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isolated ground receptacles #164461 06/03/07 11:05 PM
Joined: Mar 2005
Posts: 236
watersparkfalls Offline OP
Member
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

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Re: isolated ground receptacles [Re: watersparkfalls] #164462 06/04/07 12:49 AM
Joined: Jul 2004
Posts: 9,571
G
gfretwell Offline
Member
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
Joined: Mar 2005
Posts: 236
watersparkfalls Offline OP
Member
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
Joined: Jul 2004
Posts: 9,571
G
gfretwell Offline
Member
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
Joined: Nov 2000
Posts: 2,148
R
resqcapt19 Offline
Member
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)

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