Dedicated line

Dave:

If you want to do it right, here is the way it ought to be. First, isolated ground receptacles are a benefit only from reducing EMI and RMI and is well worth the extra copper, IMO. Second, if you are using a subpanel for your two dedicated outlets, it is important that all grounding conductors (the white neutral and the green isolated ground) run all the way back to the main service grounding point (ground rod, utility neutral and/or water pipe). You cannot bond these wires to the subpanel because the electrical load will be split in parallel with the main panel. In plain English, it will energize the subpanel and create a danger of electrical shock to all appliances plugged into circuits between the main panel and the subpanel.

When you install the subpanel, make sure to tell the electrician it is a subpanel. The electrician will then place an isolator (a piece of rubber or plastic) under the subpanel's neutral and ground bar, electrically isolating it from the house grounding system. Then, the electrician must run a separate and dedicated neutral wire from the subpanel's isolated neutral bus to the main panel's neutral bus. Also, a separate ground wire from the subpanel's isolated ground bus to the main panel's neutral bus is required since you are running isolated ground. Most panels do not come with a separate ground bus (grounds and neutrals are one in the same), but you can buy them separately. Now, when you wire your two dedicated receptacles to the subpanel, the neutral and the grounds are uninterrupted to the main service grounding point, even though they terminate at the subpanel. This way, a future electrician need not worry about adding additional circuits to the subpanel.

The point is to have the grounding point be the earth and the receptacles, with no bonds in between.

The subpanel should be rated for at least 60-amps and should be fed from a two-pole 60-amp breaker from the main panel. Use copper wire, never aluminum. I would run the wires from the main panel to the subpanel in EMT and I would twist the wires to cancel common mode noise. The neutral from the subpanel can be run in the same tubing but the ground should be in a separate conduit. If your codes allow, the subpanel should be lugged, instead of having a main circuit breaker. The breaker from the main panel is adequate to protect the feeder.

Let me be a bit clearer, I was thinking of having an isolated ground for the two dedicated circuits in the sub-panel, not the receptacles. Does this make more sense and is it worth doing? I don't think I have any grounding issues right now and I have no idea how clean or dirty my power maybe.

thanks.

In the VTL owners manual they write, " To achieve the best performance, we recommend that a dedicated 30A line be installed for each amplifier, with a minimum of 20A required for each amplifier". My understanding 30A breaker, 10ga wire 20A outlet. This is what I did. Do not believe it is for sound but to be able to meet the demand of the siegfried amps. Either way the best and most correct way. At least that is my understanding.

In further support of the comments by Gs5556 and Jea48 about having a separate grounding rod for the dedicated lines, see section 1.2 of this document.

Regards,
-- Al

Grounding is my biggest concern, my electrician said I can drive a 6 foot grounding rod into the ground and attach the 2 dedicated lines to it. Does this make sense?
Davea33

Find another electrician! A licensed electrician.....

As for the branch circuit wire.
If you go with #12 wire use a 20 amp breaker.
If you go with #10 wire you still must use a 20 amp breaker per code.

If you use a 20 amp receptacle by code it cannot be connected to a 15 amp branch circuit breaker. A 20 amp rated receptacle can only be connected to a 20 amp branch circuit, by code....
#12 awg copper wire is rated for 20 amps.

this all sounds like over kill to me ...12awg or 10awg in real world applications would have no sound difference at all.

The mention in my post was unclear. I put in a new service panel for the entire house and drove two ten foot grounding rods which has helped my electrical issues. I think the prior posts agree with the ten gauge. The draw in my system was due to two Classe CA-150's being driven hard on a circuit which had other items such as lights and the front end. The reason for the ten gauge is also for future or current audio components that like power. My amps can demand up to 650 watts each which is a lot for a typical house circuit. I live in an area that is wet and prone to dirty electric. Hope this helps. Steve

You cannot ground your receptacles to a separate ground rod. In fact, no grounded conductors can be connected to a grounding connection on the load side of the main service disconnect. That means that the neutral wires of your dedicated circuits cannot be bonded to the subpanel's neutral bar unless that neutral bar is electrically isolated from the subpanel with a separate grounding conductor from the neutral bar to the main panel.

The reason you cannot run separate ground rods for branch circuits (or have more than one grounding point of your electrical service) is that a lightning strike will cause a voltage potential between the ground rods, resulting in damage to whatever is plugged into the receptacle. That's why Telco and CATV services are grounded at the same point as the electric service.

12 ga is rated for a 20amp circuit, so you can use it with a 20 amp breaker.
10ga is better though IMHO!

10ga cryoed Romex from Vh Audio is hard to beat.
I would recommend solid core, as I have tried stranded before and there is no comparision, solid core wins hands down for dedicated lines!
I think 8ft grounding rod is code, but most electricians use 6ft because it is less work and gives up nothing compared to 8ft.
6ft is all you need.

Salevick, what additional info do you need?

My electrician says if I use 10 gauge wire then I will need a 20 amp circuit. Since the run is so short and the draw is minimal I thought 15 amp 12 gauge wire would be fine with a 15 amp circuit. Can you hook up 10 gauge wire to a Teslaplex? Any reommendations on wire?

Also, plan on using one of Alan Maher's circuit breaker filters. Since I'm rewiring, I plan on putting it in the inside of the wall. Any thoughts on this.

Thanks for everyones response.

If you live in a dry climate two eight foot grounding rods spaced 6 feet apart is recommended.

I like the idea of 10 gauge wire on 20 amp circuits. Your electrician will know the code for your area and the best way to run the ground.

I'll second the use of 10awg as it sounds better than the 12awg I have for my sources. The third line I plan to install will be 10awg!

Steve, can you tell us/me a little bit about how you did the grounding? Is there a particular site for info on this?
Thank you in advance.

The question you ask needs more information. The issue of dedicated lines is a very good solution for many problems. The gauge of the wire should be commensurate to the draw. I would strongly recommend ten gauge or larger on twenty amp circuits. The grounding is important and I drove two ten foot grounding rods. This combination improved my electrical draw since I on loud passages would dim the lights with my mono blocks. The incoming power from the utility is very dirty therefore I assembled a power conditioner from Transcendent Audio for the front end. The amps are plugged into the wall in the 20 amp service with a hospital grade or better outlet Hope this helps. Steve