The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Sprinklered equipment 26-008
by bigpapa
12/02/16 04:24 PM
On Delay Relay with Auto Reset
by Potseal
12/01/16 09:59 AM
Wow, that was close!
by jraef
11/28/16 07:06 PM
Earthquake in New Zeeland
by RODALCO
11/27/16 11:25 PM
Calling all Non-US members!! (Non-US only)
by Tjia1981
11/27/16 06:33 AM
New in the Gallery:
12.5A through 0.75mm˛ flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 13
HotLine1 9
Texas_Ranger 8
sparkyinak 7
Trumpy 6
Who's Online
1 registered (gfretwell), 129 Guests and 6 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#92072 - 02/25/05 02:07 AM Physical Protection
shortcircuit Offline
Member

Registered: 06/27/04
Posts: 608
Loc: massachusetts
When isolated (not continuous between enclosures) sections of metal conduit are used for physical protection of nonmetalic cable,like for a floor penetration for exsample, is it required to be grounded?

Code refrences please.

shortcircuit

Top
2014 / 2011 NEC & Related Books and Study Guides
#92073 - 02/25/05 05:52 AM Re: Physical Protection
George Little Offline
Member

Registered: 01/18/04
Posts: 1492
Loc: Michigan USA
Maybe 250.86 Exception No 2 covers the question.
_________________________
George Little

Top
#92074 - 02/25/05 06:38 AM Re: Physical Protection
shortcircuit Offline
Member

Registered: 06/27/04
Posts: 608
Loc: massachusetts
Thanx George Little...and what determines the distance of "short sections"...

For example could I penetrate a plastered wall with romex, enter 30 feet of EMT with bushings on each end and exit the other end and go back into a wall on the other side of the garage without grounding the EMT at all? The EMT would be provideing physical protection of the romex.

shortcircuit

Top
#92075 - 02/25/05 11:02 AM Re: Physical Protection
gfretwell Online   content

Member

Registered: 07/20/04
Posts: 9045
Loc: Estero,Fl,usa
From a practical sense, the most likely places where a cable could energize the sleeve are the ends, so the length won't change that risk much. If you are talking about the raceway being energized by an unrelated circuit we fall back to the arguments about bonding that steel beam.
(and we don't want to kick that tar baby again)
_________________________
Greg Fretwell

Top
#92076 - 02/25/05 01:21 PM Re: Physical Protection
shortcircuit Offline
Member

Registered: 06/27/04
Posts: 608
Loc: massachusetts
gfretwell...I was not thinking so much about the may become energized from the outside, but was thinking what would happen if this EMT providing physical protection were to become damaged itself from a inadvertent impact of some sort and then becoming energized by the circuit it protects.
Guess that I'm reaching again

shortcircuit

Top
#92077 - 02/25/05 01:47 PM Re: Physical Protection
gfretwell Online   content

Member

Registered: 07/20/04
Posts: 9045
Loc: Estero,Fl,usa
I guess the real question is how you would bond the raceway to the RX without a box to open up the jacket in.
_________________________
Greg Fretwell

Top
#92078 - 02/25/05 04:51 PM Re: Physical Protection
earlydean Offline
Member

Registered: 12/22/03
Posts: 749
Loc: Griswold, CT, USA
The same way we have to bond that steel 90 in the UG service PVC run that isn't 18 inches below grade. With a ground clamp or bushing and a wire to the ground bus in the panel.
_________________________
Earl

Top



ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals