Use 10/3 romex, not 10/2. The 10/3 feeder has a full size insulated ground and the wires are twisted which goes a long way in rejecting common mode noise while the 10/2 wires are parallel and acts like an RFI antenna. The added cost of the 10/3 will pay back after you’ll most likely find that power cords will have a much less affect over stock cords, as has been my experience.
+1 to the 10/3. And buy it yourself at Home Depot; it's thick enough that the electrician will try to convince you that your overkill is silly, but if you just hand it to him he'll have no choice in the matter. :-)
Be sure to circle back to let us know how it effects your sonics. I don't think you'll be disappointed.
Something that I’ve wondered about, electricians use staples when running cables. Any audible effect ? (as long as they don’t pierce the jacket).I think clips are preferable to staples. That's what my electrician uses.
I ran two independent 20A circuits for my system and one thing to consider is whether to put your circuits on the same phase or opposite phases.
I did the latter and run my monoblocks on one circuit/phase and the rest of my gear (preamp, phono stage, TT, DAC) on the other circuit/phase.
Some folks argue to run the same phase as it minimizes issues with hum, but I believe it’s best to run opposite phases - there shouldn’t be any hum issues if it’s wired properly.
My system is very quiet hooked up and wired this way.
10-2 use silver paste to coat the wire ends before attaching to breaker ,better yet
would be to install breaker panel sub box near where it enters wall and use a grounding rod driven in to the ground 12' 5/8" dia.,then you eliminate ground interference from main supply and of course use a audiophile outlet preferably quadplex and also use silver paste with the connection,helps prevent corrosion in the future ,had very good results with this method.
2 very important considerations for installing 2 dedicated 20 amp duplex AC outlets:
1) Proper wire size for a 20 amp circuit is 12 gauge or possibly as large as 10 gauge...3 conductors. Be careful with anything over 12 gauge.
2) The 2 circuits must be on the same sevice panel buss or you will create a giant antenna and have enormous ground loop hum.
It may be more economical and avoid the creation of the potential antenna effect by just installing a single dedicated 20 amp duplex AC outlet and using a large 20 amp multiple outlet strip. Sometimes simplicity trumps complexity. This technique insures that your dedicated outlet will not have inherent ground loop hum and will supply the power you need.
There are also different grades of breakers depending on the manufacturer of your panel. If you're supplying the parts then do some research on breakers as well. +3 for 10/3 romex.
It will be even less expensive if you "pull" your own wire if you can. No sense in paying a licensed electrician to do grunt work. Just be sure to leave enough length of wire on each end to work with.
There are also different grades of breakers depending on the manufacturer of your panel.Per NEC only the panel manufacture breakers can be used in the panel. Breakers Listed for use in the panel are listed on a label found inside the panel. Usually on one side or the other
+3 for 10/3 romex.What do you do with the bare #10 ground wire in the Romex cable?
10-2 use silver paste to coat the wire ends before attaching to breaker ,better yetOh no, that's a violation of the NEC. All grounds must be bonded together at the service panel; anything less than that is potentially dangerous.
As for the silver paste, I'm not sure that meets code, either. Whether it does or not, I don't think it's a good idea. You want clean, tight electrical connections.
perazzi28 is correct. #12 wire is rated for 20 amps and #10 is rated for 30 amps. If you use a 20 amp breaker it will trip at 85% of rating so what is the point of going to #10. Run a 12/3 romex that is a neutral with two lines and a ground. This will give you two dedicated 20 amp cicuits with one run. Same labor cost. By the way lots of us in the electrical fields are also audiophiles.
Here's a thought - if you have the space, consider a sub-panel adjacent to your rack depending on where the equipment is located from an aesthetic stand-point.
I added a dedicated 60amp sub-panel using 6-gauge in its own conduit from the main panel. That opens up the option of 240 volt power conditioners at the rack which is nice and very short runs from the panel to the outlets.
I grounded the sub-panel separate from the main panel using a grounding plate buried outside connected with 6-gauge grounding wire. Good fun.
#12 wire is rated for 20 amps and #10 is rated for 30 amps. If you use a 20 amp breaker it will trip at 85% of rating so what is the point of going to #10.Derating the wire will reduce voltage drop. The calculation of the proper gauge wire for a given amperage hinges on the distance of the wire, so you can't quite say, " #12 wire is rated for 20 amps," although it is generally true.
I grounded the sub-panel separate from the main panel using a grounding plate buried outside connected with 6-gauge grounding wireThat's a violation of the NEC and potentially hazardous. All grounds must be bonded together at the service panel, without exception.
The highest quality ground is a low impedance ground, and that's the ground provided by your utility. If there's an issue with your utility's ground, it's their responsibility to correct it.
10-3 was used for greater distance. My nextdoor neighbor who is a electrician ran that. So I have 2 20amp. At the wall we put 2 sets of outlets each set is on a separate breaker
Outlet. Outlet. Outlet Outlet
Outlet. Outley. Outlet Outlet
1. 2. 1. 2
Breaker Breaker Breaker Breaker
It is this way so I can decide how much load is on each beaker.
Yes, it is either
12-2 Romex or 10-2 Romex...."cleeds" is on it!
You can debate which one to run for a 20 amp duplex outlet but what you have is a Black Positive conductor, a White Neutral conductor, and a Green Ground conductor.
In the Service Panel: the 20 amp breaker will have only the Black wire,
The White will be attached to the Neutral Bar and the Ground to the
If I may, the power company does not supply a ground wire.
You only have three supply wires coming in from your utility/power company.
2 are the supply wires...Positives...one for each half of a 200 amp service or whatever your home has. The third wire is the Neutral wire.
No ground comes to your home. Your ground is made-up via a 6' copper grounding rod driven in the ground.
cerberus79 14 posts 05-06-201710:40am
Early in this thread is was recommended that 10-3 with ground be used instead of 10-2 with ground for a single 120V 20 amp dedicated branch circuit. The idea is to use one of the insulated conductors for the equipment grounding conductor instead of bare equipment grounding conductor.
(I assume the red would be rapped with green marking tape to identify it as the equipment grounding conductor.)
I assumed the above wiring method is what falconquest was referring to in his post, that I responded to.
So my question,
What do you do with the bare #10 ground wire in the Romex cable?
I misspoke (wrote)? 10-3 would be three conductor with ground. 10-2 is sufficient. Please check this out from Vince Galbo @ MSB.....
Run a 12/3 romex that is a neutral with two lines and a ground. This will give you two dedicated 20 amp cicuits with one run.No, that would be 2 separate 120V circuits. A 3 wire 120/240V multiwire branch circuit. Two separate 120V circuits with a shared/common neutral conductor.
A 120V dedicated branch circuit is a branch circuit with a dedicated,
Equipment grounding conductor.
A true dedicated circuit does not share a raceway, conduct, or cable assembly, with any other circuits.
Multiwire branch circuits are not recommended for feeding audio equipment. Especially where audio equipment is connected together by signal wire interconnects.
It also should be mentioned the 2 circuits of the 120/240V 3 wire multiwire branch circuit must be connected to a 2 pole breaker, per NEC.
Only the imbalanced load, of a 3 wire multiwire branch circuit will return on the shared neutral conductor back to the source, the electrical panel. The balanced load of the 3 wire circuit is in series with the two hot ungrounded conductors.
Example: If the connected load on L1 to neutral is 5 amps and the connected load on L2 to neutral is 5 amps, zero amps will return on the neutral conductor of the branch circuit back to the source. The two loads are in series with one another, essentially being fed by 240V.
So say Digital equipment is fed from one of the separate 120V circuit outlets and the analog is fed from the other separate 120V circuit outlet, Only the imbalanced load of the digital equipment and analog equipment will return on the neutral conductor. The balanced 120V loads, of the two connected loads, will be in series with one another. Do you really want the digital hash going back out on the power cord/s of the digital equipment coupled to the power transformer/s of the analog equipment?
Here is a very good video on how a multiwire branch circuit works.
Jea48, The NEC does not clearly define that and it is left as a design perrogative. It is understood that a dedicated circuit is one where only one appliance will use that circuit. A neutral can be shared but only one appliance per breaker. Some elect to run a neutral for each as a design choice. In either case the neutral is run back to the panel and attached to the neutral bar where all the other neutrals are.
cerberus79 17 posts 05-06-2017 9:09pm
Multiwire branch circuitshttp://ecmweb.com/code-basics/branch-circuits-part-1
"single-pole circuit breakers with handle ties identified for the purpose"
The tie used must be a Listed tie for the intended purpose.
Or, just use a 2 pole breaker......
Or, in the case of a 3ph. 4wire multiwire branch circuit a 3 pole breaker.
Just going from memory I believe this was added to the 2008 NEC. After State and local AHJs adopted the new language, at least in my state, the 120V as well as 277V multiwire branch circuit became a thing of the past. I don’t know of anyone that installs them today, or for the last 8 years.
Please read the first 36 pages of this white paper.
quote from page 31
The “Conduit Transformer”•
This finally explains what drives 99% of all ground loops!
•Load current in line and neutral produces opposing magnetic fields since instantaneous current flow is in opposite directions
•Imperfect cancellation magnetically induces voltage over the length of the nearby safety ground conductor
•Strongly affected by geometry and proximity of wires
•Highest voltages with randomly positioned wires in conduit
•Lower voltages with uniform geometry of Romex®
•Voltage is directly proportional to load current, wire length, and rate of change in current or ∆I/∆t
•Mechanism favors high-frequency harmonics of 60 Hz
•For constant current in L and N, induced voltage rises at 6 dB/octave
... the power company does not supply a ground wire.
No, you're mistaken: You're confusing ground with safety ground. They are two different, though related things. All grounds and the neutral must be tied to together at the service panel. Whether you are subject to NEC or not, failing to comply with this practice is dangerous.
The ground rod - codes usually requires two of them today - is predominately for lightning protection, and is not a reliable (low impedance) path to ground.
There is no magic associated with grounding rods, although many audiophiles imbue their ground systems with exceptional importance. The whitepaper linked by jea48 is an excellent treatise on how grounds work (and don't work):
Consider that electrical systems in airplanes, cars and on boats work quite well without what you mistakenly define as a ground system.