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Machinery Industry Standard of the People's Republic of China
Low-voltage electrical appliance impulse voltage tester
JB/T7083-93
This standard specifies the basic parameters, technical requirements, test methods and inspection rules of low-voltage electrical appliance impulse voltage tester. This standard is applicable to impulse voltage testers with a rated output impulse voltage peak value of 30kV and below, which meet the impulse voltage test requirements of GB1497.
2 Reference standards
GB1497
GB4793
GB6593
GB3100
GB3101
Basic parameters
High voltage test technology
Oscilloscope and bee-value voltmeter for impulse testBasic standards for low-voltage electrical appliances
Safety requirements for electrical measuring instruments
Inspection rules for electronic measuring instruments
International system of units and its application
General principles for quantities, units and symbolsLow-voltage electrical appliance impulse voltage testers are divided into six specifications according to the output impulse voltage peak value: 1kV, 2.5kV, 5.0kV.10kV, 20kV, 3.1
30kV.
3.2 Parameters of output standard impulse voltage wave
3.2.1 The standard impulse voltage wave simulates the full wave of lightning impulse. The parameters of the standard lightning impulse full wave are shown in Figure 1. The apparent wave front time T is 1.2μs, and the apparent half-wave peak time T is 50μs. u
T,-1.67T,
Approved by the Ministry of Machinery Industry on October 8, 1993
Implemented on January 1, 1994
3.2.2 The allowable deviation of the output impulse voltage wave is as follows: a. Deviation between the standard impulse wave and the measured impulse wave Wave front time: ±30%
Half peak time: 20%
JB/T7083-93
When accurately measured, the overshoot and superimposed oscillation near the bee value allow the amplitude of a single peak to not exceed 5% of the peak value. b.
4 Technical requirements
General requirements
4.1.1 The impulse voltage tester can be used normally under the following environmental conditions: a.
The ambient air temperature does not exceed 40℃ and is not lower than 5℃; atmospheric pressure: 70.0-106.0kPa;
Relative air humidity: 20%~80%;
4.1.2 Input voltage and frequency of the impulse voltage tester a.
Rated voltage of single-phase AC: ~220V±10%Rated frequency of single-phase AC: 50Hz±2%
4.2 Safety of impulse voltage tester
4.2.1 The safety of the impulse voltage tester shall comply with the requirements of Class 1 electronic instruments specified in GB4793, except that it must meet the requirements of this standard.
4.2.2 The impulse voltage tester shall be designed and manufactured to have good protection against electric shock. a.
The accessible metal parts or components shall not be charged, and their charged parts and components must be protected by covering materials or insulating materials; various operating axes are not allowed to be charged;
External knobs, handles, etc. used to control components or components with power supply voltage should be made of insulating materials. 4.2.3 The leakage current value of any level of the impulse voltage tester power supply flowing to the accessible surface of the instrument shall not be greater than 5mA. 4.2.4 The impulse voltage tester shall have sufficient insulation resistance and dielectric strength. a.
The insulation resistance value between the power input and the shell of the impulse voltage tester shall not be less than 2MQ; the power input and the shell of the impulse voltage tester shall be able to withstand a test voltage of 1.5kV, a waveform of an actual sine wave, and a frequency of 50Hz for 1min without breakdown or flashover; c.
The output high-voltage end to the exposed metal casing of the instrument (the casing is not electrically connected to the internal circuit) shall be able to withstand a working voltage of 70% of the rated output voltage of the instrument for 0.5$. Note: During the insulation resistance and dielectric strength tests, resistors and other components connected in parallel with the insulation may be open-circuited. 4.2.5 The accessible metal parts of the impulse voltage tester that will be energized when the insulation fails shall be permanently and reliably connected to the grounding terminal inside the instrument or the grounding pin of the instrument inlet socket, and shall meet the following requirements: The ground connection shall not use a screwless terminal, a. All parts of the grounding terminal shall not be corroded due to contact between these parts and the copper or any other metal of the grounding wire; the resistance value between the grounding terminal or grounding pin and the parts required to be connected thereto shall not be greater than 0.5α. c. A clear and durable grounding symbol shall be marked near the grounding terminal or grounding pin, and the symbol shall not be marked on removable parts such as screws. d.
4.2.6 The internal structure and circuit connection of the impulse voltage tester shall meet the following requirements: a.
It shall be possible to prevent the insulation between the circuit parts connected to the power grid or the circuit used for such purpose and the accessible conductor from being short-circuited due to accidental loosening of the wires, screws, etc. b. The strength of the wire connection points subject to mechanical stress shall not rely solely on welding. The length of the screws fixing the back cover, bottom plate, etc. shall not endanger the creepage distance and electrical clearance between the accessible parts and the live parts. c.
To the value below that specified in this standard, the terminal, screws, cover screws, handles and knob fastening screws shall be screwed into metal nuts or metal parts. 25bZxz.net
JB/T708393
Replaceable parts that determine the electrical clearance and creepage distance shall be marked. e.
It is not allowed for the accessible parts to be internally connected to the power circuit with neutral line. f. When the cover is opened during normal operation and the parts with voltages above 1kV become accessible, the cover and accessible parts shall be marked with a red lightning symbol.
4.2.7 The creepage distance and electrical clearance between the various parts of the impulse voltage tester shall comply with the provisions of Article 9.5 of GB4793. 4.2.8 The parts directly connected to the power grid shall meet the following requirements, and the power socket on the impulse voltage tester shall comply with the relevant standards. a.
b. The soft wire connecting the impulse voltage tester and the power grid must be a three-core wire, one of which is a yellow-green two-color wire that can only be connected to the grounding pin, and the length of the soft wire should not be less than 2.5m. c. The type and size of the plug for connecting the impulse voltage tester to the power grid should comply with the relevant standards. 4.3 Appearance quality of the impulse voltage tester
4.3.1 The shell of the impulse voltage tester should have no obvious defects, and the coating of the shell should have no delamination and peeling. 4.3.2 The shell of the impulse voltage tester should have no sharp edges. 4.3.3 The symbols of various quantities and units on the panel of the impulse voltage tester shall comply with GB3100- and GB3101, and the printing or engraving shall be clear and obvious and not easy to erase.
4.4 Output impulse voltage peak detection accuracy At rated voltage, the output voltage detection accuracy deviation of the impulse voltage tester shall not exceed 3%. 4.5 Storage time of impulse voltage peak
At rated output voltage, after the peak voltage is sampled, the indicated value of the impulse voltage tester shall remain unchanged. If the indicated value decays slowly, the peak decay shall generally not exceed 1% of the displayed value within 5s. 4.6 Drop test
The impulse voltage tester shall have sufficient mechanical strength, the fastening of parts and electrical connections shall be safe and reliable, the internal wiring shall not damage its insulation, and it shall be able to withstand the drop test:
After the test, the instrument shall undergo the withstand voltage test specified in Article 4.2.4, the live parts shall not become accessible parts, the shell shall not have obvious cracks, and the insulation shall not be damaged, loose or fall off. 4.7 Power switch
The impulse voltage tester must be equipped with a power switch and shall meet the following requirements: a.
When the power switch is turned off, all parts of the instrument and all levels of the power supply shall be disconnected, but the circuit of the protective grounding system shall not be cut off. , b.
The power switch shall have sufficient breaking capacity. e.
The on and off positions of the power switch shall be clearly marked and shall not be indicated only by a signal light. 5. Inspection method
Test conditions and requirements for instruments and equipment
The environmental conditions of the test shall meet the following requirements: 5.1.1
Ambient air temperature: 20±2℃
Relative humidity: 45%~75%
Atmospheric pressure: 86~106kPa
5.1.2The test power supply shall meet the following requirements: a.
Rated AC voltage: 220V, ±1%,
Rated frequency: 50Hz, ±1%.
5.2 Appearance quality inspection
Use visual inspection
The inspection results should comply with the provisions of Article 4.3.
5.3 Mark inspection
Use visual inspection and the following test to inspect.
JB/T7083-93
Use a cloth with gasoline, alcohol or water to gently wipe, the mark should not be wiped off. The inspection results should comply with the provisions of Article 4.2.6d, Article 4.2.6g, Article 4.3.3, Article 4.7c. 5.4 Measurement of impulse voltage waveform parameters
The measurement circuit is shown in Figure 2.
Voltage divider
Impact instrument
Testing instrument and equipment requirements:
Oscilloscope or
bee value voltmeter
The measurement error of the time parameter of the impulse waveform detection should not be greater than ±4%, the vertical scale factor of the oscilloscope is stable and its error is not greater than 2%, the time scale is stable and its error is not greater than 2%; the input impedance is greater than 1M and not greater than 50pF. The voltage divider of the voltage divider measurement system is a pure resistance type voltage divider. Under the premise of not excessively increasing the load of the impulse voltage generator, a voltage divider with a lower resistance value is selected. The resistance is generally several kn to 20 kQ. The high-voltage end of the voltage divider uses a shielded electrode. The high and low voltage arms of the voltage divider should use materials of the same specifications. The voltage divider ratio should be stable and its error should not exceed 0.2%. The response characteristics of the voltage divider require that its square wave response time does not exceed 0.2μs. If the capacitance of the test product does not exceed 10% of the modulation capacitance in the instrument, it can be tested without connecting the test product. If the capacitance value of the test product is greater than 10% of the modulation capacitance value of the C
wave, the test product must be brought in or connected with an equivalent capacitor for testing after the test product. d. The high-voltage lead is not longer than 2m. The impulse voltage tester with a single-polarity lightning wave output should be tested at the upper and lower limits of the effective output range provided by the product. The impulse voltage tester with positive and negative polarity output should be measured separately in the same twenty polarities as the single-polarity auxiliary output. The measurement results shall comply with the provisions of Article 3.2.
5.5 Peak voltage value error measurement
The measurement circuit is shown in Figure 2
The accuracy of the calibrated impulse peak voltage meter is 1%. To meet the requirements of GB813, the calibration factor of the peak meter is calibrated. The error of the displayed calibration signal of the internal and external calibration of the routine calibration should not exceed 0.5%. The input impedance of the calibrator is greater than 1Mα and not greater than 50pF. The voltage divider measurement system must comply with the requirements of 5.4.b. The high-voltage lead is not greater than 2m. Within the test range provided by the product, the peak voltage measurement relative error of the impulse voltage meter, the inspection result shall comply with the provisions of Article 4.4. 5.6 Storage time measurement of impulse voltage peak Under the conditions of Article 5.5, check the peak voltage measurement attenuation value of the impulse voltage meter between 5s and the calibration error. The inspection result shall comply with the provisions of Article 4.5.
5.7 Load test
Measure the circuit according to Figure 2. When the external equivalent capacitance is 10% of the instrument's modulating capacitance value, the peak value of the impulse voltage meter output voltage should not be less than the rated output voltage of the instrument. 5.8 Output short circuit test
The output short circuit test is to test the instrument's ability to withstand the condition of a short circuit at the output end. The instrument is first adjusted to output the rated impulse voltage, and then the high-voltage output end is short-circuited with the test ground end. The impulse interval time is not less than 5s. After three impulses, the instrument should be able to work normally after returning to normal test conditions. 5.9 Anti-interference test
The high potential end of the voltage divider of the impulse voltage tester is suspended or short-circuited to the voltage divider ground end. The interference level of the peak voltage indication value of the instrument should be less than 0.5%.
5.10 Leakage current measurement
The measurement circuit is shown in Figure 3
The instrument should be placed on an insulating table and operated at 1.1 times the rated voltage until the temperature reaches equilibrium. During the measurement, the instrument should be powered by an isolation transformer, and the leakage current value between each pole of the power plug and the accessible metal parts (including the grounding terminal) should be measured in turn.
The measurement results should comply with the provisions of Article 4.2.3.
5.11 Insulation resistance measurement and withstand voltage test 5.11.1 Insulation resistance measurement
Between the power circuit, including circuits equivalent to this circuit and all other externally accessible circuits. Measure the insulation resistance after applying a 500V DC voltage for 5 hours.
The measurement results should comply with the provisions of Article 4.2.4a. 5.11.2 Withstand voltage test
During the test, the applied voltage should not exceed half of the full value of the test voltage, then quickly increase to the full value and maintain for 1 minute, then quickly decrease to below half the value, and then disconnect the power supply. During the test, semiconductor devices that may be damaged due to the influence of the electric field can be open-circuited during the type test. Short-circuited or replaced with simulants. During the inspection test, if there are such devices in the circuit, the test voltage should be reduced to 1kV. The test results should comply with the provisions of Article 4.2.4b. 5.12 Drop test
Place the instrument on a smooth, hard and firm concrete floor or steel plate surface in the normal use position, with one of its bottom edges as the axis, so that the distance between its opposite side and the test surface is 25mm, or the bottom surface and the test surface form an angle of 30°. A less stringent condition can be selected, and then the instrument is allowed to fall freely on the test surface. The four bottom edges of the instrument are used as axes and each is subjected to a drop. When the instrument falls, it is not allowed to overturn so that the adjacent surface of the test surface touches the ground. The test results should comply with the provisions of Article 4.6.
5.13 Grounding inspection
Inspect by visual inspection and the following methods
When measuring the resistance between the accessible metal parts and the protective grounding terminal, a 25A single-phase AC should be passed, and the voltage drop across the resistor should not exceed 12.5V. At this time, the corresponding resistance value is 0.5α. The inspection result should comply with the provisions of Article 4.2.6.
5.14 Internal structure and circuit inspection
Inspect by visual inspection or manual test.
Inspection result should comply with the provisions of Article 4.2.6.
5.15 Power supply connection inspection
Inspect by visual inspection, manual test and measuring tool
Inspection result should comply with the provisions of Article 4.2.8.
Inspection rules
JB/T7083-93
6.1Each impulse voltage tester must be tested and qualified by the quality inspection department according to the provisions of this standard before leaving the factory, and documents proving the product's qualification should be attached when leaving the factory.
6.2The items specified in this standard are type test items, and the items marked with * are factory inspection test items. Appearance inspection*
Electric shock protection inspection*
Impact voltage waveform parameter measurement*
Peak voltage error measurement*
Storage time measurement*
Load test*
Output short circuit test*
Anti-interference test*
Leakage current measurement
Insulation resistance measurement*
Withstand voltage test (only 4.2.4a and b are performed before leaving the factory)*Strength test of machine
Grounding inspection*
Internal structure and circuit inspection
Power connection inspection
Creep distance and electrical room inspection
6.3 Inspection method
Impact voltage tester Before the test, the instrument should be powered on at rated voltage for no less than 5 minutes. 6.3.1
The test is carried out on a prototype in the order specified in Article 6.2, and all tests should pass. Type tests shall be conducted for any of the following situations. When the trial production of a new product is completed;
When the changes in design or process are sufficient to cause changes in some of its performance, relevant type test items shall be conducted; when the inspection test results show an unacceptable deviation from the previous type test results; regular sampling of products.
Marking, packaging, transportation, storage
The impulse voltage tester shall be marked with the following items: a.
Product name (impact voltage tester);
Product model;
Rated output impulse voltage;
Maximum output impulse energy;
Manufacturer name or trademark;
Factory number.
JB/T7083-93
7.2 Each impulse voltage tester shall be accompanied by the following documents when it leaves the factory: 7.2.1Product certificate
Operation and maintenance instructions.
The manual should explain the following contents:
The principle, characteristics and uses of the impulse voltage tester should be explained separately; there should be an independent chapter to explain the safety precautions for the use of the instrument, possible dangers and corresponding preventive measures. b.
Maintenance matters related to the instrument.
7.3 The packaging, transportation and storage of impulse voltage testers shall comply with relevant regulations. Warranty period and spare parts, accessories
If the impulse voltage tester is damaged or cannot work properly due to poor manufacturing quality within one year from the date of manufacture, and within six months from the date of purchase, the manufacturer shall repair it for the user free of charge. Additional remarks:
This standard was proposed and coordinated by the Shanghai Electric Tool Research Institute of the Ministry of Machinery Industry. This standard was drafted by the Shanghai Electric Tool Research Institute and the Xi'an High Voltage Electric Appliance Research Institute. The main drafters of this standard are Liu Shunkong and Xu Yaojiang. 30
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