Exit Lights

[Tulsa Electrician]

With led now I have even installed an inverter based back up for pathway egress as well as the exits. The down side is maintenance with the system.

 

[Fryman]

It’s my opinion that exits signs that have battery backup do fall under the definition of “Unit Equipment” and are required to be wired per NEC 700.12(F)(2)(3) on the same circuit as the local normal area lighting. Unless you can qualify for the exception when 3 or more circuits serve an uninterrupted area. In which case you would have to lock the breaker per the exception. But with LED lighting these days, that is rare.

If the exit signs don’t have battery backup, they are not “Unit Equipment” and they will be wired to an inverter system or generator on a circuit separate from the normal lighting.

The goal is that they are on all the time, and they have backup power for at least 90 minutes if normal lighting power is lost in the space.

 

[don_resqcapt19]

I think this was an oversight by the code making panel that will probably be revised in a forthcoming NEC. NFPA 101 requires the emergency egress lighting to come on when the normal lighting in that space loses power. If you connect your unit equipment to a different circuit than the normal lighting, it would make meeting this requirement more difficult.

From the 2012 version of NFPA 101:
7.9.2.3 The emergency lighting system shall be arranged to provide the required illumination automatically in the event of any interruption of normal lighting due to any of the following:
(1) Failure of a public utility or other outside electrical power supply
(2) Opening of a circuit breaker or fuse
(3) Manual act(s), including accidental opening of a switch controlling normal lighting facilities

Admittedly, I have never had a good understanding of what exactly is required by item (3).

They rejected my PI to fix this so it is a very intentional change and not an oversight.

 

[don_resqcapt19]

It’s my opinion that exits signs that have battery backup do fall under the definition of “Unit Equipment” and are required to be wired per NEC 700.12(F)(2)(3) on the same circuit as the local normal area lighting. Unless you can qualify for the exception when 3 or more circuits serve an uninterrupted area. In which case you would have to lock the breaker per the exception. But with LED lighting these days, that is rare.

If the exit signs don’t have battery backup, they are not “Unit Equipment” and they will be wired to an inverter system or generator on a circuit separate from the normal lighting.

The goal is that they are on all the time, and they have backup power for at least 90 minutes if normal lighting power is lost in the space.

There is nothing to even suggest that an exit light provides illumination so there is no requirement that it be supplied by a circuit that supplies illumination in the area.

 

[Open Neutral]

I recall being in a secure room in a facility. There was a wide-area power failure.
The battery-fed lamps came on... until the building generator started, when they went out again.
We took turns holding down the TEST buttons while we secured all the classified data and locked all the containers.

I had to write a memo explaining that a) the room had no ceiling lamps on the emergency circuits, but b) the battery lamps were.

 

[don_resqcapt19]

I recall being in a secure room in a facility. There was a wide-area power failure.
The battery-fed lamps came on... until the building generator started, when they went out again.
We took turns holding down the TEST buttons while we secured all the classified data and locked all the containers.

I had to write a memo explaining that a) the room had no ceiling lamps on the emergency circuits, but b) the battery lamps were.

That was a very common design mistake that I have seen over the years.

 

[Open Neutral]

That was a very common design mistake that I have seen over the years.

Part of the issue was the room lighting had filters of some ilk to avoid leakage of anything classified via the power feed. So the Battle Lanterns should not have been on the emergency circuit anyhow. I'd assume they were present for that reason. (Do occupied spaces with generator-fed lighting need internal Battle Lanterns??)

 

[Fryman]

There is nothing to even suggest that an exit light provides illumination so there is no requirement that it be supplied by a circuit that supplies illumination in the area.

I'm not suggesting that an exit light provides illumination. Article 700.16 says that illuminated exit signs are part of the Emergency Illumination.

 

[don_resqcapt19]

I'm not suggesting that an exit light provides illumination. Article 700.16 says that illuminated exit signs are part of the Emergency Illumination.

If it does not supply area illumination, it is not required to be supplied by the branch circuit that supplies the normal illumination in the area. There is nothing to be gained by requiring the normal power to an exit light be supplied from the same circuit that supplies normal power to the area illumination.

 

[garbo]

According to section 700.12(F)(2)(3) of the 2017 NEC:

"The branch circuit feeding the unit equipment shall be the same branch circuit as that serving the normal lighting in the area and connected ahead of any local switches."

Any emergency lights, such as the wall mounted battery packs with the 2 bulbs, have to be connected to the normal lighting circuit in the area.

My question is, this does not include exit lights, correct? Can the exit lights be on their own circuit?

All emergency luminaries should be on the same circuit as the room luminaries. Years ago I worked at a large company and refused to handle exit luminaries replacement unless We rewired them. Engineer said they were within code and with a dual 13KV service seldom loose power. Exit luminaries were on cords and plugged into a 120 volt branch circuit while ceiling luminaries were on 277 circuits. Anyway we lost power to the 277/480 panel that feed ceiling luminaries during busy lunch time. We stayed overtime to wire the numerous wall packs that day.

 

[roger]

As to whether Exit Signs with battery backup are considered emergency units read UL Emergency Lighting and Power Equipment (FTBR)

They are listed under UL 924. Page 198 below.

https://code-authorities.ul.com/wp-content/uploads/2014/09/UL-White-Book.pdf

 

[Knightryder12]

I thought the rule was that all emergency lighting, including exit signs had to be powered from the same circuit in that area unless the area was large and required at least 3 lighting circuits. At that point the emergency lights could be fed from a separate circuit. I guess the thought process was that there would be no way all 3 normal lighting circuits could go out, if they did that would be a complete power outage and the emergency lights would come on.

 

[david luchini]

I thought the rule was that all emergency lighting, including exit signs had to be powered from the same circuit in that area unless the area was large and required at least 3 lighting circuits. At that point the emergency lights could be fed from a separate circuit. I guess the thought process was that there would be no way all 3 normal lighting circuits could go out, if they did that would be a complete power outage and the emergency lights would come on.

There's no such Code requirement for exit signs.

 

[qcroanoke]

Used to be that exit lights (before battery back up) had to be on a circuit supplied from before the service main breaker. The first time I saw that I wondered why there was a separate 20A breaker in an enclosure all by itself tapped off the mains with #12s.

-Hal

I have seen that several times.

 

[Knightryder12]

There's no such Code requirement for exit signs.

Look at 700.12(F)(2)(3).

 

[david luchini]

Look at 700.12(F)(2)(3).

OK. Looked at 700.12(F)(2)(3). There is still no Code requirement for exit signs (with battery) to be on the same branch circuit as the general illumination.

See also Post #4.