智能电表用磁保持继电器失效原因及机理分析

Failure Cause and Mechanism of Magnetic Latching Relays for Smart Meters

磁保持继电器是智能电表的核心部件之一,应具有高的可靠性、安全性及抗短路电流能力。本文针对智能电表用磁保持继电器的常见失效原因进行了分析。结果表明,触头表面污染引起磁保持继电器熔焊失效;复合铆钉触头开裂导致磁保持继电器熔焊失效或断开失效;在进行短路载流能力试验时,不合理的磁保持继电器结构引发爆炸;中间位置导致磁保持继电器出现断开失效。

Magnetic latching relay is one of the core components of smart ammeters, and it is required to have high reliability, security and short-circuit current carrying capacity. The factors which are often seen causing the failure of magnetic latching relays are analyzed in this paper. Results show that contamination on the contact surface of magnetic latching relays may cause a welding failure. Cracks in bimetal contacts may cause the contacts unable to close or welding failure. Unreasonable structure of magnetic latching relays may cause an explosion during the test for short-circuit current carrying capacity. The occurrence of the neutral position may lead to operation failure.