Device for checking the operability of a sensor element
US8330470B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 2008 |
| Grant date | Dec 11, 2012 |
| Priority date | — |
| Expiry date | Mar 16, 2029 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/419
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
The invention relates to a device for checking the operability of a sensor element (100) for determining the concentration of gas components in a gas mixture, particularly of the concentration of gas components in the exhaust gas of internal combustion engine, having an external pump electrode (APE) and an internal pump and Nernst electrode (IPE), a measurement resistor (Rm) and a balancing resistor (Rtrim) connected parallel thereto being provided upstream of the external pump electrode (APE), and a pump current (Ip) being impressible into the external pump electrode by means of a pump current source, and a measuring voltage (Um) incident across the measuring resistor (Rm) via a measuring and analysis device (200) being detectable, characterized in that an activatable switch means (S) is disposed in series to the measuring resistor (Rm), which can be switched at a high impedance for a predetermined amount of time, during which the voltage across the measuring resistor is detected and analyzed in the measuring and analysis device, and that an error output occurs upon a predetermined voltage threshold value being exceeded.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.