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emergency exit and emergency back up lights

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ksavoie

Electrical
Mar 6, 2006
24
I have an emergency exit and emergency back up lights that all have battery back up power. My boss is telling me that the circuit that feeds the back up lights and exit sign must be on its own circuit in its own conduit. I’m telling him that the battery is the “emergency circuit” and other source can be from a “normal supply”. I want to tie the emergency exit and emergency back up lights on the source side of existing lights in the vicinity. Which way should I go? Please Help!
 
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Why are you not satisfied with the responses in thread238-217080? It would be far better to continue that thread than to start another thread on the same topic.
 
Maybe you should post in the professional ethics forum or overcoming obstacles, since this seems to be more suited to that.
 
Sorry for the re-post! I am just frustrated! I keep tell my boss what was said in the forum and the way I interpret the NEC Code art. 700, and he keeps telling me that we are all wrong. I also think it smarter to tie into the lights in the vicinity so if a breaker trips at night and the batteries run down, then the next day when the hall light don’t come on, someone will notice.
 
Maybe our boss is right. Code aside my experience with battery back up fixtures is that they are a pain in the long run. The long run in this case may be 2 or 3 years.
After the batteries go you have failed test, battery replacement, finding batteries that may or not be made any more, finding ballast that may or not be made any more etc. It may be the easy and cheap way out of a design but is it ethical to pass on the headache to the owner? It may save the owner some time and money in the future by using a dedicated conduit system today.
It's an easy way out of a design job to use battery powered fixtures but it's a "Wal-Mart" job.
 
BJC, The client and my boss want to use fixtures with battery back up in them. With that being said, my boss is telling me that the supply circuit feeding these battery back up fixtures is an “emergency circuit” and must come from a dedicated circuit along with being installed in it own conduit. I’m telling him that the battery is the “emergency circuit” and the supply circuit doesn’t have to be a dedicated circuit.
 
I just called the city inspector and he told me as other told me, as others told me, in this forum that the emergency lights with battery back up power must be feed from the same circut as the lights in the vicinty. My boss is going to have a cow!
 
ksavoie,

Ask the boss how the battery-powered emergency lights are supposed to come on and do their job if the branch circuit feeding normal lights in the room trips?

Have him read NEC 2008, 700.12(F). The only exception is if an open area is supplied by three or more normal branch circuits for lighting. Otherwise, connection to a circuit separate from the normal lighting branch circuit is not permitted.

Let us know how you do!

Good on ya,

Goober Dave
 
ksavoie,

Here's a quote from 700.12(F): "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.

Have fun!

Goober Dave
 
Sorry I'm just a designer and he still doesn't get it. So now I explained it to a Chemical Engineer and he understands so he is going to explain it to my boss EE. Man it is hard to try to do the right thing.
 
Its possible that your boss does get it, he just doesn't follow the code. Sometimes its more important to meet the intent rather than the letter. Although in this situation I'm not sure how that is possible.

I assume your boss has been doing this for a while, and obviously has had no problems with his plans getting approval from the local AHJ. If your boss is the one sealing the drawings, and the AHJ is approving plans, and you've got it on record that you disagree with the way in which the lights are circuited, let him stamp away.
 
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