim 1, characterized in that: The digital display console also includes a display screen, a regulated power supply, and a current generator; The functions of data channel switching, test current adjustment, test time setting, data processing, and temperature image plotting are all displayed and operated on the touch screen. The regulated power supply is connected to the power grid, and the current generator supplies the test current for the explosion-proof electrical appliances.

3. The coal mine explosion-proof electrical short-circuit protection and temperature characteristic testing system according to claim 1, characterized in that: The data receiving and storage device also includes an ambient temperature sensor, the output of which is connected to the data storage device.

4. An operating method, implemented based on the coal mine explosion-proof electrical short-circuit protection and temperature characteristic testing system as described in claim 1, characterized in that: Includes the following steps 1. Connect the explosion-proof electrical appliance to be tested in series to the test circuit using a normal working cable. Use tape or glue to attach the thermocouple terminals to the positions where measurements are required. Place the data transmission terminal on the outer casing.

2. Check the operating status of the data transmission channel and set the test parameters for explosion-proof electrical appliances; Then, a current adjustment command is sent to the current generator to manually or automatically adjust the current offline. The test circuit is briefly closed to compare the actual current value with the test current value. Based on the difference between the actual current value and the test current value, the current is adjusted offline. The comparison continues until the test current value is met, and then the current adjustment command output is stopped, and the test current adjustment stops.

3. Cool all the explosion-proof electrical appliances under test to room temperature, adjust the test parameters of the explosion-proof electrical appliances to the rated current, close the test circuit to conduct short circuit protection and transient temperature characteristic tests of the explosion-proof electrical appliances, and calculate the short circuit protection action time and transient temperature; increase the rated current value of the explosion-proof electrical appliances, and set different short circuit current energizing test times to test the temperature characteristics of different short circuit operation conditions. IV. After the test, set the parameters of the explosion-proof electrical appliances to the rated values, restore the coal mine explosion-proof electrical short-circuit protection and temperature characteristic testing system, tidy up the experimental equipment, and complete the test.

5. The operating method according to claim 4, characterized in that: The test circuit is connected in a three-phase series configuration.

6. The operating method according to claim 4, characterized in that: The specific test parameters for explosion-proof electrical appliances are as follows: when adjusting the current, the current is set to 3 times the actual rated current; during the test, the current is set to the rated operating current.

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