In the field of power equipment, electronic components, and new material research and development, the performance of insulation materials directly determines the safety and reliability of products. The DC breakdown voltage tester, as the core equipment for detecting the ultimate withstand voltage capability of insulation materials, provides key data support for material selection, process optimization, and safety certification by simulating the breakdown process under extreme voltage environment.

1、 Core principle: dynamic tracking from electric field polarization to insulation failure

The DC breakdown voltage tester is based on the principle of "dielectric strength testing", and applies a continuously boosted DC electric field to the insulation material through a high-voltage generator. When the electric field strength exceeds the inherent breakdown threshold of the material, polarization, sudden changes in conductivity, and partial discharge occur inside the insulating medium, ultimately leading to irreversible insulation failure. During the testing process, the instrument uniformly boosts the voltage at a rate of 0.1kV/s to 10kV/s, synchronously monitors the current mutation signal, and accurately captures the voltage peak at the moment of breakdown.

2、 Application scenarios of DC breakdown voltage tester: full chain coverage from laboratory to industrialization

Material research and development: In the development of new energy vehicle battery separators, testers can evaluate the breakdown voltage of different substrates, optimize separator thickness and coating processes.

Quality inspection: In the production of power transformers, insulation cardboard is subjected to breakdown testing to ensure that its withstand voltage value meets the GB/T 19001 standard.

Failure analysis: In the troubleshooting of aviation electronic equipment, the tester can locate the breakdown point caused by insulation material aging.

3、 Choosing a DC breakdown voltage tester requires comprehensive consideration of three factors:

1. Voltage range: Calculate the breakdown voltage value based on the sample thickness and standard requirements, and reserve a margin of 10-20kV. For example, when testing 2mm thick epoxy resin boards, if the standard requires a dielectric strength of ≥ 20kV/mm, equipment with a range of ≥ 50kV needs to be selected.

2. Power capacity: When the testing standard has clear requirements for current, attention should be paid to the transformer capacity. For example, when testing high capacitance samples, equipment with a power of ≥ 5kVA should be selected to avoid voltage drops.

3. Testing environment: Air medium testing is suitable for conventional materials, while oil medium testing is used for scenarios such as high-voltage cables. For example, 25 # transformer oil can eliminate air discharge interference and improve test repeatability.