Contact on test switch
US4880395A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 9, 1988 |
| Grant date | Nov 14, 1989 |
| Priority date | — |
| Expiry date | Dec 9, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S439/912
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
The present invention relates to a test system for a protective relay. The test system comprises a test switch (1) and a test-plug handle (2). The invention comprises supplementing the system with a contact function which is activated when the handle is inserted into the test switch so that, before the testing of the relays in the protective device is initiated, a signal function can be obtained to indicate that testing is in progress. The contact function is brought about by arranging, on the upper and/or lower side(s) of the test switch, two semi-protected, uninsulated and parallel contact pins/slide bars (4, 5) from the front edge to the rear edge of the test switch. At the rear edge contact parts to ordinary conductors are arranged in order to forward the contact function. The contact pins are mounted in a guide structure (10, 11) formed with an inner guide profile adapted to guide two resilient tongues (13, 14) on the test-plug handle. On the sides of the tongues facing the test switch, these tongues are each provided with a contact washer. The parts included cooperate in such a way that, once the test-plug handle has been inserted into the test switch, contact is achieved bet…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.