# HCF cable..............



## Chris Kennedy (Nov 19, 2007)

220/221 said:


> tons of EMT with ground wires landing in every box and device and, you want *another* ground wire.
> 
> 
> Makes.no.sense.


Your kind of missing the point. What I have quoted above is 517 compliant. The EMT complies with 517.13(A) (250.118) and the wire EGC complies with 517.13(B), thats golden.


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## ampman (Apr 2, 2009)

isolated ground, not sure what you are talking about


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## JmanAllen (Aug 3, 2011)

If your using metal conduit you don't need a redundant ground it's if your using mc they want the green mc cause they don't consider the sheathing to carry the ground

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## BBQ (Nov 16, 2010)

JmanAllen said:


> If your using metal conduit you don't need a redundant ground it's if your using mc they want the green mc cause they don't consider the sheathing to carry the ground


This is incorrect.

Chris has it right.


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## Jlarson (Jun 28, 2009)

220/221 said:


> just started a little job converting some office space into "doctors" offices.


They're letting you do hack up exam rooms now 

I want an address so I can avoid this doctor's office :laughing:


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## 220/221 (Sep 25, 2007)

Chris Kennedy said:


> Your kind of missing the point. *What I have quoted above is 517 compliant*. The EMT complies with 517.13(A) (250.118) and the wire EGC complies with 517.13(B), thats golden.


I am definately missing the point. Make it simple for me 

And.....I don't see anything above???

So EMT with a ground (required here anyway) is compliant but MC has to have two grounds?

What about flex? PVC??? I remember reading it years ago and I couldn't use underground PVC to an island recep. Hed to be IMC. :jester:



> I want an address so I can avoid this doctor's office


Don't you have a well that need romex run to it? Get back to work.


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## Fibes (Feb 18, 2010)

220/221 said:


> I am definately missing the point. Make it simple for me


Go to 250.118, item 1 and any of the other items 2 through 14 must be used together in a 517.13 installation


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## Pete m. (Nov 19, 2011)

220/221 said:


> So EMT with a ground (required here anyway) is compliant but MC has to have two grounds?.


The HCF MC cable is essentially no different (grounding wise) than EMT with a separate EGC.



220/221 said:


> What about flex? PVC??? I remember reading it years ago and I couldn't use underground PVC to an island recep. Hed to be IMC. :jester:


*517.13 Grounding of Receptacles and Fixed Electrical*​

*Equipment in Patient Care Areas. *
Wiring in patient care
areas shall comply with 517.13(A) and (B).​​*(A) Wiring Methods. *​*
*​*
*All branch circuits serving patient
care areas shall be provided with an effective ground-fault
current path by installation in a metal raceway system, or a
cable having a metallic armor or sheath assembly. The
metal raceway system, or metallic cable armor, or sheath
assembly shall itself qualify as an equipment grounding​conductor in accordance with 250.118.

PVC.... no
Flex.... yes, but very limited. see 250.118(5)

Pete
​


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## erics37 (May 7, 2009)

220/221 said:


> I am definately missing the point. Make it simple for me


Simple: whatever wiring method you use in a patient care area needs to qualify as an equipment grounding conductor itself. All metal conduit counts. Normal MC cable does not count, because the sheath is not considered to be a qualified EGC. Therefore, you use hospital grade MC cable because it has that little bonding wire in it that touches all the links of the sheath and thus bonds them all.

So overall, the normal way to wire patient care area crap is, run metallic conduit and pull an EGC wire in it, or run hospital grade MC cable. You can do it other ways too, but the bottom line is that whatever wiring method you use needs to qualify as an EGC.

Now if you also have isolated ground stuff in a patient care area, then you'll have THREE grounding conductors :thumbup:


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## JmanAllen (Aug 3, 2011)

erics37 said:


> Simple: whatever wiring method you use in a patient care area needs to qualify as an equipment grounding conductor itself. All metal conduit counts. Normal MC cable does not count, because the sheath is not considered to be a qualified EGC. Therefore, you use hospital grade MC cable because it has that little bonding wire in it that touches all the links of the sheath and thus bonds them all.
> 
> So overall, the normal way to wire patient care area crap is, run metallic conduit and pull an EGC wire in it, or run hospital grade MC cable. You can do it other ways too, but the bottom line is that whatever wiring method you use needs to qualify as an EGC.


Ok didn't I say basically the same thing but. BBQ said I was wrong

I think where the confusion came in is that in Oklahoma we have to always pull ground wires no matter the conduit so I was saying in emt you don't need a 2nd ground wire Going off what I'm used to with always having one in the conduit 

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## Peerless Design (Dec 3, 2011)

We've all seen plenty of instances where conduits pull apart from each other or apart from the box connectors, thus interrupting the path to ground. There is a lot of metallic equipment used in healthcare that can become energized in the event of a ground fault. This is even a bigger concern on critical branch circuits in wet locations that do not need to be protected by GFCI by code. The nature of the business can leave patients extremely vulnerable to electric shock. This is the reason for a redundant ground path.

HCF cable is not allowed by some jurisdictions. The reasoning I've been given is that MC cable uses a reduced ground size in the amor that is not rated for the same level of current as the circuit conductors. It is not seen as meeting the redundant ground path requirement.

Jim Smith, PE, LC, RCDD, CET


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## BBQ (Nov 16, 2010)

JmanAllen said:


> Ok didn't I say basically the same thing but. BBQ said I was wrong


Maybe I misunderstood you?



JmanAllen said:


> If your using metal conduit you don't need a redundant ground


That is the part that sounds wrong, we do need a redundant ground.


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## Southeast Power (Jan 18, 2009)

I seem to remember a job where we installed green MC and then had to cut the bare wire off at each end. 
The inspector had an issue with it but I think the instructions it came with it said to cut it. We gave him the instructions and he left. Nothing more was mentioned about it.


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## joethemechanic (Sep 21, 2011)

Peerless Design said:


> We've all seen plenty of instances where conduits pull apart from each other or apart from the box connectors, thus interrupting the path to ground.


Or worse yet MC pulled apart and becoming a high resistance path to ground.


Look into the MGM hotel fire. It was a piece of yanked apart MC/BX/Greenfield/whatever. And it came into contact with some part of the building's steel structure. I can't remember why it had current on the ground conductor though.

Failure chain thing I guess


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## MarkyMark (Jan 31, 2009)

jrannis said:


> I seem to remember a job where we installed green MC and then had to cut the bare wire off at each end.
> The inspector had an issue with it but I think the instructions it came with it said to cut it. We gave him the instructions and he left. Nothing more was mentioned about it.


That's the Southwire MC-AP-HC cable. Quickest and easiest cable there is to use for patient care areas. I think it took inspectors everywhere for a loop the first time they saw it.


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## JmanAllen (Aug 3, 2011)

BBQ said:


> Maybe I misunderstood you?
> 
> That is the part that sounds wrong, we do need a redundant ground.


Ya I forgot that other states don't make you have a ground wire in every pipe that's what I was referring to. That you don't need 2 ground wires in metal conduit just one and the pipe

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## 220/221 (Sep 25, 2007)

> whatever wiring method you use in a patient care area needs to qualify as an equipment grounding conductor itself.


My question is....why?



> We've all seen plenty of instances where conduits pull apart from each other or apart from the box connectors, thus interrupting the path to ground


This makes a good case for a ground wire in EMT (which is required everywhere in AZ) but says nothing about the *extra* ground in the HCF mc. It already has a ground in it. What's the point of the second one?




> The HCF MC cable is essentially no different (grounding wise) than EMT with a separate EGC


The ground in the EMT works if the EMT comes apart. That makes sense. Two grounds in themc makes no sense.




> The nature of the business can leave patients extremely vulnerable to electric shock. This is the reason for a redundant ground path.


At least they are already at the hospital.:laughing:

Sorry NEC but, it's stupid. Put a ground in the EMT, it's a good idea anywhere. Two gounds in a single cable is pointless. Outlawing PVC is also stupid.

This is one of those NEC things that they didn't think through, They wanted a ground wire in EMT installations but didn't write the code to specifically address it.


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## BBQ (Nov 16, 2010)

Yeah, ah what is really stupid is going off about something you don't have any knowledge about.:laughing:


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## RePhase277 (Feb 5, 2008)

I think the reasoning behind it is that the small amount of current that would just startle most of us could actually kill someone in a compromised state, like under anesthesia. So, if you have a system where the ground has become open, then you introduce the potential to kill someone by a dose of current that wouldn't normally be deadly.

So if you have EMT with a ground, and the pipe becomes separated, no problem, the green wire will still be there. Or the other way around, if the wire somehow gets loose, then the EMT will still be intact. And if they both are loose, then the circuit has probably stopped working anyway.


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## BBQ (Nov 16, 2010)

InPhase277 said:


> I think the reasoning behind it is that the small amount of current that would just startle most of us could actually kill someone in a compromised state, like under anesthesia.


That is pretty much what I have always heard, that and the fact you may be opened up so skin resistance is gone.


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## chicken steve (Mar 22, 2011)

> Two gounds in a single cable is pointless


well here's where the terminology gets in the way

because they're NOT the same animal....

~CS~


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## Julius793 (Nov 29, 2011)

Did you connect the 2 wires to different grounding screws? Cuz I'm thinking isolated ground like already said


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## BBQ (Nov 16, 2010)

Julius793 said:


> Did you connect the 2 wires to different grounding screws? Cuz I'm thinking isolated ground like already said


Welcome to the forum Julius, no this thread is not about IGs, it is about meeting the redundant grounding requirements required for receptacles and fixed electrical in patient care areas.



> *517.13 Grounding of Receptacles and Fixed Electrical
> Equipment in Patient Care Areas.* Wiring in patient care
> areas shall comply with 517.13(A) and (B).
> 
> ...


If you happened to have an IG receptacle in those areas you would have 3 grounds, the raceway, and two insulated grounds.


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