Voltage protection circuit
US4027202A · kind A · utility
8Cited by
4References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1975 |
| Grant date | May 31, 1977 |
| Priority date | — |
| Expiry date | Dec 19, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H7/09
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
In a protection circuit for a device such as a motor, the unused half or a dedicated half of an AC signal on the secondary of an isolation transformer is sensed to disconnect the AC line from the device if the line voltage is abnormal, such as being too low. Conveniently the protection circuit is employed in a complete motor protection system which may include a thermal protection circuit, a low oil pressure protection circuit, and/or a time delay circuit to prevent start-up too soon after shut-down.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.