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Tweakers' Asylum Tweaks for systems, rooms and Do It Yourself (DIY) help. FAQ. |
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In Reply to: RE: Information I can't find on AA about Dedicated AC lines posted by Coffeecupman on January 9, 2008 at 02:31:50:
>> I'm not buying nice power cords and then feeding them through a 10 buck 15A breaker. <<
I understand exactly what you mean, but don't get sucked too far into Audiophile Myth-land. A little bit down this page is a post from someone complaining about the thin metal and flimsy construction of a residential-grade circuit breaker. All this proved to me (again) is that way too many audiophiles don't know the first thing about electrical systems, and should not be messing around with them.
A circuit breaker is a protection device. It's there to keep your electrical system from killing you and/or burning your house down. Yes, I know this is obvious, but for some reason the "obvious" part is the last thought many audiophiles ever give to this critical component. Here's the rest of the story:
In order to provide that protection, a circuit breaker absolutely MUST be the weakest link in the chain. Basically it's designed to fail before other components in the chain do. If it were a robust device, it could not act as the sacrificial lamb, and that would mean disaster. A circuit breaker MUST have thin metal and flimsy connections. When an electrical fault occurs through overcurrent, short, whatever, heat is generated. This is why houses tend to catch on fire - the outlet or wire gets so hot that it or the surrounding material burns. Most circuit breakers are thermal devices, which means that they will trip when they get hot. If the circuit breaker used thick metal and sturdy connections, it would heat too slowly to trip when a fault occurs.
The other thing to think about is that it's an electrical SYSTEM. The components are designed to be used together. A system designed for residential use contains multiple components designed for residential use. If you introduce individual components that are not designed for residential use into a residential system, you create a system that no longer meets specifications. Behavior of the system may be unpredictable. You may think you are protected, but you may not be. So, it's a bad idea to go outside the design parameters and specifications of a residential system by introducing components not designed for that system.
>>but even my limited experience has taught me that some things you just have to find out for yourself.<<
Yes, but keep in mind that you're talking about electricity. Finding out for yourself could mean property damage, injury, or death. The chief cause of home electrical fires is faulty or poorly installed electrical wiring. Household electricity has been with us for so long that most people take it for granted, and often forget that it's a proven killer. It should be treated with absolute respect and the utmost in care.
>>It would be easy enough to swap the breakers back to residential ones, wouldn't it? I won't throw out the old ones.<<
See above, and also consider that commercial/industrial components may not even be compatible with equipment that you're legally permitted to install in your home. That's what I meant. If you want to use commercial/industrial breakers, you may have to install a commercial/industrial load center. I don't think that's a good idea.
>>> Probably not. Unless you have gear that specifically requires a 30A >>>circuit (these are quite rare), there's no need for it.
>>Well, if they exist at all, I'd like to be prepared for them.<<
Since the trend is for MORE efficient appliances, not less efficient, it's doubtful you'll find much of anything new that would require a 30A circuit. There are a couple of older power amps I'm familiar with for which the manufacturer recommended a 30A circuit, such as the Mark Levinson No. 33 and No. 336, but these were unusual designs. Your JC-1s are more efficient - per Parasound's specifications, each amp will not draw more than 10.7A at full load. You won't be running them at full load.
>>is there really any harm in too much headroom if it doesn't cost too much extra?<<
Actually, there can be. When a load center is installed the electrician will attempt to balance each leg in order to create a symmetrical load on the incoming service. The way this is done is to populate each leg with breakers that are evenly distributed, kind of like this:
Leg1 Leg2
50 60
30 30
20 20
20 20
20 15
20 15
15 20
15 20
15 15
15 15
If you run a subpanel, you will put the breaker on one leg. If you run individual lines, it's best to put them all on one leg. If you vastly oversize your setup (i.e. a 100A sub-panel), and then only use say 12A of that capacity, you'll be putting an asymmetric load on the legs. An extreme asymmetric load is bad - bad for your appliances, bad for your power bill.
>> part of my reason for more dedicated circuits is the increased isolation from one component to the next. I understand that using separate breakers for these components can reduce AC line crosstalk. Am I wrong about that?<<
It's true, up to a point - which is why I'm running multiple lines into my dedicated room. It's not a panacea, though. Keep in mind that the electrical system in your house is a bus, and everything rides the bus.
Good luck with your project.
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Follow Ups
- RE: Information I can't find on AA about Dedicated AC lines - racerguy 14:05:30 01/09/08 (1)
- new post above - Coffeecupman 20:55:39 01/15/08 (0)