Method and apparatus for measuring current, especially useful in multi-ampere systems
US4186339A · kind A · utility
30Cited by
8References
13Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 20, 1978 |
| Grant date | Jan 29, 1980 |
| Priority date | — |
| Expiry date | Jan 20, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R1/203
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The disclosed method and apparatus make three connections to a pair of conductors: two at spaced-apart points on one conductor and the third on the other conductor. Using the power available in the conductors, a differential amplifier produces an output signal representative of current flow through the first conductor by sensing the voltage difference between the first and second connections to the first conductor. Temperature-induced changes in the resistance of the first conductor are compensated by a thermistor. The output signal is used to drive one or more displays of amperes, ampere-hours or watt-hours.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.