ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
Air Compressor feeder conductor sizing
by Potseal. 01/15/18 09:08 PM
VDE 0100 to introduce AFCIs
by LongRunner. 01/15/18 11:38 AM
Under carpet cable?
by HotLine1. 01/15/18 09:57 AM
Any New Years Resolutions?
by Bill Addiss. 01/13/18 10:21 AM
diazed fuses
by RODALCO. 01/13/18 07:58 AM
New in the Gallery:
Housebilding DIY wiring
SE cable question
Who's Online Now
0 registered members (), 5 guests, and 11 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
isolated ground receptacles #164461
06/03/07 11:05 PM
06/03/07 11:05 PM
watersparkfalls  Offline OP
Member
Joined: Mar 2005
Posts: 222
Washington...Not DC
is mc cable ok to use for an isolated ground
circuit? or should i pipe it and pull individual conductors.
keeping in mind that this is going to be for a recording studio and noise elimination is very important....
thanks
H2o

2017 / 2014 NEC & Related Books and Study Guides
Re: isolated ground receptacles [Re: watersparkfalls] #164462
06/04/07 12:49 AM
06/04/07 12:49 AM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,165
Estero,Fl,usa
It is OK if you get "medical" MC with 2 EGCs or the new LiteMC with the bond conductor and an additional green wire for the IG.


Greg Fretwell
Re: isolated ground receptacles [Re: gfretwell] #164463
06/04/07 01:14 AM
06/04/07 01:14 AM
watersparkfalls  Offline OP
Member
Joined: Mar 2005
Posts: 222
Washington...Not DC
after futher reviewing iso ground online...
i've read that installation in plastic boxes nailed to wood frames wouldn't require a forth conductor and that the bare conductor in nm 12-2(home run) ie..dedicated would suffice the iso requirement for device....yet i cant help but wonder if noise couldn't somehow get through nm and cause havoc on my installation. where 12-3 would seem better because wires are twisted and red wire identified green would be insulated and perhaps ensure a better noise free installation? any thoughts? would be cost effective in nm with plastic boxes...but if metal sheilds isolated circuit then perhaps 12-3 mc into metal box would be best route.
thanks,
H2o

Re: isolated ground receptacles [Re: watersparkfalls] #164471
06/04/07 10:16 AM
06/04/07 10:16 AM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,165
Estero,Fl,usa
I bet most of the "noise" is going to actually happern in the studio itself from bad leads and ground loops in that equipment. If the whole system is fed from a single dedicated circuit I am not sure where the noise would come from. Where I can see a problem is where you have interconnected equipment on two different circuits fed from different phases. I have had that in my home MP3 system. I assume I am seeing the added voltage drop across the neutrals or something. Swapping the phase on one end so both ends were on the same phase seemed to fix it.


Greg Fretwell
Re: isolated ground receptacles [Re: gfretwell] #164593
06/06/07 07:48 PM
06/06/07 07:48 PM
R
resqcapt19  Offline
Member
Joined: Nov 2000
Posts: 2,148
IL
There is no evidence that isolated grounds serve any real purpose. The evidence says one of 3 things will happen in about equal proportions...it makes the problem worse, it makes it better, or it makes no change.
Don


Don(resqcapt19)

Featured:

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
MarkC10
MarkC10
CA, Inland Empire
Posts: 43
Joined: September 2013
Show All Member Profiles 
Top Posters(30 Days)
sparky 24
Admin 19
Potseal 13
Popular Topics(Views)
243,508 Are you busy
180,293 Re: Forum
170,798 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.013s Queries: 15 (0.003s) Memory: 0.9677 MB (Peak: 1.1091 MB) Zlib enabled. Server Time: 2018-01-16 09:51:50 UTC