Inrush current limiter in a magnetic flowmeter
US5436824A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 10, 1992 |
| Grant date | Jul 25, 1995 |
| Priority date | — |
| Expiry date | Dec 10, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S323/908
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An AC powered field mounted process control transmitter includes an inrush current limiter which prevents excessive current flow to other circuitry in the transmitter. The transmitter senses a physical parameter, such as flow, and comprises a source of current, a current driven sensing circuitry, the inrush current limiter and measurement electronics for converting the sensed parameter into a transmitter output. The limiter includes a reference voltage source and is in series between the current source and the current driven sensing circuitry. When inactive (i.e. not limiting current), the limiter responds to the series current through itself so that when such current exceeds a predetermined maximum level the limiter becomes active and prevents further current flow. The limiter remains active until the voltage across itself is less than the reference voltage, at which time the limiter becomes inactive.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.