Emergency lighting system with a DC sensing load relay
US5859499A · kind A · utility
15Cited by
3References
12Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jan 15, 1997 |
| Grant date | Jan 12, 1999 |
| Priority date | — |
| Expiry date | Jan 15, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02J9/06
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An emergency lighting system has emergency light units operable by DC power and connected to a source of AC and DC power by the same conduit system. Power to the conduit system may be switched from AC to DC in the event of a power failure and a load relay module in the conduit system adjacent the light units senses the change to DC current and switches from an Ac load output to a DC load output to supply DC power to the emergency light units. The system will generally include both exit signs operable by both AC and DC power and emergency light units operable only by DC power.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.