Insulating oil dielectric strength tester, also known as insulating oil withstand voltage tester or oil dielectric loss tester, is a specialized equipment used to evaluate the electrical insulation performance of insulating oil (mostly transformer oil), mainly for detecting the oil’s ability to withstand breakdown in an electric field environment, ensuring the safe operation of power equipment such as transformers, transformers, and oil circuit breakers.
Application scope
The insulating oil dielectric strength tester can be applied throughout the entire process of power system production, installation, maintenance, and research, and the specific applicable fields are as follows:
Electric power industry
Transformer manufacturing plants: Testing the insulation performance of new factory-produced transformer oil to control the quality of the products upon leaving the factory.
Power transmission and transformation and power supply companies: Conducting regular oil sample tests on operating transformers and oil switches to prevent insulation failure from causing flashover, short circuit, etc.
Various power plants: Including thermal power, hydropower, wind power, and nuclear power, regularly monitoring the aging of insulating oil in main transformers, plant transformers, and high-voltage reactors.
Petrochemical and refining industry
Used to evaluate the quality of base oil and regenerated oil, ensuring that the factory-produced insulating oil complies with relevant standards such as GB/T 507 and IEC 60156.
Railway and rail transit
Testing the insulation oil status of traction transformers and locomotive transformers to ensure the stable and reliable operation of the power traction system.
Large industrial enterprises
Covering metallurgy, chemical industry, mining and other industries, conducting regular oil withstand voltage tests on oil-immersed equipment in enterprise self-owned substations and large motors to avoid production losses caused by power interruption.
Research and teaching institutions
Used for conducting research on the characteristics of insulating materials in high-voltage technology laboratories or as experimental equipment for electrical engineering teaching in universities.
Selection method
When choosing an insulating oil dielectric strength tester, the following factors can be mainly referred to:
1. Testing standards
Domestic standards: If the domestic standards such as GB/T 507 are used as the detection basis, the equipment must meet the corresponding voltage rise rate (such as 2.0kV/s ± 0.2kV/s), static time, etc. requirements.
International standards: If it involves export equipment or follows IEC standards, it is necessary to confirm that the equipment supports international norms such as IEC 60156, and currently most equipment can achieve multi-standard switching.
2. Voltage level
0～60kV/80kV: General-purpose equipment, suitable for the insulation performance testing of most 10kV to 35kV transformer oil, commonly used in selection.
0～100kV/120kV: Suitable for 110kV, 220kV and above high-voltage, ultra-high-voltage equipment, or scenarios with strict insulation performance requirements.
Note: The voltage level of the equipment should match the tested equipment, and there is no need to blindly choose high-voltage models.
3. Automation level
Fully automatic type: The mainstream type, using microcomputer control, parameters set can automatically complete voltage rise, breakdown judgment, data recording and printing, with small test error and high work efficiency.
Single cup and multi-cup type:
Single cup type: Can only test one oil sample at a time, suitable for laboratories with less sample volume.
Three cup / six cup type: Can place multiple oil samples at a time and automatically test them in sequence, suitable for scenarios with large amounts of oil sample testing, and can effectively improve testing efficiency.
4. Oil cup structure and material
Electrode material: Mostly copper or stainless steel, the electrode spacing needs to meet the standard requirements (generally 2.5mm).
Capacity: The conventional oil cup capacity is approximately 500ml or 200ml, determined according to the corresponding standards.
Ease of cleaning: Preferably choose oil cups with convenient disassembly and easy cleaning to reduce sample cross-contamination risks.
5. Safety and protection functions
Zero start protection: The voltage regulator returns to zero before starting the voltage rise to avoid accidental operation.
Overcurrent / overvoltage protection: Can quickly cut off high voltage during breakdown to ensure the safety of the equipment and personnel. Grounding detection: Some devices can detect the grounding status. When the grounding is poor, the high voltage cannot be activated.
6. Data processing capabilities
Storage and printing: Pay attention to whether the device is equipped with a thermal printer and the historical data storage capacity.
Communication interfaces: You can choose devices with interfaces such as RS232, USB, Bluetooth, etc. according to your needs, which is convenient for uploading data to the management system or a computer for analysis.
Post time: Feb-26-2026