Control circuit
US4090121A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 1976 |
| Grant date | May 16, 1978 |
| Priority date | — |
| Expiry date | Sep 9, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG05B13/024
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A process controller which has at least a derivative control mode includes a comparison amplifier wherein a measured variable signal is compared with a set-point signal to produce an error signal. An auxiliary control circuit including a signal level change detector is connected to detect changes in the set-point signal. During intervals of constant set-point signal, the primary control circuit operates normally. Upon the occurrence of a change in the set-point signal, the change is detected by the auxiliary control circuit and produces an auxiliary control signal which is applied to momentarily inhibit the operation of the derivative control function of the controller.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.