Circuit for measuring voltages in a three-phase installation, in particular an installation of the metalclad type
US4943765A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 31, 1989 |
| Grant date | Jul 24, 1990 |
| Priority date | — |
| Expiry date | Aug 31, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R15/06
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A circuit for measuring voltages in a three-phase installation, in particular an installation of the metalclad type, the circuit including for each of the phase conductors: a capacitive divider including a first capacitor connected firstly to said conductor and secondly to a second capacitor (C1, C2, C3) connected to ground, the circuit being characterized in that the voltage (v1, v2, v3) of each of the second capacitors (C'1, C'2, C'3) of the dividers is respectively applied firstly to the input of an inverter (I1, I2, I3) and secondly via a first resistance (R1, R2, R3) to the negative input of an operation amplifier (A1, A2, A3) which is also connected via second and third resistances (R21, R12, R13, and R31, R32, R23).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.