正确设置TN系统中性线上的开关
Correctly Setting the Switch on Neutral Line of TN System
LO测量线上的开关总是和HI测量线上的开关处于相同状态(开路或闭合)。
The switch in the LO lead is always in the same state ( open or closed ) as the HI lead .
生产线上的开关故障诊断系统
Switch Trouble Diagnostic System in a Production Line