HT Wiring Question (electrical question)

[Nik]

I am in the final stages of setting up my home theater in my living room but have a tough decision. All electronic audio/video components are running on a standard 15amp line through a power conditioner. I am wanting to install two 20amp lines (no not 220) because I will be running four Emotiva amps- 2x XPA3 & 2x XPA1. The XPA1 is a 1000watt monoblock at 4ohm and the XPA3s will be running at 400watt x2 at 4ohm and 500watt x1 at 4ohm. Until the XPA1 is released I will be running the 2 XPA3s. I have Aerius i fronts, Logos center, and Helos 100 rear- the Aerius will be replaced with Sequel 2 after I replace the panels.

So here's the question: I only have two blanks in the breaker box...
-should I run two 20amp lines with hospital grade plugs and condense existing breakers to open up spots
-one 20amp line with hospital grade four plug outlet
-one 30amp line with hospital grade four plug outlet

What other options do I have?
Thanks all!
Nik

 

[OldMonolith]

Hi Nik,

I would suggest you have more to gain from two seperate runs than one heavier guage run.

I'l look for lighter load household 15 amp breakers and move two lighter loads to one of the double breakers if it's necessary to gain a space. Electricians wrinkle their face a bit at those, but they are code and when necessary are...well...necessary. But if you have 2 opens and just add two 20's, then you might be able to avoid this.

Make certain that all outlets that the system are going to run off of, are on the same leg of the power. This is very important! Also, while looking into things, I'd suggest measuring the current draw on each main leg with normal uses and see if overall the draw is as even as it can be between legs. Sometimes, with a bit of moving things around, you can improve balance and lower noise as a result.

I think what you're saying is that you might be able to set up with the front end electronics running from the existing 15 amp circuit through the conditioner. Then you could have a split up of the amp load between two additional 20 amp circuits. That would sound like a pretty good setup to me!!

Good luck with it...

OldMonolith

 

[Burke]

Make certain that all outlets that the system are going to run off of, are on the same leg of the power. This is very important!

I have also in the process of running lines to my system. I have heard this advice before but I do not understand why this is important. (all equipment running on one leg ) I would think that it would be better to balance the load between the legs as you state in the next sentance. (ps I know that you are refering to a whole house balance)

Thanks,
--burke

 

[ScottGardner]

You want to power everthing from the same leg to minimize the possibility of ground loops.

Low current wiring is particularly susceptible to ground loops. If two pieces of audio equipment are plugged into different power outlets, there will often be a difference in their respective ground potentials. If a signal is passed from one to the other via an audio connection with the ground wire intact, this potential difference causes a spurious current through the cables, e.g.: creating an audible buzz at the AC mains base frequency (50 or 60 Hz) and the harmonics thereof (120 Hz, 240 Hz, and so on), called mains hum.

They're easier to prevent in the first place than to correct later.

 

[Nik]

Make certain that all outlets that the system are going to run off of, are on the same leg of the power. This is very important! Also, while looking into things, I'd suggest measuring the current draw on each main leg with normal uses and see if overall the draw is as even as it can be between legs. Sometimes, with a bit of moving things around, you can improve balance and lower noise as a result.
OldMonolith

What happens if my conditioner (has ML Aerius i, Logos, blu-ray, HD DVD, TV, A/V Switcher, Receiver, VHS, and cable) are on a different leg of power? Any problems with ground loops there?

I think what you're saying is that you might be able to set up with the front end electronics running from the existing 15 amp circuit through the conditioner. Then you could have a split up of the amp load between two additional 20 amp circuits. That would sound like a pretty good setup to me!!
OldMonolith

Here is the break down:
Outlet 1- 15amp: living room breaker: hospital grade outlet: subwoofer
Outlet 2: 20amp: own breaker: hospital grade outlet: 1000w SS and 500w SS Amps
Outlet 3: 20amp: own breaker: hospital grade outlet: 1000w SS and 500w SS Amps
Outlet 4: 15amp: living room breaker: PS Audio Soloist outlet: M@nster Power 5100MkII: ML Aerius i: ML Logos: blu-ray: HD DVD: TV: A/V Switcher: Receiver: VHS: and cable
Outlet 5: 15amp: living room breaker: standard outlet: automated blinds
Outlet 6: 15amp: living room breaker: hospital outlet: M@nster Power 5100MkII: Zone 2 receiver: amps: subwoofer
Outlet 7: 15amp: living room breaker: standard outlet: no use

So two individual outlets and 5 shared outlets. The room is 17x15x9.
Thank you all for your help, my project is hopefully drawing near an end! After I get setup then its on to acoustic treatments!
Nik

 

[VanDaRo]

Your rig sounds nice -- complex too. I subscribe to the theory that audio components need plenty of dedicated power and preferably originating from the same leg of your breaker box to minimize ground loops. In that respect, I think what your planning is more than adequate...

FYI, I have 2 dedicated 15 amp circuits for both amps, the pre and the CD player. The regular 15 amp circuit (and various outlets) installed by the builder is for lighting/BluRay/sat. receiver/television and Sequel IIs. It works well and never runs out of juice.

~VDR

 

[Nik]

Good god man- I hope I dont run out of power 2900watts of Emotiva power and 1300watts of sub power and other power planned (yet to purchase)
Anyone for movies at my place- just bring movies and pretty women (other than wives!!!)
Nik

 

[twich54]

You want to power everthing from the same leg to minimize the possibility of ground loops. .

The other (an equally important reason) is put your noise making devices, such as refrigarators, A/C, light dimmers, etc on the leg that IS NOT used for your Audio equipment.

 

[OldMonolith]

If electronics are DC coupled, then the difference in current tries to flow through the devices!! This makes for ugly!!

Between the various desires.... to balance current draw between legs, put devices most likely to put noise onto the opposite leg, physically make wires that limit moving between breaker positions and so on, it always ends up being a balancing act and trying to minimize issues. An amp clamp (and caution or electrician) is needed here!

But I'd put all the head electronics on the one circuit, and since you have the option, then the two independent feeds for the amps...all fed from the same leg of the power.

OldMonolith