Residual current detector with fail safe lockout device
US6324043A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Sep 28, 1999 |
| Grant date | Nov 27, 2001 |
| Priority date | — |
| Expiry date | Sep 28, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02H3/05
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
This invention provides a residual current detector comprising a trip circuit; a magnetic lock assembly including a solenoid that operates in response to a signal from the trip circuit, causing movement of an operating member, with the magnetic lock further including a reset mechanism for resetting the residual current detector following a trip operation; and means for preventing reset of the magnetic lock by restraining movement of the solenoid when the trip circuit is disabled. In the preferred embodiment, a plunger assembly is mounted adjacent to the solenoid of the magnetic lock assembly and fusible link is connected in series with the trip circuit and mounted to prevent movement of a plunger in the plunger assembly. When the trip circuit is subjected to excessive current, the fusible link will melt, thereby permitting the plunger to interfere with movement of the armature of the solenoid. This prevents rest of the magnetic lock assembly.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.