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Emergency lighting units on standby generator

Emergency lighting units on standby generator

Emergency lighting units on standby generator


I wanted to inquire if battery powered emergency lighting units could be connected to standby generator circuit for application described as follows:

1. Emergency lights stay OFF during normal power and its batteries are charged.

2. In an event of a power outage, the emergency lights come ON, and the batteries are charged by the standby generator.

3. In the standby generator fails for some reason, the batteries would keep the emergency lights ON.

Thank you.

RE: Emergency lighting units on standby generator

It would ultimately depend in the applicable requirements for your application.

In my workplace, the backup generator powers some normal ceiling light fixtures. I believe that the battery powered emergency lights are off when the generator is on. So the emergency lights must be powered from a bus that has the generator as the backup.

Your requirements may vary. Was this on a ship?

RE: Emergency lighting units on standby generator

Theoretically, yes. The devil, as always, is in the details. You need to have a light unit that can tell the difference between regular power and generator power, either through analyzing the power itself, or through a secondary mechanism.

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RE: Emergency lighting units on standby generator

Thank you for the responses.

The application is for a 2 storey multi-unit residential building. If some of the ceiling lights are on the generator and if they are located in the corridors/stairwells/exits then they may constitute as "Emergency Lighting" because the self-contained battery powered emergency lighting units that are now backed up by generated would not turn ON during a power outage until the generator fails, because their batteries would be in charging mode when they receive standby power from the generator.

RE: Emergency lighting units on standby generator

Sidestepping a bit... does this all really matter?

If the lights are powered, does it really matter if power comes from the power company or a backup generator? The backup lights are supposed to work if power is lost to the main lights... if the backup and main lights are on the same circuit, the backup lights kick in when main power is lost. "Main power", in this case, is both PoCo and genny giving up the ghost.

I feel like we're trying to solve a problem that shouldn't exist n the first place... or I'm severely misunderstanding the issue.

Dan - Owner

RE: Emergency lighting units on standby generator

That's exactly what I'm saying, IR... it's pointless to have backups running if a generator is applying power to the regular lights. Put backup and regular lights on the sam circuit, therefore, the backups only turn on when ALL power is lost (main and generator). To do otherwise seems pointlessly complicated.

Dan - Owner

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