main power distribution earth and proprietary grounding

[delfin]

hi,

i am from macedonia. at the moment i am visiting some friend who can help me with a design of electricity distribution for my future studio. i have to admit that i read through posts here, and what i firstly understood is that i have to connect my proprietary digged ground rode to the electrical leg of audio equipment. therefore, that MY ground is NOT to be interconnected with incoming main distribution ground. in another words, all my studio logic outlets will connect to the neutral from incoming power, to the phase (phase1) from incoming power AND to the my ground (and not to the incoming ground)...

ok fine, but then i read further and one poster mentioned that proprietary ground HAS to be connected to the incoming main distribution ground and bridged with neutral (also from incoming main distribution)...
thats where i lost it altogether...

what is already done:
a) a rode diged inside the soil (far right in my picture)
b) incoming main distribution three phase tick cable (top left) is in the place
c) main fuse break cabinet (black and grey grid) is placed on the wall
d) copper cable from the rode is brought to the main fuse break cabinet
e) all studio logic power outlets (audio processors, console, screens, computers, speakers, etc...) are marked and designated to phase 1


my questions are:
1)
what i have to do next... connect all studio logic outlets to the phase and neutral from incoming power distribution and to the incoming main power ground AND my proprietary ground OR only to my proprietary ground?

2)
do i need to have separate fuse break cabinet for HVAC and lighting and apartment?

THX,

pic attached,

cheers and many thx,

d.

[BriHar]

1. If the outlets are individually wired, each to it's own breaker, then the green wire in your cable should suffice, as the grounds runs are also individually run back to a common bus. However if multiple outlets will be connected in parallel (which is the typical case) then the green wire should be used only for grounding the duplex box if these are metal, otherwise it can be clipped and insulated at the box, and a separate ground wire should be run from each outlet back to a common point - usually the ground bus in the breaker panel. The common point can however be a separate (local) grounding bus panel, but should nonetheless be connected to the main panel ground as well as your rod.

2. A separate breaker panel should not be necessary but it is good if the outlets in your studio can be on their own phase.
HVAC and basically anything with motors or dimmers should definitely be on a separate circuit and even better on a separate phase.

[Speedskater]

STOP!!! The Ground Rod or the other types of connections to Mother Earth are for safety! All the ground wires (PE,EGC) must be connected at the point where electrical power enters the building (Service Entrance), all the wires to Mother Earth must be connected at this same point. In a correctly wired building, the connect to Mother Earth will have very little impact on the audio quality. (It only impacts audio quality if there are already wiring errors.)

Please read the papers below before starting your project.
(Yes it's over 150 pages, but well worth reading)

The Jim Brown of Audio Systems Group white paper:
"Power and Grounding for Audio and Audio/Video Systems"
http://www.audiosystemsgroup.com/SurgeXPowerGround.pdf

The Bill Whitlock of Jensen Transformers Seminar paper:
http://www.jensen-transformers.com/an/g ... eminar.pdf

"Power White Paper" from Middle Atlantic.com:
http://www.middleatlantic.com/power.htm

or a different version of the same paper

"The TRUTH" from ExactPower of Middle Atlantic Products:
http://www.exactpower.com/elite/wpapers.aspx

[delfin]

hi BriHar!

1. If the outlets are individually wired, each to it's own breaker, then the green wire in your cable should suffice, as the grounds runs are also individually run back to a common bus. However if multiple outlets will be connected in parallel (which is the typical case) then the green wire should be used only for grounding the duplex box if these are metal, otherwise it can be clipped and insulated at the box, and a separate ground wire should be run from each outlet back to a common point - usually the ground bus in the breaker panel. The common point can however be a separate (local) grounding bus panel, but should nonetheless be connected to the main panel ground as well as your rod.

i am going to have outlets in a group of 4 (just like those extension cables, just in an outlet form).
one cable (3x2.5mm²) is handling that group of 4 outlets. so 1 green ground wire goes from them to the breaker panel. is that OK? or u are trying to say that beside that (3x2.5mm²) cable i need to bring 4 more individual wires for grounding all 4 outlets within a group?

2. A separate breaker panel should not be necessary but it is good if the outlets in your studio can be on their own phase.
HVAC and basically anything with motors or dimmers should definitely be on a separate circuit and even better on a separate phase.

they will be on a separate phase definitely, but within same breaker panel...


can u suggest what would be the best scenario according to my picture? what to connect with what, so i can come to my electrician with some suggestions as he is not in studio business... do i have to connect digged rode ground (dark green) with incoming main ground and all greens from individual lines to them? in one word, all three green kinds together at the breaker panel?


many many thx,

d.

[delfin]

STOP!!! The Ground Rod or the other types of connections to Mother Earth are for safety! All the ground wires (PE,EGC) must be connected at the point where electrical power enters the building (Service Entrance), all the wires to Mother Earth must be connected at this same point. In a correctly wired building, the connect to Mother Earth will have very little impact on the audio quality. (It only impacts audio quality if there are already wiring errors.)

Please read the papers below before starting your project.
(Yes it's over 150 pages, but well worth reading)

The Jim Brown of Audio Systems Group white paper:
"Power and Grounding for Audio and Audio/Video Systems"
http://www.audiosystemsgroup.com/SurgeXPowerGround.pdf

The Bill Whitlock of Jensen Transformers Seminar paper:
http://www.jensen-transformers.com/an/g ... eminar.pdf

"Power White Paper" from Middle Atlantic.com:
http://www.middleatlantic.com/power.htm

or a different version of the same paper

"The TRUTH" from ExactPower of Middle Atlantic Products:
http://www.exactpower.com/elite/wpapers.aspx

wow, Speedskater,

thx so much for the links.
i have to admit i get lost after 10 or so pages.
i will try to work on this... but i am not sure if i really need myself to understand it all as i am more of an artist.
however, i will certanly read through it and try to catch as much as possible.

i will kindly ask u if u can comment on what i wrote up there to previous poster about where and how to connect "three different kinds of greens". i know that nobody like to recommend something like that, but i am assuring u i am not going to blindly follow anything myself without electrician. i just like to hear opinion based on a drawing up there.

thx so much...

d.

[BriHar]

Yes in this case each receptacle will require a separate ground wire in addition to the 3 conductor cable. These separate ground wires must be wired directly from the ground pin of the receptacle to the ground bus of the panel - each individually. Do not wire them from receptacle to receptacle as you will the power cable!

do i have to connect digged rode ground (dark green) with incoming main ground and all greens from individual lines to them? in one word, all three green kinds together at the breaker panel?

You got it - 4 kinds actually. (What speedskater said regarding bonding the service ground to the rod at the service entrance is correct.)

the ground from the service, from the rod, the greens of the 3 conductor cables (one per circuit) plus the individual groundwires from each receptacle.

so 1 green ground wire goes from them to the breaker panel ... beside that (3x2.5mm²) cable i need to bring 4 more individual wires for grounding all 4 outlets within a group?

Yes

[delfin]

Yes in this case each receptacle will require a separate ground wire in addition to the 3 conductor cable. These separate ground wires must be wired directly from the ground pin of the receptacle to the ground bus of the panel - each individually. Do not wire them from receptacle to receptacle as you will the power cable!

do i have to connect digged rode ground (dark green) with incoming main ground and all greens from individual lines to them? in one word, all three green kinds together at the breaker panel?

You got it - 4 kinds actually. (What speedskater said regarding bonding the service ground to the rod at the service entrance is correct.)

the ground from the service, from the rod, the greens of the 3 conductor cables (one per circuit) plus the individual groundwires from each receptacle.

so 1 green ground wire goes from them to the breaker panel ... beside that (3x2.5mm²) cable i need to bring 4 more individual wires for grounding all 4 outlets within a group?

Yes

wow,

i am soo confused now, but also i want to understand it correctly:

so, my outlets have 4 receptacles (for powering 4 devices) in a group.
1.power cable AND neutral will go from receptacle to receptacle.

2.proprietary ground cable will not go from one receptacle to receptacle but each will have its own cable from receptacle to the common ground buss at the fuse cabinet?

3. what do i do with ground green cable that comes to the outlet with phase and neutral???

i am really confused why it is not correct to use just that within 3 wire cable without propietary extra wires for the ground... please bear in mind that i really want to understand and i believe u, ofcourse...




can i have more than 1 outlet with 4 receptacles (in my case they are in a group of 4) on a same fuse/breaker?

THX!

d.

[delfin]

ok,

to make it clearer, as my english is not the best, i made a quick ugly drawing...

thats how my outlet with 4 receptacles is configured.
live, neutral (left, right) and ground touch (up and down) in each receptacle.
dark greens - proprietary extra ground lines
light green - "internal" 3 wire cable ground

which version is correct, a) or b)?
i guess u will say a), but then i do not understand what is a benefit of having individual lines... please help...
what is then situation when u use in studio extension outlet cable??? surely, ther eis just one ground bridged there?

and dont laugh for a drawing

[BriHar]

Now your drawing is throwing me a curve.
In your original graphic you showed four separate duplex outlets. I assumed these (group of four to the circuit) would be distributed around the room. Your new drawing shows all four 'sockets' side by side, as if in a single panel. If the latter depiction is correct then you should be allright with plan (a) ground from 3-Wire conductor connected because the distance between plugs is negligible hence the Potential Difference between outlets is a nonissue.
If the individual sockets are distributed around the room however, then (b) would be the way to go.

I know it seems almost counterproductive and nearly downright stupid to wire in this fashion, but the concept is "Star Grounding" which you can look up on the internet, and the idea is to help prevent ground loops caused by potential differences between different grounding points in the studio. I mentioned previously that this grounding scheme can be terminated in a separate local 'grounding panel' which I personally find preferable, particularly if the mains panel is far away. This local bus is connected to your system ground, i.e. breaker panel ground, but the important point here is that all the grounds in the room are referenced to the same physical point - minimizing the issue of potential difference.

The green wire in the 3-wire cable is for safety and should be used exclusively for grounding conduit, the housing or installation box in the suggested star-grounding concept. If the said housings are plastic, then this wire can be clipped and insulated at the termination point but should be connected nonetheless at the main panel.

If you can have a look at the book Home Recording Studio Build it Like the Pros by Rod Gervais often mentioned here, there is a diagram showing this wiring concept (at least in the second edition).

P.S. If you have AV equipment (e.g. satellite receiver, or cable box etc) or a stereo receiver in your studio, be careful as these usually have their own ground reference point and will very likely have a potential difference which will most assuredly introduce problems if plugged into your studio circuit and will require isolation. But that is another theme.

[Speedskater]

I have a question:
How does the power wiring get from the breaker box to the wall outlet?
In the US some homes and many commercial building have metal tubes (conduit) with individual Hot, Neutral and Ground wires inside.
But most homes have a 3 conductor plastic cable.

[Speedskater]

Next question:
Is the fuse (circuit-breaker) box, the building main box, or will your studio have it's own sub-box?

[delfin]

BriHar,

i think we will finally understand each other, or should i say, now it makes all more sense to me, and maybe i was not totally precise about all... will answer bit later as i am too busy right now...

Speedskater,

will answer a bit later...

thank you guys for great help!

[delfin]

hi,

ok, here is a (somewhat simplified but better than previous) drawing of my situation.

when i talked about group of 4, i talked about 4 receptacles in a row (sorry about my english, that's also an issue here )...
the first time i talked about this i sent a drawing with ready-made outlets from Google sketch-up library and there was only with 2 of them

now, this shows an rough position of my control room, studio and very small machine room where also fuse panel is located.
all cables are 3x2.5mm² cables with hot, neutral and ground enclosed in some kind of semi-thick plastic/gum.
as i on the top i will have apartment, i have 2 separate fuse panels.
it is like this:

main power 3phase income is located in machine room 5x5mm²

one cable 3x3mm² feeds from there and departs upstairs to apartment where all the fuses of apartment are located, for this phase nr. 3 i used

fuse panel in machine room handles all fuses from studio and control room
all audio gear + logic (computers, monitor screens, etc...) is on phase nr. 1
all lighting and aircones and ventilation and few outlets used for vacuum cleaner, etc are on the phase nr.2

question 1: do i need to have all 4 receptacles within 1 outlet group on a same fuse? (all mine are in group of four, this time exaclty as on the picture)

question 2: is this what i have on my picture star grounding, EVEN WITHOUT EXTRA WIRE FROM EACH RECEPTACLE as BriHar suggested? when first reading his kind answer i couldn't understand why on the earth i would need another cable just for ground if (as he later pointed out from my pic) distance is so small.

can i leave it like this???



question 3: so i do not need extra wire for ground? (just to make it definitely sure to myself)


question 4: what do i do with my digged ground rod? today i talked with one audio consultant and he pointed that area where i am is pretty dry and rocky, stoned... so, he says that my ground is never going to be as it should be, in other words he is sure that btw main power distribution ground and this my ground is going to be a potential difference that will not be acceptable... he says, that as i have, new modern installation, he will go only with main power grounding for a start, while having my ground just in a stand by to experiment if needed.
he also strongly suggests to purchase online UPS device of 2 kW for audio phase 1.


question 5: any problems with having a wireless router and switch in a very close proximity of a console desk and rack outboard?


guys, many thx..... i am an artist and just a bit technical person...
thx a million for the help!!!!

[Speedskater]

For US readers "3x2.5mm² cables" are about 13AWG wire.
And "one cable 3x3mm²" is just smaller than 12AWG.

Let me get back to this tomorrow, if the grandson doesn't interrupt all day.

[BriHar]

I don't have time at the moment to answer proüerly but I'll get back real soon.

BTW In the meantime you should really follow the instructions in http://www.johnlsayers.com/phpBB2/viewtopic.php?t=3231