Safety apparatus for detecting an abnormality of power control element
US4882782A · kind A · utility
13Cited by
11References
7Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 10, 1987 |
| Grant date | Nov 21, 1989 |
| Priority date | — |
| Expiry date | Sep 10, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H7/12
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A safety apparatus for an AC control circuit has a bidirectional thyristor, a photocoupler for detecting a load current, a transistor and a self-hold circuit for checking if a detection output from the photocoupler indicates a failure of the thyristor to commutate or lack of a trigger signal and another transistor which is turned on to blow a fuse and to cut off the load current when a failure of the thyristor to commutate or lack of the trigger signal is detected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.