Content and Precautions of Spring Finger Contact

In various maintenance guides (procedures) and standards, there are regulations for measuring the contact clamping force of the contact finger. (Wuhan Qiji Electronics) recommends using a spring scale as the measuring tool. In practice, measuring the contact finger clamping force at high altitude with a spring scale is not only inconvenient and inaccurate but also ineffective. For some structural isolating switches, the contact finger clamping force cannot be measured at all with a spring scale.

Abstract: To address the overheating issue in the conductive circuit during the operation of high-voltage isolating switches, combined with the infrared temperature measurement discovery of the heating defect in the G4 type isolating switch, an analysis was conducted from the aspects of operating environment, switch structure, and operation and maintenance. It is believed that corrosion of the contact finger spring caused by rain and fog erosion leads to performance degradation. The contact finger spring being in a long-term tensile state causes a decrease in contact pressure and an increase in contact resistance, which is the fundamental cause of overheating. It is proposed to select contact finger springs made of high-quality stainless steel material with a structure of internal embedding and external pressure type isolating switch, as well as to strengthen installation supervision and operation maintenance. Zhen Xu. Analysis of heating failure of double-contact isolating switch in 500kV substation [J]. Electrical Technology, 2012. From the perspective of personalized medical device business, the company's medical sector has the advantage of nationwide layout and extensive terminal channel coverage in the orthopedic specialty field, with no significant fluctuations in customer demand. Currently, three R&D patents have been obtained: a utility model patent for a hole processing fixture of a Y-shaped bone plate; a utility model patent for a special storage box for bone needles; and a bending forming method for spiral spring contact fingers.