An unbalanced line is generally a single-conductor shielded cable with the center conductor carrying the signal and the shield at ground potential.
对于非平衡式信号线来说，就是一根被屏蔽了的信号线，这个中心信号线传输信号，且相对于地电势。
2
The signal injection method is widely used for automatic selecting fault line in indirectly earthed power system, which has great effect in the system of single-phase ground fault.
注入信号法是一种效果较好的选线方法，其原理广泛应用于小电流接地系统单相接地故障的自动选线。
3
On account of the weak fault current and unstable fault arc, the problems of the single phase to ground fault line selection in the non-solid earthed network have never been thoroughly resolved.