Medical MC Cable

Status
Not open for further replies.

dema

Senior Member
Location
Indiana
I have been researching the requirements for hospital grade receptacles and medical MC cable.

Section 517 requires two separate ground paths for all electrical equipment in patient care areas. The definition of a patient care area is largely up to the local jurisdiction. Many hospitals and some inspectors want all equipment within the facility to have the dual grounding paths. The code reads that a conduit path should be one ground path and an insulated copper conductor shall be the other.

It appears that medical MC cable, two grounding conductors, has been approved for use in medical facilities, but I do not see that it meets the letter of the law. Would you please explain to me how it meets the requirements of 517.13.A?

The results of the rest of my research are summarized. Please let me know if and where you disagree. Thanks.

The code also says that receptacles with insulated grounding terminals shall be identified. The use of 'insulated' is unfortunate, since an insulated conductor and an insulted grounding terminal are vastly different things. The insulated grounding terminal in a receptacle is an isolated ground, which is clarified by the fine print note. 517.16 is merely stating that isolated ground receptacle should be so identified. However, some electrical inspectors are taking this to mean that the receptacles should be dual ground ready and that this means hospital grade. Actually, hospital grade has nothing to do with grounding when it comes to receptacles. Hospital grade receptacles have to withstand a number of 'crooked' tests. Plugs have to be jammed into these receptacles at an angle repeatedly without degradation of the receptacles or sparking. That is what constitutes a hospital grade receptacle.

There are various types of metal clad cable:

MC cable, which has a green grounding conductor. Even though it is metal clad, the casing is not rated as a ground path.
AC cable, which has a casing which is rated as a ground path, but has no green grounding conductor. I have been told it is no longer made.
Medical MC, which has an aluminum grounding conductor and a green grounding conductor.
Medical AC cable, which would better meet the letter of the law as it has casing rated as a ground path and a green grounding conductor - but I have been told that it isn't made anymore.

Hospital grade receptacles are only required in patient bed areas - however, some hospitals and electrical inspectors want them everywhere, in all medical facilities.
 
dema said:
I...

It appears that medical MC cable, two grounding conductors, has been approved for use in medical facilities, but I do not see that it meets the letter of the law. Would you please explain to me how it meets the requirements of 517.13.A?

...
517.13(A) "...or sheath assembly..." means the cable's armor plus its respective grounding conductor.
 
AC cable, which has a casing which is rated as a ground path, but has no green grounding conductor. I have been told it is no longer made.


Our local supply house still stocks AC cable. With the price of copper it's cheaper than MC.
 
you can buy MC cable with two green GC, but it does not meet the requirements of 517.13A
AC cable with a green GC does and is commonly used for health care.
However there is a new type of MC cable that is much like AC with the aluminum strip under the cable armor, I keep reading about it, but haven't seen it, yet. Don't know if the new MC cable will meet 517.13.A
 
These inspectors are out to lunch if they think an Isolated Ground Receptacle and a HG Receptacle are anything close to one another simply because they both have identifying marks on them.

In any case, you are correct that per the NEC, HG receptacles are only required at Patient Bed Locations period, however you are right that some facilities use HG receptacles through out, we work at some that do.

This makes it fool proof for the maintenance staff when a receptacle needs to be replaced in a Patient Care Area, they can't grab the wrong item out of their stock.

Isolated Ground Receptacles are not required at all in a Hospital.

The new MC SMART does meet the requirement of 517.13(A), but we regularly buy HFC or HCFC on an almost daily basis, there is no problem getting it and I have yet to actually see a piece of the new MC SMART.

The insulated EGC required in 517.13(B) is not necessary above 7.5' even in a Patient Care Area, see EX #2

Roger
 
ryan_618 said:
The mistake that I see people make is thinking that that exception allows for MC cable, which it doesn't.

Hello Ryan, I agree, that seems to be a common misconception, I have seen the same thinking in this area.

Roger
 
ryan_618 said:
The mistake that I see people make is thinking that that exception allows for MC cable, which it doesn't.

I think that I remember this point from an old thread. Above 7'6" regular old, been around 50+ years AC cable is permitted but not MC. Correct?
 
infinity said:
I think that I remember this point from an old thread. Above 7'6" regular old, been around 50+ years AC cable is permitted but not MC. Correct?
I think I saw some HCF mc cable in a magazine somewhere. Hospital care. It was even green like the ac cable. please advise.
 
Dirk Diggler said:
I think I saw some HCF mc cable in a magazine somewhere. Hospital care. It was even green like the ac cable. please advise.
Mr. Digggler, I have some of the MC SMART cable. The maunfactures rep came out to our office 2 years ago. He left samples for us but the cable was not listed at that time. I have heard that they now have a listing but I have not seen it.
 
Status
Not open for further replies.
Top