Wiring main panel box for dedicated 20amp line.


I'm getting ready to install a dedicated 20 amp line and came across something I wasn't expecting. I have a single GE main panel box that's about ten years old. When I opened the box I was expecting to see neutral wires at one bus bar and the ground wires attached to the other, with the black wire - of course - attached to the circuit breaker.

Instead, I found the neutral and ground wires for each outgoing wire attached to the same bus bar on adjacent screws. I've since read that this is common practice and apparently up to code on a main panel.

To install a new 20 amp line, I could duplicate this setup with adjacent vacant spots on one of the bus bars and a new breaker, but I'm wondering if using a common bus bar for both the neutral and ground wires is suitable for a hi-fi application? The whole idea is, of course, to have a dedicated, properly grounded circuit for my gear. Also, if it's not ideal, would a small sub-panel be a desirable solution?

I'd be grateful for anyone's expertise. Thanks!
grimace
A sub panel would be wired via a 4 conductor wire (10-3 w/ground for 30a or 6-3 w/ground for 50a.) BUT the neutral and ground of this wire would go to the same neutral/ground bus bar in your main panel box so I don't see any gain or difference unless you need more circuits w/a sub panel box. So, IMO, if you need only one circuit, just hook up to the main panel box as you described.

IMHO, I would also run a second dedicated line for digital components only, and it needs to be on the same side of the breaker box as the other dedicated line. This will help with isolation to the analog components.
The electric panel is an extension of the great parallel connected network. You really don't want all of the breakers on say the left, & nothing on the right. Each side is fed from one of the pair of live wires in the feed. You're better off, if you really need another 20 amp circuit to do it on the opposite side.
What you have now is correct,you will have a dedicated 20 amp circuit! I don't see what a sub- panel would accomplish. A ground and a neutral are a horse of another color! At the main coming into your panel they are still tied in together.
Your right Yogiboy that the mains come in as a single line, but for some reason you can get more noise from one side of the panel verses the other. For this unexplained noise issue, a sub panel might be quieter I guess it would depend on where the sub panel was pulled from, certainly either the dedicated line or the sub panel should be pulled from the opposite side of the panel as motors are on. On my panel I moved all the motors, refrigerator, boiler, dishwasher, washing machine and well pump) to one side of the panel. My dedicated circuits come from the other side. I don't have a sub-panel, but if I did, I would pull it from the quite side and consider using fuses vs switch breakers.
The reason why noise does not filter equally across the panel in that it's all connected is beyond my knowledge. I do know in my house things got quieter when I switched all the noise to one side.
Jadem6,You are lucky that that works for you. The only problem with that is that having all high current stuff on one side can trip the main breaker. The main panel is 240 volts,120 on each side! Like I said it's great that it works for you!
You're better off, if you really need another 20 amp circuit to do it on the opposite side.
The breaker box should balanced on both sides, however dedicated lines for audio need to be on the same side. Searching the forums about this, dedicated lines on opposite sides is said to cause phase problems and increase the chance for ground loop hum.
T1s49: Vistualy every electronic device uses a power supply where you know, AC is converted to DC...

There hasn't been any issues with phasing of DC that I've ever heard of. Maybe I just don't have the experience...

Maybe I just need to hook up the old Techtronics scope and watch the sine wave for a few hours, sort of like watching the test pattern fot TV in days gone by...
Thanks for the responses. I only needed one outlet and I placed the ground and neutral wire in adjacent spaces on the right bus bar. I chose that one only because it's the one the main ground wire attaches too. Seems to be working fine. The far bigger issue was wishing the wire through the wall, but even that wasn't too bad.

Regards,
For the main panel, the ground and neutral tie into the same bar, so what you did is correct. For a sub panel, they go to different bus bars.

Michael
T1s49: Vistualy every electronic device uses a power supply where you know, AC is converted to DC...

There hasn't been any issues with phasing of DC that I've ever heard of. Maybe I just don't have the experience...
12-23-13: Gvasale
Gvasale,

I believe T1s49 is referring to the Hot Lines, legs, of the electrical panel. He used the term phasing in his post a common mistake when referring to the Hot legs of a single phase electrical panel where the service conductors are fed from a single phase transformer with a split phase secondary winding.

At any rate, it is an established practice that when using more than one branch circuit to feed audio equipment, that is connected together by ICs, all branch circuits should be fed from the same Line, leg, from the electrical panel.
All from L1 or all from L2 but not from both.


12-23-13: Tls49

You're better off, if you really need another 20 amp circuit to do it on the opposite side.
The breaker box should balanced on both sides, however dedicated lines for audio need to be on the same side. Searching the forums about this, dedicated lines on opposite sides is said to cause phase problems and increase the chance for ground loop hum.

The Truth

Jim
So, you have a hypotheticaly 220v amplifier, If you say the transformer (pole) has a split phase secondary, then the amp should have ground loop & other indescribable issues?

I go back to the ground is the same ground, no matter what & the phase is normal (single), Not split, or would ac motors not run, right? Motors, capacitor start, "split' phases themselves, right?

Going back to the power supply, all are rectifying AC to DC and usually have full wave rectifcation and hopefully adequate filtering, of one or two stages & regulation too.

I can't download your link yet, but I'll keep trying.

This, and I don't mean to offend anyone, is really kind of out there if you know what I mean.
So, you have a hypotheticaly 220v amplifier, If you say the transformer (pole) has a split phase secondary, then the amp should have ground loop & other indescribable issues?
12-24-13: Gvasale
I see you do not live in the USA or Canada. Here in the US the power that feeds most houses is fed from a single phase transformer with a split phase secondary winding.
You will just have to trust me on that. Or you could do a little research on the subject and learn for yourself.
Here is an Example to get you started.

You spoke of 220V. I assume you live in a country that uses 220V power to feed residential dwelling units, houses.
Just guessing, because I have no idea, just 220V is fed to the premises. One Line, leg, of the 220V feed is intentionally connected to earth making it the Grounded Conductor, neutral. The other Line, leg, is the Hot the ungrounded conductor.

If that is the case you do not have the same power situation as we do here in the US.

I go back to the ground is the same ground, no matter what & the phase is normal (single), Not split, or would ac motors not run, right? Motors, capacitor start, "split' phases themselves, right?
I haven't the foggiest idea what you are saying.

Going back to the power supply, all are rectifying AC to DC and usually have full wave rectifcation and hopefully adequate filtering, of one or two stages & regulation too.
Really.....
And how about coupling capacitance leakage from the primary winding of the power transformer of the equipment. Add that to audio equipment that uses an equipment grounding conductor.
Having 120V branch circuits fed from both L1 and L2 feeding equipment that is connected together by ICs only adds together leakage voltage because of the 240V potential of the L1 and L2 fed circuits.

And then in the case of audio equipment that uses a safety equipment. Poorly designed equipment is susceptible to ground loops when the signal ground of the equipment is also connected to the chassis. In this case one piece of equipment may be fed from L1 and another from L2. A 240V potential is present on the 2 hots feeding the audio equipment. Here also any leakage to the equipment ground will be additive and possibly cause a ground loop hum.

I can't download your link yet, but I'll keep trying.
Keep trying.....

This, and I don't mean to offend anyone, is really kind of out there if you know what I mean.
12-24-13: Gvasale
I suggest you do a little research on the subject before you start bad mouthing others. You just might learn something in the process.
Jea48: Like I said, not trying to offend anyone, but I've never experienced any problems with ground loops. Also, this seems to have a lot of opinions running in both directions. I did get to thet website by just going the the short ***.com and viewed what was availabele. Just like those who swear by and others who swear at power conditioners.

I also did a web search on ground loops and again never had "sound bars" on video or any other symptoms of the problems. I guess I'm just lucky... But we so have three wire 220/240 distribution 110 ground 110 feed. Just over time the voltage has gone up to 120 ground 120. And measuring shows it can run a little higher.

Are you upset because I don't have their problems? Is it like when you own a Mercedes everything about it comes with Mercedes prices? Sorry, really.

It's almost like the greater the progress in this hobby the greater the problems.
Are you upset because I don't have their problems? Is it like when you own a Mercedes everything about it comes with Mercedes prices? Sorry, really.

It's almost like the greater the progress in this hobby the greater the problems.
12-25-13: Gvasale
LOL, I suggest you reread the thread, especially your posts, then answer your own question.