I'll try and make this as quick as possible.

I bought a new A/C last week. Last night blew a fuse/circuit breaker. Decided I should buy a UPS for HT setup. Looking for suggestions for a well priced unit that has voltage regulation. Will something like the APC H15BLK be enough? It appears that my current setup has the items below all plugged in through the same circuit (but different outlets), will a UPS help with preventing blown fuses? Thanks!


- Mini-fridge, PC Ultra, A/C unit, HK 7200, X-Box 360, Wii, Oppo 981, and cable box.

no... move the A/C and possibly the fridge to a different circuit.
Optimally, you should have you A/V gear on a dedicated circuit.

You don't say whether the branch circuit is 15 or 20 amps and what event trips the breaker, but let's assume 15 amps, that it is a breaker not a fuse and that the AC startup is the likely cause.

AC units can have a heavy in-rush or startup current draw, and for that reason breakers are designed to pass short term currents higher than the rated current. If the breaker trips it could mean that--

you have a bad breaker (it happens and they are easily and cheaply replaced - most snap in and out) or

your circuit is at or near capacity or

a combination of both.

Check the back plates on all the devices and add up the watts (if given in amps multiply amps by the line voltage to get watts). Do not forget to include any lights that may be on the same branch, or devices in other rooms. This is a working approximation of the actual load, because it ignores something called the power factor, but it should be good enough.

A 15 amp circuit at 120 V can deliver about 1800 watts. It should be able to deliver between 125 and 150% of that for brief periods. Some say that as a rule of thumb you should not load circuits to more than 80% of rated capacity.

If the total demand you calculate is less than 1800 watts, try replacing the breaker. If the total demand is near or greater than 1800 watts you need a 20 amp circuit or another 15 amp branch.

An UPS unit is not the solution. A dedicated circuit is not needed.

A dedicated circuit is not needed.

Would you really recommend having a refrigerator and an A/C on the same circuit as your A/V gear? :D

I know I wouldn't.

Move the offending device(s) to a different circuit or run a new dedicated circuit for the A/V gear. IMHO

Wow! Thanks so much for your quick responses! I'll definitely be lookin into this when I get home this evening.

If I exceed the 1800 watts and require a 20 amp circuit...is that something that an electrician could take care of or does that just mean I'm SOL?

Would you really recommend having a refrigerator and an A/C on the same circuit as your A/V gear? :D

I know I wouldn't.

Move the offending device(s) to a different circuit or run a new dedicated circuit for the A/V gear. IMHO

I'm having an electrician come out today to see what my options are since I really don't want to "move" my mini-fridge or A/C to a different room and there appears to really only be two circuits available. I agree that having my A/V gear linked with a mini-fridge and an A/C really isn't too great of an idea.

I wonder if an electrician can just add a new circuit or what... Hopefully it costs less to have the electrician do this than it would to buy a UPS. =)

A box, recepticle, xx feet of romex, wallplate, and breaker. And again, a UPS will not keep the breaker from tripping if the circuit is overloaded/stressed.

Best case... if your wiring is 12/2 with a 15 amp breaker, all you may need to do is add a 20 amp breaker. But don't count on it. ;)

- Mini-fridge, PC Ultra, A/C unit, HK 7200, X-Box 360, Wii, Oppo 981, and cable box.


That circuit is way overloaded. Why not plug in an iron while you are at it!

That circuit is way overloaded. Why not plug in an iron while you are at it!

Well, I didn't realize the mini-fridge and the A/C unit were on the same circuit until this morning when I had no power. I didn't actually witness what made the circuit trip but I've been cautious about only using my A/V gear while the A/C is either in fan mode or completely off. I can only guess that last night the a/c kicked on at the same time as the fridge did. In either case...the electrician coming by today will be helpful in determining the best course of action.

A box, recepticle, xx feet of romex, wallplate, and breaker. And again, a UPS will not keep the breaker from tripping if the circuit is overloaded/stressed.

Best case... if your wiring is 12/2 with a 15 amp breaker, all you may need to do is add a 20 amp breaker. But don't count on it.

So is that something I could do? If I had an electrician do it...any idea on approx. cost? Thanks again for your continuous help!

Could you do it? Depends on your skill.
Is it legal? Not really. You should have a licenced electrician and sometimes "pernits". But many have probably done it themselves. ;)

Approx cost? Materials <$50... labor???? That depends on your electrician. Cash always works best. ;)

Could you do it? Depends on your skill.
Is it legal? Not really. You should have a licenced electrician and sometimes "pernits". But many have probably done it themselves. ;)

Approx cost? Materials <$50... labor???? That depends on your electrician. Cash always works best. ;)

Hmm...took an extended lunch and i just wasted 2.5 hours waiting around at my house for an electrician to not show up...lame. :mad: DIY is seeming nice right about now.

Hmm...took an extended lunch and i just wasted 2.5 hours waiting around at my house for an electrician to not show up...lame. :mad: DIY is seeming nice right about now.

Ah, he must be from the same guild as my guys.

Ah, he must be from the same guild as my guys.

I called another place and they had a guy out at 6:30pm. I was totally impressed with them coming by "after hours" to give me a free quote. Anyway, the overall cost would come out to $600 thanks to the damn box being on the opposite side of the house from the A/C unit.

On the plus side, I found out i have a 20amp circuit. yay! =P On the downside, I found out my A/C sucks up 1400 watts! gah! the mini fridge runs off of .9 amps, and I never got around to seeing how much power my A/V gear uses. I can't afford the $600 on the electic work right now, so i'll just have to be careful for now.

Could you do it? Depends on your skill.
Is it legal? Not really. You should have a licenced electrician and sometimes "pernits". But many have probably done it themselves. ;)

Approx cost? Materials <$50... labor???? That depends on your electrician. Cash always works best. ;)

I don't keep track of the NEC, but I've always been of the impression that a homeowner can legally do his own wiring, but cannot (legally) do it for someone else.

Even though I think the homeowner can do the work, it's supposed to be inspected by a pro.

And yes, in most places one is probably supposed to get a permit too.

Around here, it is perfectly leagl to run my own wiring, and you can run it for others too. BUT, you must have a permit, and it must be inpected by the county's electrical building inspector. You need the permit and county inspection even if you hire an electrician.

1400 watts for an A/C doesn't leave much for anything else. That thing really wants its own circuit.

And, as everyone else has said, a UPS will not prevent the breaker from tripping; it will just make your gear keep running when it does. Although no affordable UPS will let you keep running your A/C when the breaker trips, so don't plug that into the UPS or you'll overload the UPS.

Actually no, you'll kill the battery. it will probably only run a few months. there's a reason why UPS manufacturers state not to stick laser printers on UPS units.