Input interface unit for programmable logic controller
US4381456A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 1981 |
| Grant date | Apr 26, 1983 |
| Priority date | — |
| Expiry date | Mar 19, 2001 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D10/00
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
The input interface unit of the present invention is equipped with plural input terminals to be connected to external switches respectively, plural output terminals to be connected to input bus lines running to a central control unit (CPU), and plural current-controlling input terminals. These input terminals are divided into plural groups, and the input terminals in each group are connected commonly to each other through pull-down resistors, and then connected through current-carrying switches independently grouped for each terminal group to a power supply equipment built in the unit. And each of these current-carrying switches can be selected and turned on or off for control in response to signals supplied from the central control unit to the current-controlling input terminals.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.