-
English
19
2022
-
09
What factors affect the change of insulation resistance
Category：
【Summary】Influence of temperature: temperature has a great influence on insulation resistance. Generally, insulation resistance decreases with the rise of temperature.
1. Effect of temperature: temperature has a great impact on insulation resistance. Generally, insulation resistance decreases with the rise of temperature. The reason is that when the temperature rises, the polarization in the insulating medium intensifies, which increases the conductivity and reduces the insulation resistance. It is also related to the degree of temperature change and the nature and structure of insulating materials. Therefore, the temperature must be recorded during measurement so that it can be converted to the same temperature for comparison.
2. Influence of humidity: the insulation surface absorbs moisture, which forms a water film on the surface of the porcelain bushing, often significantly reducing the insulation resistance. When the relative humidity in the air is high, it will absorb more moisture, which increases the conductivity, and also reduces the insulation resistance value.
3. Effect of discharge time: after each insulation measurement, the tested shall be fully discharged, and the discharge time shall be longer than the charging time, so as to drain the remaining charge. Otherwise, during the re-measurement, due to the influence of the charge, its charging current and absorption current will be smaller than the first measurement, resulting in the false phenomenon that the absorption specific insulation resistance value increases, which often occurs when testing cables.
4. Analysis and judgment: insulation of high-voltage electrical equipment with large capacitance, such as cables, transformers, generators, capacitors, etc. It is mainly based on the absorption ratio. If the absorption ratio is significantly reduced, it means that the insulation is affected by moisture or the oil quality is seriously degraded.
Related news
Milliohm Electronics' October 2026 Domestic Exhibition and November Overseas Exhibition Preview
Milliohm Electronics will participate in multiple power electronics and automotive electronics industry exhibitions and specialized technical exchanges with host factories in Shanghai, Chongqing, Xi'an, and other places in October, showcasing related supporting solutions such as alloy resistors, shunts, and automotive electronics solutions; The company is also deeply cultivating overseas markets and will debut at the electronica 2026 exhibition in Munich, Germany from November 10th to 13th (booth: B6-177), bringing a full range of resistor products and solutions to expand global cooperation. We sincerely invite colleagues from all walks of life to come and exchange ideas.
MORE +On September 18th, the 2026 Annual Meeting of the Electronic Components Equipment and Instrument Professional Committee of the China Electronic Components Industry Association was successfully held in Luoyang, Henan. This conference is an important parallel thematic activity of the 2026 China Electronic Components Industry Summit, gathering industry experts and backbone enterprises in the industry chain to discuss key issues such as equipment and instrument innovation and upgrading, domestic breakthroughs, and industry chain collaboration. Zheng Zhimin, General Manager of Shenzhen Milliohm Electronics Co., Ltd., was invited to attend the conference and explore the path of innovative development and localization upgrading in the precision resistor industry with industry colleagues.
MORE +Focusing on the innovation of intelligent chassis, empowering the upgrade of in vehicle electronic control! On September 20th and 21st, Milliohm Electronics made appearances at the SAIC Maxus and SAIC Shangjie Intelligent Chassis Innovation Technology Exhibition, connecting with cutting-edge vehicle research and development scenarios, and conducting face-to-face technical exchanges with automotive technology teams and industry colleagues. The two high-quality OEM special exchange activities came to a successful conclusion. At this exhibition, Milliohm Electronics showcased its main product matrix, including high-precision electron beam welding alloy resistors, automotive grade shunt, and busbars. The products cover two core application scenarios: low-voltage electronic control and high-voltage systems for vehicles, and can solve various current sampling difficulties and pain points in the development process of intelligent chassis.
MORE +From September 15th to 18th, the Gaishi Automotive 2026 Series Technology Forum was successfully held in Shanghai, focusing on cutting-edge fields such as intelligent automotive chips, in car AI, and intelligent perception, bringing together enterprises and experts from the entire industry chain to explore industry development trends. Milliohm Electronics has gathered teams from three regions to participate in the exhibition, showcasing its core automotive products and gaining widespread attention from the industry.
MORE +
Contact us
High-precision Resistance
Quality Provider
Follow us
Copyright © 2022 Shenzhen Milliohm Electronic Co.,Ltd Powered by www.300.cn Shenzhen SEO Business license