公开(公告)号：US07791351B2

公开(公告)日：2010-09-07

申请号：US11889088

申请日：2007-08-09

Applicant: Monte B Raber

Inventor： Monte B Raber

IPC: G01R31/14 ,  H02H3/00 ,  H02H9/08

CPC classification number: G01R31/025

Abstract: A method of testing live AC circuits for neutral-ground, neutral-isolated ground, and isolated ground-ground faults, involves measuring impedances of circuit portions, including hot-neutral, neutral-ground, neutral-ground and isolated ground loops. In general either a test current generating a driving voltage is used, or in the case of hot-neutral, a load current generating a load voltage, and the voltage without current are use to measure voltage drop. These voltages are proportionate to the impedances of the circuits, which are expressed as ratios indicating the presence of faults. The method is reliable, despite much variation in circuit characteristics, including oversized neutral, shared neutral same phase, shared neutral opposed phase, supply line impedance, and high impedance grounds, it is easily able to detect faults across conductors and shared neutral loads.

Abstract translation: 测试中性点，中性线隔离地和隔离接地故障的实时交流电路的方法包括测量电路部分的阻抗，包括热中性线，中性线，中性线和隔离的接地回路。 通常，使用产生驱动电压的测试电流，或者在热中性的情况下，产生负载电压的负载电流，并且使用没有电流的电压来测量电压降。 这些电压与电路的阻抗成比例，其表示为指示故障存在的比率。 该方法是可靠的，尽管电路特性有很大的变化，包括过零中性点，共享中性相同相位，共享中性相对相位，电源线路阻抗和高阻抗接地，但是它能够很容易地检测导体和共享中性负载之间的故障。