Using FMC (Flex)

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Well just got to vent some. I can see where some people get 'stuck' in a mode of doing things (maintenance) and not use to the real world (construction).

Had a fellow electrician that believed that you could not run FMC (Flexible metal conduit) more than 6ft under any circumstance. Well this was at a 'hospital' , but mind you this is NOT in a patient care area where redundant grounding is required. Just basic locker room for the staff for break (coffee etc) in addition you need a special 'code' (combination lock) to enter this room so no patient can enter even if they wanted to cause its in another wing of the hospital!!. We were low on material and we only had the flex and wire (ground wire as well) to put in the 1/2 inch flex that had to be fished down a wall and then over a tight space with duct work and flex was over 6ft in a celing that would be hidden out of sight.

Well i kindly refered him to the NEC 2005 (the code our state is under) Article 517 and 348 handbook which we had on the jobsite. Even after reading that 348.20 (A)and 517.13 (A), (B) and the (non enforceble)commentary that cleary explained that fmc can be run in unlimited lengths per this article, he still was just bent on the phrase 'well we are not doing that way' since he could not win the arguement over the code. There are no local amendents that prevent this either.

It just bug me sometimes when people get stuck on something (bull headed) on a job that can just be done 'safely' and to code and look professional and still not be done cause 'we just dont do it that way'. Oh well, i get paid the same wheather we do it 'his way' or no way. Ok im done venting.
 
brother said:
Well just got to vent some. I can see where some people get 'stuck' in a mode of doing things (maintenance) and not use to the real world (construction).

Had a fellow electrician that believed that you could not run FMC (Flexible metal conduit) more than 6ft under any circumstance. Well this was at a 'hospital' , but mind you this is NOT in a patient care area where redundant grounding is required. Just basic locker room for the staff for break (coffee etc) in addition you need a special 'code' (combination lock) to enter this room so no patient can enter even if they wanted to cause its in another wing of the hospital!!. We were low on material and we only had the flex and wire (ground wire as well) to put in the 1/2 inch flex that had to be fished down a wall and then over a tight space with duct work and flex was over 6ft in a celing that would be hidden out of sight.

Well i kindly refered him to the NEC 2005 (the code our state is under) Article 517 and 348 handbook which we had on the jobsite. Even after reading that 348.20 (A)and 517.13 (A), (B) and the (non enforceble)commentary that cleary explained that fmc can be run in unlimited lengths per this article, he still was just bent on the phrase 'well we are not doing that way' since he could not win the arguement over the code. There are no local amendents that prevent this either.

It just bug me sometimes when people get stuck on something (bull headed) on a job that can just be done 'safely' and to code and look professional and still not be done cause 'we just dont do it that way'. Oh well, i get paid the same wheather we do it 'his way' or no way. Ok im done venting.

So what way did he want to do it?
 
Had this been a patient care area, 6' would be the maximum length.I did not know this untill after reading 517.13(A).
Rick
 
RUWired said:
Had this been a patient care area, 6' would be the maximum length.I did not know this untill after reading 517.13(A).
Rick


Yes that is true. Its good to know code. Reduntant grounding is to help give the patient an extra layer of protection in case of a potential shock.

However other places in a hospital that are not classified as 'patient care areas' (ie caferterias, maintenance rooms, staff only break/changing rooms) are not subject to this requirement. So 1/2 or larger Flex over 6ft with a ground wire in it can be used.
 
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chevyx92 said:
So what way did he want to do it?

He wanted to use the MC cable listed that had the extra grounding,(where the sheath would provide the extra redundant grounding where you wrap the silver ground wire around the metal cable). He thought that 1/2 flex could not be run over 6ft under any circumstance. This is not true thats why i told him to read the code. Dont get me wrong, I have no problem going above the mininum of code but, the problem is we did not have all the material for the use of that cable in this location at the time. Spending time (wasted) searching for this stuff and having to special order it and 'debating whats code and whats not' when this is a "rush/hurry up and git er done today job" to me is just ridiculous when you have code compliant material and can make it look professionally done.
 
That is MCap......MC all purpose. Thats all they use out here. Wrapping the bond around? This product, simply cut off the #10 al bond strip at the listed connector, no wrap no termination required. Or did you mean AC cable?
 
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dcspector said:
That is MCap......MC all purpose. Thats all they use out here. Wrapping the bond around? This product, simply cut off the #10 al bond strip at the listed connector, no wrap no termination required. Or did you mean AC cable?

Yes i ment AC cable. Over here it is required to 'wrap' that aluminum silver ground around the outer sheath to used in the hospitals here. Hears a discription of what it and link.

http://www.southwire.com/Southwire/StaticFiles/Text/SW_WhitePaper_single.pdf

AC-HCF (Armored Cable ? Hospital Care Facilities):
Designed for dry locations at conductor temperatures not to exceed
90?C. Used in patient care areas of hospitals, medical and other types
of healthcare facilities other than hazardous anesthetizing locations. It is
suitable for all locations where Type AC is permitted. It is constructed of
solid, soft drawn, copper Type THHN conductors and a green insulated
copper grounding conductor. Conductors are individually wrapped
with moisture-resistant, flame-retardant paper covering. Aluminum
interlocking armor is applied over the assembly with aluminum bond
wire inside the armor running longitudinally in intimate contact with the
armor for its entire length.
 
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