Star Grounding System Question

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Hi Def
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Star Grounding System Question

Post by Hi Def »

Hey everyone. This is really cool that this section was added to the forums! Lots of great information. I am in the process of wiring all of my rooms (electrical) right now and have a question regarding the Star Grounding System.

I've searched through and through everywhere I thought possible on the internet and have found nothing. There are many sites where people say they've used it for there electrical system but none of them say how to actually impliment it! Does anyone know of a site where this information can be gathered? Is it imperative that I use this system in my studio? My goal is to have no grounding or ground loop problems from circuit to circuit. Is it possible?

Thanks everyone.

M
giles117
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Post by giles117 »

http://www.saecollege.de/reference_mate ... stics4.htm

Details the star grounding system.

Image

I have an old joke. The Better the Ground, the better the sound.
Bryan Giles

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Just living life and having fun with all this talent YHWH Elohim has given me.
Hi Def
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Post by Hi Def »

Thank you Brian. A couple of other questions if I may...

1) By reading that section at the SAE site, am I correct in saying that when using your typical 14-2 or 12-2 standard wire for outlets, I should disregard the provided ground wire and run a seperate, bare copper wire for my grounds?

2) When using this method, does each circuit get its own grounding path back to the service panel?

3) Does each circuit ground at its own rod in the ground?

My electrical system for my building is just a 100amp service off of my house service. It terminates at the studio building with two grounding rods just outside the building.

Thanks for all of your help.

M
Hi Def
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Post by Hi Def »

Sorry for the wrong spelling BrYan! :oops:

M
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Post by Aaronw »

Hello Hi Def,
1) By reading that section at the SAE site, am I correct in saying that when using your typical 14-2 or 12-2 standard wire for outlets, I should disregard the provided ground wire and run a seperate, bare copper wire for my grounds?
I guess my first question to would be: Are you running Romex w/ 14/2 or 12/2? Or will you be running conduit?

If you're running Romex, and depending if your having this inspected by your local codes, you may want to run a home run to each outlet.

If your running conduits, and using metal enclosures, it will be simpler. You can tie (or daisy chain) the Hot and Neutral together for several outlets, but you want to run a separate ground wire for each outlet. eg: a quad outlet box, you would have 2 ground wires (one for each isolated ground outlet), and you'll also need one (as I found out later) for the box enclosure itself.

In other words, for each outlet you have, you want a home run ground wire that runs back to the panel where they all join together, and then to your rod.


2) When using this method, does each circuit get its own grounding path back to the service panel?
Answered above.
3) Does each circuit ground at its own rod in the ground?
You just have the one rod normally. In reading other posts, I've seen some people use a couple rods and tie them together, so there's always a good ground.

:D

Aaron
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Post by knightfly »

Here's a link to a 6 page thread on RO where we thrashed this to death some time back - rather than regurgitate all of it, you can find pretty much everything you need here, including relevant code sections to show your inspectors, electricians, etc -

http://www.recording.org/posts16729-0.h ... highlight=

Grab a cup of coffee and some snacks, this will take a while... Steve
giles117
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Post by giles117 »

yeah, what they said. LOL
Bryan Giles

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Just living life and having fun with all this talent YHWH Elohim has given me.
Hi Def
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Post by Hi Def »

Hey thanks everyone! That article on recording.org was great....but.... :? Still a little confused.

The way my current power is run to the building is as follows. From the main house panel I'm running 100amp service to the studio building via a 3 wire #4 cable. No ground. Just two hot and a Nuetral. OK...It's hooked up to a 100amp panel in the studio. I've installed a grounding bar in the panel and took a #6 cable from there out of the building to two grounding rods 8 feet apart. All is good right? :)

There was talk in this article that if in my situation, as described above, that the ground and nuetral must be bonded! This totally confuses me and is contradicted further in the article as nuetral holds power and would introduce a ground loop. I believe Rod G. advised not to run the IGs back to the same panel for fear of introducing interference, but to install a seperate box with a grounding rod that is bonded to the studio main panel. Hope this isn't confusing the way I've worded this.

Bryan: In the diagram you provided from SAE, where is the center point of the star? By this I mean are all of the circuit's outlet grounds tied together somewhere outside the panel and then that one wire carries to the ground inside the panel?

Thanks everyone for your help. Hopefully this isn't becoming a pain in the ....

M
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Post by giles117 »

Ah the flexibility, you can have all the grounds meet inside the panel, wrap them in electrical tape so that they do not touch the panel in any way and run a nice copper wire strand outside to your grounding rod.

Dont waste your time getting confused.

Do not tie the Ground and the nuetral together.

Never a pain. I have installed a number of these type of grounding systems even before I read this article. All my years doing live sound and dealing with .04v AC on the ground side of things and having to figure out methods to quiet that mess down. :)

I tend to carry ground rods with my PA deals and my live recordings. you never know when you gotta break it out and hammer it in. ;)
Bryan Giles

FOH Live, Live Remote & Studio Engineer
Producer

Just living life and having fun with all this talent YHWH Elohim has given me.
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Post by Guest »

Thanks Bryan. You've been a tremendous help! One more question and then I think I got it. Ok actually two! :wink:

1) In your experience with installing these grounding systems, did you put the IGs in their own conduit or did you just run it along witht he romex?

2) When you say tape all of the grounds and avoid touching the panel with them, There's where you lost me. All of my other grounds from lights and other outlets are coming back to that same grounding bar in the panel...correct? :? Or are you saying bring IG wires in the box, bypassing the panels ground bar entirely, and run it directly to the grounding rod outside?

Your help is very very appreciated man! Thanks a ton.

M
giles117
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Post by giles117 »

In a commercial install they usually run individual wires for hot, neutral and ground through conduit. That is how they can run all the grounds to a separate box with ease. It is a single wire all alone.
However when using romex the 3 wires are running together. You can, when the wire approaches the box split it and run the hot and neutral into your service panel and the ground to the separate grounding box.
However you attempt it make sure that your grounds for the studio are seperated from the grounds from the rest of the facility. If you can install a separate breaker panel just for the studio that is even better then it would not matter if all the grounds came to your grounding strip that you ground to an outside grounding rod.
Bryan Giles

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Just living life and having fun with all this talent YHWH Elohim has given me.
Hi Def
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Post by Hi Def »

Hey Bryan, thanks for the quick reply! Yes I am running a seperate box for the studio. It's a whole seperate building with 100amp service from the house.

So...I can tie these IGs directly into the panels grounding bar? I don't need a seperate ground box as suggested on the recording.org article? Sorry to ask again but, is it ok to run this 12Gage grounding wire along with the romex, not in conduit?

I've started wiring already and have run the 12-2 romex (not using the provided ground) and then running another single 12gage wire for the isolated ground. They are run next to each other and not in conduit. Is this kosher?

I'm concerned about grounding in the same panel because the rest of the buildings power needs come off of this same panel. Like the AC, lighting and other stuff you have in a studio. Maybe it's nothing to be concerned about. Thanks for your help Bryan.

M
giles117
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Post by giles117 »

Yep you'll be fine.

Just keep all the studio electrics on one leg of power and the ligting on the other leg of power. with most boxes every other breaker position is the same leg.

IE brkers 1,3,5,7,9 = same leg
2,4,6,8 = same leg
so 1 would be a differnt leg than 2. :)

And the grounds from the studio electrics keep those isolated from the other grounds like I indicated above.

I have never had any issues doing this. Been wiring small studios since 1994. No hums no buzzes since. :) Including doing Audio for video Studios.
Bryan Giles

FOH Live, Live Remote & Studio Engineer
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Just living life and having fun with all this talent YHWH Elohim has given me.
Hi Def
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Post by Hi Def »

Bryan..........You Kick Ass! Thanks a million!

I've been starting to wire all the stuff and everything you say makes perfect sense, and I'm understanding exactly what to do except one thing! :?

When you say isolate all grounds on the studio electrics from the rest of the stuff, do mean at the panel as well? Because ultimately, all the studios grounds from all of the lighting etc. will come back to the ground bar in the panel. Therefore, it's not technically isolating the ground is it? Should I install a separate grounding bar and stake specifically for my studio electrics?

Sorry man to keep this going but after this one issue is resolved I'll be straight with the whole iso ground think I think! :lol:

Please let me invite you (if your ever in Central WI) for a beer or two or ten! :) Your help has been awesome! Thanks.

M
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Post by giles117 »

Hi Def wrote: Should I install a separate grounding bar and stake specifically for my studio electrics?
Exactly. However keep this in mind when you screw that ground bar to your panel... It will be in electircal contact with the other grounding bar.

Best bet will be to do as Rod G says which is to run those (studio electrics) ground wires to a separate box (they usually are pretty cheap 30 bucks or so) and ground them all there and connect that to the outdoor earth grounding rod.
Bryan Giles

FOH Live, Live Remote & Studio Engineer
Producer

Just living life and having fun with all this talent YHWH Elohim has given me.
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