(NJ) Whole Building Generator - Emergency Lighting

[Strathead]

We had an inspector fail us for a particular situation and I'm trying to find the code reference as they neglected to site it. The inspector is an absolute hard-a$$ and while I believe this is a design issue, I'm inclined to not bother the guy because he's that bad.
The building has a back-up generator that essentially serves all of the loads, even the normal lighting. The inspector said that if the utility source is gone and the building is on generator, all emergency & egress lighting must be lit. The only way the lighting control system can determine that there's an issue is when the UL924 devices sense a loss of "normal" power. Since the normal power for lighting is backed up by a generator, it doesn't "know" it's in an emergency condition. The issue arose in areas that have emergency lights but may be locally switched off because of one or another (no occupancy, timed out, turned off on purpose, etc.). The AHJ wants all emergency lighting on in every area, regardless of occupancy, in the event of primary source loss and the generator turning on because it is an emergency situation.
I've been trying to find specific code references for this but I can't seem to find anything definitive. How would you achieve it after the lighting system has been installed, programmed, etc.? We installed it as designed so if we spend any money doing this, it's going to be a CO. I just would like a little NEC code help here if it has to go that far.

What is said. I agree, this is a HUGE design issue, unless the original design called for batteries in the emergency lighting, and that was VE'd out, then the error would be questionable.

 

[infinity]

Only the loads specified in the building codes can be on emergency circuits and those circuits must be completely separate from all other circuits. It the Article 700 generator supplies loads other than Article 700 loads, additional transfer switches are required.

I agree but what if the building doesn't actually require a generator?

 

[d0nut]

I agree but what if the building doesn't actually require a generator?

The building would most likely still require emergency egress lighting. The emergency egress lighting could be fed from an emergency generator, a lighting inverter, local battery backup, unit equipment, etc. If you provide the emergency egress lighting through something other than a generator, then the generator you provide would be an optional standby generator and not an emergency generator and not have the same requirements.

 

[Strathead]

The building would most likely still require emergency egress lighting. The emergency egress lighting could be fed from an emergency generator, a lighting inverter, local battery backup, unit equipment, etc. If you provide the emergency egress lighting through something other than a generator, then the generator you provide would be an optional standby generator and not an emergency generator and not have the same requirements.

Right, but the emergency light circuits still have the separation requirements.

 

[hillbilly1]

They don't but I don't believe it would matter if it did. If all of the lighting in the building is backed up by an emergency generator, then it wouldn't know the difference between utility or backup power.

There’s the problem, the generator cannot be classified as an emergency generator because it supplies the whole building, it is an optional standby system, unless a separate transferswitch powers the emergency lights. If a second generator, or battery backup is present, then the main generator would be irrelevant, and treated as another utility source. The inspector is correct.

 

[ron]

If it is a breaker trip on the normal lighting side, your EM panel will still have power from the normal side of the ATS and there is no need to start the generator. If it is a breaker trip on the EM panel side, the normal lighting in the area will still have power and allow a safe egress from the building. This is why two sources of power (normal and emergency) are required for egress lighting in an egress path. You can lose either one, but not both, and will still be able to egress in the light.

My concern is a breaker trip downstream of the ATS. No normal or EM power for potentially many 1000's of square feet of egress path.

 

[gadfly56]

My concern is a breaker trip downstream of the ATS. No normal or EM power for potentially many 1000's of square feet of egress path.

I agree. Battery backup is the simplest, most fool-proof way to provide emergency lighting in an occupancy for emergency egress lighting. Anything else is going to require thousands of dollars of installation labor and control equipment, and it still requires testing once or twice a year. Just hire your local fire protection company to do it while they are checking your fire extinguishers. For the cost of the complicated solution, you can get a lot of years, if not a couple of decades, of inspection.