Combined input/output circuit for a programmable controller
US4951250A · kind A · utility
Inventors
Key dates
| Filing date | Nov 18, 1988 |
| Grant date | Aug 21, 1990 |
| Priority date | — |
| Expiry date | Nov 18, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B2219/1157
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A combined input/output circuit is provided which is configurable either as in input circuit or an output circuit for use in a programmable controller. The input/output circuit includes apparatus which detects undesired overcurrent and overvoltage external conditions and adaptively protects itself from such conditions. The circuit includes a sensing circuit which is capable of sensing overcurrent conditions and detecting input data depending on the configuration of the input/output circuit. The inherent characteristics of a switching device used to configure the circuit in either an input or output state are used to detect overcurrent and to limit fault current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.