Device for monitoring short circuits and overloads in electronic proximity switches
US4795980A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 10, 1985 |
| Grant date | Jan 3, 1989 |
| Priority date | — |
| Expiry date | Dec 10, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/06
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A device for monitoring short circuits and overloads in electronic proximity switches of a transmission line. The device is a testing circuit which includes a current pickup which measures the current in the output circuit of a respective proximity switch which controls the output current flow by switching off or limiting the output current flow. The device also includes a circuit which provides a testing cycle for the current measurement with first and second delay times which control the output current during a short circuit or overload and a waiting time, substantially longer than the first delay time, between the start of two successive delay times. The length of the first delay time is chosen with respect to the time constant of the respective transmission line to be connected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.