Hall-effect current clamp
US4704575A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 11, 1986 |
| Grant date | Nov 3, 1987 |
| Priority date | — |
| Expiry date | Apr 11, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01R15/202
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A Hall-effect current clamp, in which the constant-current generator (13) supplying the Hall-effect cell (8) comprises an operational amplifier (15) which has an internal-voltage reference (17) and which pilots a transistor (Q1) mounted in emitter follower in series with the cell (8), such that the current which traverses it is on the order of 1 mA. At the output of the measurement amplifier (14) of the clamp, a dividing bridge (P1,R5) whose intermediate lead is connected to the inverting (-) input of the amplifier (14) permits obtaining a supplementary amplification of the output signal of the clamp at the price of a low current consumption. Thus, the total current consumption of the clamp is maintained at a very low level, thereby providing a considerable increase in the life span of the batteries (9) used to supply the clamp.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.