Sunday, September 11, 2022
过流保护的类型有()。A、切断保护B、限流保护C、限流-切断保护D、电子保护...
Tuesday, April 16, 2024
Saturday, September 17, 2022
计算题:某电容接在频率为50Hz、电压220V电源上时,通过的电流为7A,求该电容多大?...
Sunday, July 30, 2023
Saturday, September 17, 2022
简述更换高频开关电源系统C级防雷单元的压敏电阻的好坏判断方法及更...
Saturday, September 17, 2022
Saturday, September 17, 2022
Saturday, September 17, 2022
低压电气设备停电后,用试电笔验电时,氖泡不亮就肯定无电。...
Saturday, September 17, 2022
Saturday, September 17, 2022
中间继电器有()副动静合触头。A、2B、3C、4D、5...
Sunday, May 5, 2024
Saturday, September 17, 2022
Saturday, September 17, 2022
Saturday, September 17, 2022
通信防雷系统要求()测一次接地电阻。A、1年B、6个月C、3个月D、1个月...
Wednesday, May 3, 2023
Saturday, September 17, 2022
Thursday, February 22, 2024
供油系统油箱的存油量一般应保持在其容积的()以上。A、1/3B、2/3C、1/2D、1/5...
Sunday, October 8, 2023
Saturday, September 17, 2022
Saturday, September 17, 2022