Method and electrical measuring apparatus for analyzing the impedance of the source of an actual alternating voltage
US5105181A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 17, 1990 |
| Grant date | Apr 14, 1992 |
| Priority date | — |
| Expiry date | Aug 17, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R27/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and an electrical measuring apparatus for analyzing an actual alternating voltage present on an electrical wire or electrical equipment whereby to determine if the voltage originates from a high or low impedance source for the safety of the operator. A bi-impedance probe is connected to the alternating voltage to be analyzed and the voltage signals are processed. The actual probe consists of a first series of uni-directional elements and a second parallel series of high value resistance elements. The output of the parallel connected series of elements is connected to a third series of low value resistance elements. A measuring circuit is connected to the third series of low value resistance elements and is capable of discriminating between the voltage signals from both of the series of resistive elements and is provided with a calculating circuit to determine if the voltage signals originate from a high or low impedance source. The output of the probe is connected to ground. An indicator indicates the condition of the impedance source. An alarm indicator may indicate if a predetermined threshold value, representative of a low impedance source, is exceeded.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.