Correction of a pressure indication in a pressure transducer due to variations of an environmental condition
US5329818A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 28, 1992 |
| Grant date | Jul 19, 1994 |
| Priority date | — |
| Expiry date | May 28, 2012 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L19/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A two-wire transmitter includes a pressure sensor comprising first and second sensing means each having an impedance value which varies with pressure being measured and with a predetermined environmental condition, such as line pressure or temperature. A fixed impedance has an impedance value which is substantially unchanged by variations in the predetermined environmental condition. A switch alternately connects the fixed impedance into operative relation with the first and second sensing means to derive first and second signals which are each functions of pressure being measured and the predetermined environmental condition. A correction circuit processes the first and second signals, such as by a polynomial series or with a lookup table, to derive a corrected pressure signal. In one form, the sensor senses differential pressure and the predetermined environmental condition is line pressure or temperature, and the first and second signals are functions of both differential pressure and either line pressure or temperature, so the correction circuit derives an indication of differential pressure corrected for variations in either line pressure or temperature. In another form, the s…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.