# Emergency Branch Circuit



## IvanE (May 5, 2013)

so here is a very interesting thing I have heard many times before about the EM Branch Circuits: today I was working on light fixtures in the Comed room and my coworker tells me the same thing again about EM Lighting Circuits and EM Exit Circuits, Chicago Codes Requirement Size Number 10 wire only... I ask him if they are 20 amps circuit and he says that yes they are 20 amps. I said that we should be allowed to pull number 12 wire for these types of EM branch Circuits, but we ended up using number 10 wire for the EM Lighting Circuit.
Anyone here knows where in the Chicago Code book it says that this is a Requirement for Emergency branch circuits?


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## seabee41 (Dec 21, 2010)

Check article 700 in Chicago code book


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## seabee41 (Dec 21, 2010)

Unless your co worker can give you a code ref I don't not see it in article 700


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## Shockdoc (Mar 4, 2010)

And I do the opposite of that here, I generally run all #12 wire circuits for lighting and receptacles. I run a #14 circuit for Em and Ex lights.


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## wildleg (Apr 12, 2009)

I couldn't find it, but that doesn't mean it's not true. Read the Chicago code (title 18) here for yourself: http://www.amlegal.com/nxt/gateway.dll/Illinois/chicago_il/title18buildinginfrastructure/chapter18-27chicagoelectricalcode*?f=templates$fn=altmain-nf.htm$3.0#JD_18-27-90.5


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## 360max (Jun 10, 2011)

wildleg said:


> I couldn't find it, but that doesn't mean it's not true. Read the Chicago code (title 18) here for yourself: http://www.amlegal.com/nxt/gateway.dll/Illinois/chicago_il/title18buildinginfrastructure/chapter18-27chicagoelectricalcode*?f=templates$fn=altmain-nf.htm$3.0#JD_18-27-90.5


link no good


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## IvanE (May 5, 2013)

I have read the code book meany times before but I don't remember reading this about EM branch circuits, I think running #10 is over kill. But if you need to prevent voltage drop from exiting 3% on long runs, then # 10 wire and option depending on voltage drop calculations.


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## Glen springfield (Dec 14, 2013)

I have found the same thing here in Missouri on my prints. It is not a code issue but just the way the eng. wants it so we pull #10 wire around the circuit and drop a #14 wire to the fixtures.


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## IvanE (May 5, 2013)

yes but that doesn't mean that is code I will like to know what do they base this practice?
My coworkers still do the same mistake over and over again on using #10 in fixtures but the quick connects don't take #10.


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## Meadow (Jan 14, 2011)

Arent emergency light and exit signs supposed to be independent of each other when the backup source is a legally required back generator? Ive never found the code to that but always done it.


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## Awg-Dawg (Jan 23, 2007)

meadow said:


> Arent emergency light and exit signs supposed to be independent of each other when the backup source is a legally required back generator? Ive never found the code to that but always done it.


 
This is the article for hospitals that shows the separation of circuits.

517.30(C)(1)

The exits and emergency lights are on the Life Safety Branch (517.32) and can share the same raceway.


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