Emergency lighting system with automatic diagnostic test
View Patent ↗An emergency lighting system powers all the luminaires of a lighting system during normal use, and switches from utility power to an emergency power source to drive some of the luminaires during a power outage. The typical on/off wall switch control for regular use carries out an automatic system test routine every time it is switched off. First, the non-emergency luminaires are extinguished, the emergency luminaires are activated for a time-limited period, and the system reverts to regular utility power and on/off control by the wall switch.
1. An emergency lighting system for powering at least one lighting fixture with regular utility power and at least one emergency lighting fixture when regular utility power is interrupted, including:
relay contact means for connecting emergency operating power to the at least one emergency lighting fixture in response to power failure in the regular utility power;
said regular utility power including a switch leg connected to the at least one lighting fixture, and further including means for detecting a transition from a switched on to a switched off condition on said switch leg and in response actuating said relay contact means to disconnect the regular utility power from the at least one emergency lighting fixture, and connect said emergency power source to the at least one emergency lighting fixture for a brief test period.
2. The emergency lighting system of claim 1 , further including wall switch means connected between a hot leg of the regular utility power and said switch leg to control the switched on and switched off condition of said switch leg.
3. The emergency lighting system of claim 2 , wherein after said brief test period said relay contact means reconnect the regular utility power to be available to the at least one regular lighting fixture and disconnect said emergency power source to the at least one emergency lighting fixture, whereafter the system is returned to operating on regular utility power in a switched off condition.
4. The emergency lighting system of claim 1 , further including an electronic assembly for combining and supporting said means for detecting a transition, and said relay contact means, and said sensing means.
5. The emergency lighting system of claim 4 , wherein said electronic assembly is installable in one of said at least one lighting fixtures.
6. The emergency lighting system of claim 4 , wherein said electronic assembly is installable in a typical junction box.
7. The emergency lighting system of claim 2 , further including an electronic assembly for combining and supporting said means for detecting a transition, and said relay contact means, said electronic assembly being installable in a junction box housing said wall switch means.
8. The emergency lighting system of claim 1 , wherein said relay contact means comprises normally closed relay contacts connected between an emergency hot supply and an emergency switching leg connected to the at least one emergency lighting fixture.