[Speedy Petey]

lpf138, Moose made this one and one post almost two YEARS ago. According to his profile his last activity was one minute after making that lone post.
I think it is safe to say he will not be back around to see your reply.

It is always best to check the dates of the posts you are replying to. :thumbsup:


Also, you were misinformed or misunderstand the 9 conductor idea with regard to conduit fill.
The thing is with #14 thru #10 conductors you can have up to nine current carrying conductors before you have to consider derating.
There is absolutely NO "9-conductor" limit.

This is just a very basic explanation. There are many other factors involved with regard to derating and conduit fill in general.

 

[goose134]

to goose134: I could be misinformed, but another thing I've heard around the campfire is about your conduit fill. I hear that no matter WHAT size conduit you use, there's a maximum of only 9 conductors permitted. Meaning you could use a 1" stick of EMT and still only be allowed 9 14 AWG conductors. If so, does that count the neutral's as well? 2 circuits, 2 hot's 1 shared neutral=3 wires? Or only 2?

I realize this is an ancient post, but Petey, you are incorrect. Chicago only allows 9 wires in a pipe. Current carrying or not. This is one of the big differences I spoke of so long ago.

 

[Speedy Petey]

Wow. OK, good to know.
LPF did not mention his location so I just assumed he meant in general.

Thanks for the heads up. :thumbsup:

 

[lpf138]

Sorry.. I found this thread through googling "What are the differences between the NEC and the Chicago code", so I assumed everybody was discussing that! Your right, I should have paid more attention. I understand what the NEC mandates about conduit fill.. And understand derating, and also box fill for that matter, just was curious about something that is now a confirmed difference. Possibly an odd one at that.. Anything else less that hasn't been covered? So far I know of basicallyipe everything you can, if you use greenfield be sure to include a ground, 9 wires maximum, anything else? Anything different from the NEC about smoke alarms?

 

[goose134]

I don't know about smoke alarms. I don't do much residential, but I don't think you need AFCI protection, if that's what you're wondering.

Big differences are service masts must be rigid or IMC

Grounding Electrode conductor sizes also vary. NEC stops at 250 kcmil, I believe. Chicago continues the size calculations all the up. I've pulled a 600kcmil ground for a 4000 amp service before.

In commercial plenum ceilings, fixture whips must be flexible metallic TUBING. Otherwise known as plen-flex. Boxes must be stamped one piece variety with gasketed covers. Conduit fittings must be compression. Low voltage must also be piped. No plenum rated cable run in trays or rings.

These are the ones that leap to mind. I haven't worked outside Chicago in a while so I'd be pressed to remember more.

 

[xxPaulCPxx]

BTW, you don't need to pull the wire into a box to transition from flex to conduit. There are fittings that will allow you to attach flex directly to conduit.

No pipe bending needed either, you can just use flex for your corners instead with those fittings!

 

[Michael Thomas]

What it's worth, at least as regards residential construction in Chicago, conduit bending is becoming an increasingly rare skill, much of the residential new work I see is done with the branch circuits in pre-bent turns with lots and lots of connectors - it's not pretty, and IMO it's not a really good idea because each connection adds a bit of resistance when you pull the wires and has the potential for a sharp edge if the pipe isn't reamed properly after cutting, but it needs code and the Chicago inspectors pass it.

 

[goose134]

I'd be surprised if that were the case in new construction. A 90 is the easiest thing to do. Fittings and pre made bends are more expensive to do. More than likely what you're seeing is DIY with no desire to purchase a bender. Residential bending has never been about pretty, it is all about speed and efficiency. Pre-made 90's offer neither of these things.

 

[frenchelectrican]

Goose .,

Hate to step in your spot but I have a question to ask you real quick due you are famuair with Metro Le Chicago codés speaking of premade 90° bend on half inch EMT are they are at standard bending radius or short bend radius ??

due I have one bender that I can make very short bend { I don't use it often unless it kinda last resort to use it.}

Merci,Marc

 

[goose134]

Marc, the premade bends are almost identical to those you would make with a standard bender. I know of the bender you are referring to, the short radius bender. I've got conflicting information on whether or not the radius provided by the short radius bender is within code. I've never looked at NEC bending radius rules (if there are any). Nor have I measured the radius the bender provided.

That said, I've used them in a pinch and they can be a lifesaver when the time is right.

 

[frenchelectrican]

Goose.,

I am pretty much in the same boat with conflects with bending radius on the conduit on the Americian side however in France side the smallest bending radius we are allowed on 13 mm conduit { the same as half inch conduits } is 80mm { little over 3 inches }and that is pretty tight bend there but normally it will be 160mm radius { about 6 inches }

Merci,Marc

 

[Michael Thomas]

Quick summary of the NEC bending rules:

http://www.anixter.com.my/AXECOM/AXEDocLib.nsf/(UnID)/71C22AE23FF1A43580256F24006EF67A/$file/B-1_7.pdf

 

[134]

Chicago Electric Code

First things first you can't put Romex in BX, maybe you mean Greenfield. Secondly the code doesn't say you can't run more than 3 feet it says no more than 6 feet unless you have a ground wire in which case 14/3 would have to be used. The reason is BX and Greenfield can unspool. ROMEX is not allowed in CHICAGO at all. It gives off a poison gas if burnt, Chicago has the most strenuous code in the world. This is because of the history of fires in our great city. But for your project go ahead and use BX ( I prefer Greenfield ) it's perfectly OK'd by code. You can get a copy of the Chicago Code at the Library just get a Library card.

 

[Speedy Petey]

134, please note that this thread is well over two years old.

Also, you and I both know that fire is NOT the reason Chicago does not allow NM cable. It's FAR more political/union than that.
The "poison gas" thing is simply propaganda scare tactics Chicago uses to perpetuate it's outdated and absurd NM cable codes.

 

[rjniles]

The orginal poster asked this question in 2008 and never returned again to look at the answers.

 

[curiousB]

134, please note that this thread is well over two years old.

Also, you and I both know that fire is NOT the reason Chicago does not allow NM cable. It's FAR more political/union than that.
The "poison gas" thing is simply propaganda scare tactics Chicago uses to perpetuate it's outdated and absurd NM cable codes.

I live in Chicago. It's union/trade driven. It's actually getting worse, not better. Now you need fire sprinkler systems in new residential construction. Oh brother another $$$$$ waster with no valid cost benefit model. Between the two probably $10k in extra housing cost.

 

[Speedy Petey]

I live in Chicago. It's union/trade driven. It's actually getting worse, not better. Now you need fire sprinkler systems in new residential construction. Oh brother another $$$$$ waster with no valid cost benefit model. Between the two probably $10k in extra housing cost.

I think sprinkler systems in homes is an EXCELLENT idea. :thumbsup:
That said, it SHOULD NOT be code required.

 

[d34dfish]

I want to post a link for folks that find this thread in the future like I did, but apparently the system won't allow a link as a first post. This is just a placeholder so I can post the link.