Sikaolin has collaborated with many domestic laboratories that have been internationally recognized by CNAS (China National Accreditation Service for Conformity Assessment) or ILAC.
International standards: IEC 60060 (High Voltage Test techniques), IEC 61083 (High Voltage Test instruments and software), etc.
National standards: such as GB/T 16927 (Chinese High Voltage Test Standard), JJG (Metrological Verification Regulation), etc.
Industry norms: Requirements for the power industry (such as DL/T 474) and laboratory certification (such as ISO/IEC 17025).
Main verification items
(1) Basic parameter verification
Voltage measurement system (voltage divider, measurement winding) :
Ratio error (such as within ±1%), linearity, frequency response.
Square wave response (crucial for impact test equipment).
Current measurement system (Rogowner coil, shunt) :
Ratio error, phase difference, dynamic characteristics.
Time parameter (impact generator) :
The accuracy of wavefront time (T1) and half-peak time (T2).
(2) Insulation performance test
Withstand voltage test: power frequency withstand voltage, DC withstand voltage or impulse withstand voltage, to verify the insulation strength of the equipment.
Partial discharge detection: Verify the partial discharge capacity of the equipment under high voltage (such as ≤10pC).
(3) Function and safety verification
Protection device testing: overcurrent protection, grounding interlock, emergency stop function.
Environmental tests: Temperature and humidity influence, electromagnetic compatibility (EMC) testing.
Verification method
Standard source method: Use a higher-precision standard voltage/current source (such as a standard voltage divider, calibrator) to compare the output of the device under test.
Comparison method: Measure the same signal synchronously with the calibrated reference device and analyze the deviation.
Simulated load testing: Verify the load-carrying capacity of the equipment (such as high-current generators) by simulating actual loads.
Verification cycle
Regular calibration: Usually once every 1-2 years (depending on the frequency of use and standard requirements).
Temporary verification
After equipment maintenance or replacement of key components.
Abnormal conditions (such as abnormal test results, overload impact).
Verification institutions and reports
Authoritative institutions: Laboratories that have passed the international mutual recognition of CNAS (China National Conformity Assessment Committee) or ILAC.
Report content:
Equipment information, calibration standards, test data, uncertainty analysis, conclusions and validity periods.
Verify the core purpose
Accuracy verification: Ensure that the voltage/current measurement error is within the standard range (such as ±1%).
Safety assurance: Verify insulation strength and the reliability of protection devices.
Compliance confirmation: Meet the requirements of standards such as IEC, GB, and DL.
The standard for verification basis
International standards: IEC 60060 (High Voltage Test techniques), IEC 61083 (High Voltage Test instruments and software), etc.
National standards: such as GB/T 16927 (Chinese High Voltage Test Standard), JJG (Metrological Verification Regulation), etc.
Industry norms: Requirements for the power industry (such as DL/T 474) and laboratory certification (such as ISO/IEC 17025).
Main verification items
(1) Basic parameter verification
Voltage measurement system (voltage divider, measurement winding) :
Ratio error (such as within ±1%), linearity, frequency response.
Square wave response (crucial for impact test equipment).
Current measurement system (Rogowner coil, shunt) :
Ratio error, phase difference, dynamic characteristics.
Time parameter (impact generator) :
The accuracy of wavefront time (T1) and half-peak time (T2).
(2) Insulation performance test
Withstand voltage test: power frequency withstand voltage, DC withstand voltage or impulse withstand voltage, to verify the insulation strength of the equipment.
Partial discharge detection: Verify the partial discharge capacity of the equipment under high voltage (such as ≤10pC).
(3) Function and safety verification
Protection device testing: overcurrent protection, grounding interlock, emergency stop function.
Environmental tests: Temperature and humidity influence, electromagnetic compatibility (EMC) testing.
Verification method
Standard source method: Use a higher-precision standard voltage/current source (such as a standard voltage divider, calibrator) to
compare the output of the device under test.
Comparison method: Measure the same signal synchronously with the calibrated reference device and analyze the deviation.
Simulated load testing: Verify the load-carrying capacity of the equipment (such as high-current generators) by simulating actual loads.
Verification cycle
Regular calibration: Usually once every 1-2 years (depending on the frequency of use and standard requirements).
Temporary verification
After equipment maintenance or replacement of key components.
Abnormal conditions (such as abnormal test results, overload impact).
Verification institutions and reports
Authoritative institutions: Laboratories that have passed the international mutual recognition of CNAS (China National Conformity Assessment Committee) or ILAC.
Report content:
Equipment information, calibration standards, test data, uncertainty analysis, conclusions and validity periods.
Verify the core purpose
Accuracy verification: Ensure that the voltage/current measurement error is within the standard range (such as ±1%).
Safety assurance: Verify insulation strength and the reliability of protection devices.
Compliance confirmation: Meet the requirements of standards such as IEC, GB, and DL.
Verify object classification
Power frequency high-voltage equipment: power frequency withstand voltage device, test transformer
Dc high-voltage equipment: DC generator, pulse breakdown device
Impulse voltage equipment: lightning/operating impulse generator, voltage divider
Partial discharge equipment: PD detector, calibration pulse generator
Auxiliary systems: Ground resistance tester, shielding room efficiency
Key verification items and methods
1.Calibration of the voltage measurement system
Voltage divider calibration
Standard method: Use a standard voltage divider (uncertainty ≤0.5%) for comparison, and input step voltages to verify the linearity.
Frequency response: Check the amplitude-frequency/phase-frequency characteristics by scanning the frequency signal (such as 10Hz-1MHz).
Oscilloscope channel: Calibrate the vertical gain and time base accuracy (refer to JJG 262).
2. Calibration of the current measurement system
Roche coil/shunt
Ratio error: Inject standard current (such as 10A-100kA) and compare the readings.
Step response: Evaluating dynamic characteristics (critical for inrush current).
3. Waveform parameter verification (Impact equipment)
Lightning shock wave (1.2/50μs) :
Wavefront time (T1) tolerance: ±30%
Half-peak time (T2) tolerance: ±20%
Operating shock wave (250/2500μs) : Verify the attenuation characteristics of the long wave tail.
4. Insulation and safety testing
Power frequency withstand voltage test: 1.1 times the rated voltage for 1 minute, no flashover/breakdown.
Partial discharge quantity: Background noise ≤5pC. Verify the sensitivity by calibrating the pulse injection method.