Lighting override control + Emergency Ballast.


Senior Member
I have a project that is on a very minimal budget but still needs to comply with my local state energy code. The project is similar to an office where there are several small rooms and a corridor that snakes through the building.

I am using occupancy sensors in the small rooms for local lighting control and I have chain hung fluorescents in the corridor wired to ONE circuit. The chain hung fixtures are all equipped with a battery backup ballast for emergency lighting.

These corridor fixtures will be controlled by a time clock but I need to incorporate (2) over-ride switches that will reset the time clock for 3 hours should someone be in there later then normal operating hours.

What is the simplest ( cheapest) way to accomplish this arrangement?

mopowr steve

Senior Member
Do you have a constant hot feeding the emergency ballasts so that they don't try to illuminate under battery power when time clock shuts off circuit?

mopowr steve

Senior Member
How about a motion sense switch(s) in parallel with time clock? Set time clock for approx 3 hours before closing time so that lighting is then taken over by motion sense and set motion time for 3 hours or whatever would seem appropriate, I would think maybe an hour would suffice. Would there be enough foot traffic in hall at end of day to allow this to work well?
Or just get rid of time clock alltogether and just use motion sense switches.


Senior Member
ET90215C is under $400.
It does say it has inputs for remote overrides, but it doesn't say what the override does. Does it turn on the output until you turn the switch back off? Or is it a momentary input with a timed override?

To comply with the energy code, I believe an override switch is limited to 2 hours. The 3 hour override the OP mentioned would probably not be compliant, and a maintained switch that has to be turned back off would not comply.


Use a momentary switch for the override. Set the override time to 2 hours. The override is an "on only" override, e.g. hitting the switch again does not toggle it back off. If you want a switch that turns it on/off and has the capability for override as well, you should look at a small relay panel.