517.13
- Thread starter MEP
- Start date
- Status
- Location
- New Jersey
- Occupation
- Journeyman Electrician (retired)
Re: 517.13
Super neutral is type MC cable and is not a substitute for HCFC which provide redundant equipment grounding conductors.
Super neutral is type MC cable and is not a substitute for HCFC which provide redundant equipment grounding conductors.
Re: 517.13
I agree with Infinity, Super Neutral MC will not provide the redundant grounding provided by HCFC.
There is a hospital grade MC on the market now, but it will have a runner inside the sheath the same as HCFC does.
As an aside, there may be another problem if any of these home runs are from the Critical or Life Safety Branches, flexible cables are only permitted in specific cases, and overall circuitry is not one of them.
See note # 3 below, and notice overall branch circuit wiring is not included.
I agree with Infinity, Super Neutral MC will not provide the redundant grounding provided by HCFC.
There is a hospital grade MC on the market now, but it will have a runner inside the sheath the same as HCFC does.
As an aside, there may be another problem if any of these home runs are from the Critical or Life Safety Branches, flexible cables are only permitted in specific cases, and overall circuitry is not one of them.
See note # 3 below, and notice overall branch circuit wiring is not included.
Roger
Re: 517.13
The Super Neutral Cable is used for home runs (normal power only) on Patient floors, doe this affect your response at all?
The Contractor has also suggested installing a ground buss at every Normal Panel connecting all of the MC jackets directly to the ground buss in the panel. And at the junction box at the end of each homerun the metal jacket be connected with a through bolt to the redundant ground within the box insuring that there is redundant grounding( the 2 green wires) and conductivity of the metal jacket just in case for some unlikely reason that the armor should be separated. Does this offer an acceptable solution per the electrical code and Hospital regulations?
{Moderator's Note: Edited to remove a request for assistance outside the scope of the Forum.}
[ November 01, 2005, 12:01 PM: Message edited by: charlie b ]
The Super Neutral Cable is used for home runs (normal power only) on Patient floors, doe this affect your response at all?
The Contractor has also suggested installing a ground buss at every Normal Panel connecting all of the MC jackets directly to the ground buss in the panel. And at the junction box at the end of each homerun the metal jacket be connected with a through bolt to the redundant ground within the box insuring that there is redundant grounding( the 2 green wires) and conductivity of the metal jacket just in case for some unlikely reason that the armor should be separated. Does this offer an acceptable solution per the electrical code and Hospital regulations?
{Moderator's Note: Edited to remove a request for assistance outside the scope of the Forum.}
[ November 01, 2005, 12:01 PM: Message edited by: charlie b ]
Re: 517.13
Installing a "ground bus" in the panel will not make the sheath of standard or Super Neutral MC an Equipment Grounding Conductor as recognized in 250.118.
Read the links below.
http://www.healthcareengineering.net/archive/receptacle/Article_from_RTT99_Launch.pdf specifically Reference Grounding Point
and
http://www.afcweb.com/prod-cat.htm
notice in this link the "Reference and Ratings" of each type of cable, you will see that compliance with 517 is not included in the MC information.
Roger
[ November 01, 2005, 10:27 AM: Message edited by: roger ]
Installing a "ground bus" in the panel will not make the sheath of standard or Super Neutral MC an Equipment Grounding Conductor as recognized in 250.118.
Read the links below.
http://www.healthcareengineering.net/archive/receptacle/Article_from_RTT99_Launch.pdf specifically Reference Grounding Point
and
http://www.afcweb.com/prod-cat.htm
notice in this link the "Reference and Ratings" of each type of cable, you will see that compliance with 517 is not included in the MC information.
Roger
[ November 01, 2005, 10:27 AM: Message edited by: roger ]
Re: 517.13
I agree with Roger. I notice you mentioned "2 green wires". I've heard that this was once proposed to the NEC, and rejected by the NEC, as an alternate method of ensuring a ground connection.
The ground aside, I can't believe the contractor used flexible MC cable for the homeruns. I would have guessed there would have been project specifications that prevented this. I wouldn't ever allow a contractor to use MC or AC cable for home runs in a hospital. I would always specify wire in metal conduit.
One other note, MC cable must be supported and secured every 6'. Did the contractor do that?
Steve
I agree with Roger. I notice you mentioned "2 green wires". I've heard that this was once proposed to the NEC, and rejected by the NEC, as an alternate method of ensuring a ground connection.
The ground aside, I can't believe the contractor used flexible MC cable for the homeruns. I would have guessed there would have been project specifications that prevented this. I wouldn't ever allow a contractor to use MC or AC cable for home runs in a hospital. I would always specify wire in metal conduit.
One other note, MC cable must be supported and secured every 6'. Did the contractor do that?
Steve
- Status