Power amp loading on house wire

[chris ma]

Do you see any problem? with this set up to the electricity panel in the house? All amps are individually/sequentially power up or down so the switch on surge should be kept low.

Regards,
Chris

[chris ma]

Now I think if I want to power them on with just one switch I can put a soft start circuit inside the fuse box and use the breaker switch as all my amps turn on switch.

[x. onasis]

Is your "fuse box" a service panel containing fuses or breakers?

A 15 amp circuit requires only 14 ga. wire and a 20 amp 12 ga.

Why do you feel the need for 10 ga.?

Going to the service panel to switch your sound system seems a bother. If your concern is for a dedicated circuit and a single switch that's not on the amps, why not a switched outlet?

If separate circuits are wanted, you could go a step further and save some power by load balancing, by using one 115V leg for each circuit, 12/3 + ground to a double pole switch and split and switch a duplex receptacle in a two-ganged box.

[Peter Daniel]

If you use 10ga wire, you need appropriate fuse in the box, on that line. You should also need a proper receptacle in the wall, but I leave this up to you. I had good results with those orange, hospital grade receptacles, available frome HD.

I'm also running 10ga lines and I observed improvement in the sound, comparing to 14ga lines, better dynamics and punchier bass. I'm using 2 different phases for left and right channels and, IIRC, 30 A fuse.

If you check Stereophile's Room Tunes, I believe one of the articles describes installation of dedicated power lines http://www.stereophile.com/finetunes/

[x. onasis]

Peter's right that if you run 10ga. wire into your service panel, everything downline on that circuit MUST be rated 30A, but the breaker doesn't need to be.

After looking again at your needs for outlets, I now suggest a 5-gang box....a two-pole switch and 4 duplexes...LOL, good luck finding a cover.

But seriously, my first suggestion, using 12g wire with sp/sw recepticle and maybe a couple surge protection outlet strips should be plenty of power, outlets and protection for a reasonable cost.

Glad to hear of no issues with phase, but Peter, did you try it both ways?

[rayban68]

I assume that you are running two breakers there, one for each set of three amps that you have shown there? Each breaker allows 1200 watts, and you have shown 1100 watts for 3 amps.

#10 is pretty big ( 30 Amps), 14 gauge wire is rated at 15A and your 15 amp breaker only outputs 12 amps, as breakers can only be loaded to 80% of their rating, unless you purchase 100% rated breakers.

Also, #10 will be a pain to connect to your breaker as this is probably the largest size that they will accept. Stick to #14 as it is more than adequate.

Chris, I am not sure that there is room in your electrical panel for soft start circuits, or if the electrical code allows that sort of thing in your panel. You'd prolly be better off with soft starts on each amplifier. Alternatively you could just put a switch in each amplifier and power them up sequentially.

x. onasis, running 3c#12 (or #14) will save some wire, but not much power. The potential power savings come from current cancellations by sharing the neutral between these two branch circuits. The current will cancel out if both loads are exactly the same, but since music is so transient, there will be very little cancellation. I do agree that if chris ma wants to set a system up like this, a switched receptacle would be much more convenient than going back to the panel to power the amp on every time.

[rayban68]

You do not need to rate everything downline of 10gauge wire at 30 amps. All you are required to do is ensure that the wire is sized appropriately for the breaker ie #14 or better for 15 amp breaker, #12 or better for 20A breaker and so on. You can run 500MCM off a 15 amp breaker if you so desired, but good luck connecting that

Now, if you want more power, you can run a 30 amp breaker and appropriately sized wiring, but you have to consider if your amplifier will ever actually draw that much power.

[chris ma]

Thanks for the input gents,

Yes I am running 2 15A breakers one for each channel, actually one channel also share with the rest of the system like DAC, DVD, active crossover. The other channel share with turntable, may be a TV in the future. If for overhead projector instead of TV then it will be a different location, no problem here except money.

Right now I am using only either the 4 classA or the 2 classAB, but as soon as I finished my H-frame dipole subs it will be used as my diagram shown. The 10awg wire are already connected to the fuse panel run through studs and mounted as wall outlets, left and right wall. I am using a 15A surge protection with 6 outlet strips each side. Mount the 10awg thru all the joice and studs on the ceiling was a very tough job indeed for this is located in the basement.

Soft start close to the panel was just a wild idea. I don't think it will work anyway.

Regards,
Chris

[x. onasis]

Not trying to be flaming here.

What I was meaning to say is that he could put in a smaller breaker on the 10 ga coming into the panel, but if he wanted to continue the circuit to other boxes or devices, the wire size can't be reduced. An electrician looking at the panel seeing 10 ga. wire must be able to assume he can put a 30A breaker on that circuit.

And I don't think it's code legal to hard wire a 15-20A device on a 30 amp circuit. Would you do it?

[rayban68]

Would you hard wire a 0.8 amp device to a 15 amp circuit? ( hint, 100 watt light bulb)

Seriously tho, no I would not use a 30A breaker if I only needed 15 amps, what I meant by using a 30A breaker, is that if you needed more power than the 1400 watts from a 15 amp breaker (say a 1 kw class A amplifier which requires 2+ kw of power) then you need to up-size the breakers and wires and so on.

If your electrician sees #10 wire and assumes that he can use a 30 amp breaker, you need a new electrician. He would have to confirm the rating of any receptacles and other loads on the circuit and make sure there are no smaller wires connected to the circuit, but I do agree that it would be very poor practice to splice #14 wire downstream of #10 wire. The opposite of this is done very often in commercial work, for example when you need to run #8 wire out to a parking lot (needing the larger wire because of voltage drops) and then running smaller wire like #12 from the junction box at the bottom of the pole to the light fixture or block heater plug.