Evolution

Recently I've been having some brief power outages at my house... a few seconds here or there. I'd like to get a backup battery/surge protector that will work with my HT and game devices. The total power draw is under 450Watts. I was looking at the Back-UPS ES 725 from APC, http://www.pcmall.com/pcmall/shop/de...CNETSHOPPERPC. But the tech at APC said I shouldn't use the Back-UPS because it only approximates a sine wave signal whereas the Smart-UPS uses a true sine wave. And most of the equipment in question (she said) needs a true sine wave. Is that true though? The difference in price between the 2 units is over $150, so I'd rather not buy the Smart-UPS unless it's necessary. Any help (or other suggestions) would be appreciated. Thanks.

X

Exactly what are your HT devices?

Evolution

Yamaha HTR-5240, Mission 70as sub (running through the Yamaha), Sony Wega KV27FS13, and Pioneer DV563as. That's it. Small bedroom-sized setup. Nothing elaborate.

OldDude

I have an (older) Back-UPS on one computer, a Smart UPS on the other. Both claim a good sine wave approximation. I think she gave you bad info. The Smart UPS has a link to your computer and software to initiate computer shutdown, when the battery gets to a certain state of charge (usually about 50%, but you can adjust it). If you aren't there, the computer will shut itself down, before battery goes dead. You probably can't use that on a HT, not sure about game boxes. (You can use the Smart UPS, there is just no where to connect the port to, but it will still power the HT stuff until battery runs down)

The sensors, communication (serial or USB) and software account for the difference.

X

A backup UPS should just pass the line power through, unless it also conditions it. But conditioning it with a lower-priced UPS probably wouldn't be doing enough to change the sine wave.

A true UPS would always output power through its inverter and that's when you would have to be concerned. We're not talking a true UPS here.

It's only when your power is out and you are running off UPS power that you would have to be concerned about the shape of the wave and you'd probably want to turn off your equipment at that point anyway. I would think the biggest effect of a bad sine wave would be bad sound, not destruction of your equipment.

I would probably get a higher wattage UPS though. The way they rate that stuff 450 is kind of puny for a 27" TV that draws about 160-200 watts on its own.

Evolution

Hmm... I have a Back-UPS on my computer and it also interfaces with the computer to initiate shutdown when the battery's low. Is there any other major diff between the Smart and Back? They both approximate sine waves? I guess the Back-UPS should work fine then with the HT gear? I'll wait to hear from Mr. X I suppose... Thanks for the information though. I'm always weary about CS suggesting higher-priced products.

Evolution

Well according to Sony, the Wega consumes 170... the Yamaha and sub are 220... and the DVD player is 14. So I'm only at 404 Watts. Is the 46 enough headroom? They can't be rated that poorly. Thanks for the help by the way.

X

Maybe it's VA I'm thinking of. For instance, a 800VA UPS I just looked up is rated as 450 watts. So I guess as long as you're talking real watts you're ok.

However, equipment draws more power when it starts up. You are within 10% of the UPS's max wattage which won't let it run for more than a very short time on battery power. I prefer not to go over 60% or so of max, but somewhat higher is probably ok.

Check what it says about how long different loads will run on battery power.

Evolution

Thanks for all the advice. I appreciate it. As you said, I probably would power down the equipment if it's more than just a few second outage. My primary concern was an approximated sine wave causing damage to any of the gear. As long as that's not an issue, the battery life isn't a big deal. Thanks again.

gotapex

Actually, I believe only the SmartUPS's 700VA and above use true sine waves (or at least that's how it was a little while ago). Most HT electronics definitely prefer true sine waves to stepped.

The problem is UPS's don't "burst" well. So, when you get to a particularly loud passage of music, your system will draw more than the average wattage. If you only plan for 800VA for a 450 average watt system, you may bump up against this ceiling of sorts.

OldDude

I don't have a catalog or anything. Before they coined "Smart UPS" I think there may have been a Back UPS Plus or something that had a serial interface to computer. Mine is vanilla version and does not.

If you already have Back UPS, just give it a try. Try the APC website; you should find the specs on all models. Their long names is American Power Conversion, not sure if website is that, APC or APCC with www and .com wrapped around it.

Here's their product page
http://www.apcc.com/products/category.cfm?id=13

What run time do you need when power is out? The power rating is tha max watts the inverter can handle, but the battery only gives 15-20 minutes run time at that power. If you want more run time, you need higher power rating (too bad you can't just buy bigger battery).