Uninterruptible Power Supplies

Lead me, Herdmasters.

I need a small UPS to go between a little 1000 watt Honda briefcase generator and our new event management system, which currently consists of a couple laptops, a wireless router, and a PoE switch. At our first event, we kept having little power drops which didn't really affect the laptops of course, but played hell with the wireless.

Most of the reasonably-priced UPSs seem to have the dreaded "stepped approximation of sine wave" output. Is this an issue? It's $250+ for one that has "quasi sine wave" output.

Anybody have recommendations for a smallish, lightish unit in the 300W/500VA range? I'm looking at this one. Thanks.

APC makes good stuff so if it can handle your power requirements it should be OK for you.

I run 500W APC units on everything I want to keep. Cuts way down on replacement costs. One of those should work fine for you and are way under $250.

In reply to Dr. Hess:

Yeah, that's about what I'm looking at. My question was about the details of the power output, and how clean the sine wave needed to be.

small units are only good for covering short brown-outs on smaller to medium loads

you have to total up your wattage of the equipment you're going to connect before you can really decide what capacity you need.

Yeah UPSes with true sine wave output are big $$$($). A small APC unit will do the job. The squared pseudo-sine-wave only happens when running from battery power, and in my experience it doesn't cause problems.

(I have all my home computer equipment on UPSes and they get used often).

Cool, thanks. This isn't running a ton of equipment because the laptops have their own batteries and will mostly be using it for surge protection. I really just need it to condition power for the router and PoE switch, when the generator hiccups or quits.

My wifi/router runs off the APC's, no problem. They are designed for computer equipment, so I figure they are "close enough." I bet if you put a scope on what's coming off that generator, you would be "shocked."

Also, the wifi at least will probably be running off a wall wart, right? That's either going to kicking out DC itself or it will be converted to DC in the wifi, then regulated to whatever the chip set runs at, so wave form at the input side is not really going to matter all that much. I don't know what a PoE switch is, but I bet the UPC won't bother it a bit. When we lose power, my 500 watter will run my desktop, monitor, wifi and cell phone for at least 10 minutes. Oh, and expect to replace the battery yearly if you use it every day.

For your application, I would plug the two laptops into the "non UPC" side of the APC unit, getting the surge suppressor value out of it, and the non-battery operated equipment like the wifi on the UPC side and you'll never have an out.

Dr. Hess wrote: I don't know what a PoE switch is, but I bet the UPC won't bother it a bit.

A network switch that also puts out Power...over Ethernet

You're right that the AC-DC adapters will smooth out the square waves before they touch any of the electronics which all run on DC power, but it is theoretically possible that the square waves could cause a problem for the adapters. When my stuff is running on battery power, the only difference I've noticed is that computer PSUs make a slight hissing sound.

APC to your rescue! I use one like This at home. It is not light, however I see no power interruptions when there is a minor surge unlike my inexpensive APC battery back up. YMMV.

EX APC employee here. Here is the issue with the smaller units like the ES series, It will only kick in with major drops in power.

It sounds like you are looking to condition and correct minor brown out situations. That means you want something with Boost and Trim Automatic Voltage Regulation. That will be the pro series.

This should do it for you at a good price:

http://www.amazon.com/APC-BR1000G-Back-UPS-8-outlet-Uninterruptible/dp/B0038ZTZ3W/ref=sr_1_3?ie=UTF8&qid=1429042963&sr=8-3&keywords=br1300g

For a pure sine wave output, Cyberpower makes a good one:

http://www.amazon.com/CyberPower-CP1500PFCLCD-Sinewave-Compatible-Mini-Tower/dp/B00429N19W/ref=cm_cr_dp_asin_lnk

It's the energy star power supply that may be the issue. If you have an Active Power factor correction power supply in your equipment, use the cyberpower.

Great info, thanks again.

We've been running a very similar setup for several years (including the 1000W Honda generator) and use the UPS from your first link. No problems at all. It's definitely worth it for when the generator runs out of gas or someone trips over the extension cord.