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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
grimace OP
624 posts
 
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,
sufentanil's avatar
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sufentanil
782 posts
 
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
gvasale's avatar
gvasale
99 posts
 
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...
jea48
4,459 posts
 
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
gvasale's avatar
gvasale
99 posts
 
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.
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