Reliability of Small Uninteruptable Power Supplies?

I use a ES for over 10 years now. 300 Watts. The batteries were gone after 1 year, but I have wired it to a battery of 12 Volts 100 Ah. When I have a power outage, happens frequently, I switch off the computers within 10 minutes and have a 10 hours lights working inside the house on that UPS.

Most UPS have small batteries inside and do not provide a sinus. It work a while as long as the UPS gets a stable DC power supplied, which is not often the case with the smaller sealed batteries. The waveform starts changing, amplitude is lower, the inverter switching device dissipates more etc.... It is also difficult to predict what the UPS does to your batteries.

I think what you've done is the best long term solution.

But, we have better quality power here than you do there.

I wonder if anybody makes a UPS with dual batteries so one can be fully cycled, discharged/charged periodically, with the other battery on-line, to extend the life of the batteries?

It may not be worth the extra cost.

"When I have a power outage, happens frequently, I switch off the computers within 10 minutes and have a 10 hours lights working inside the house on that UPS. "

dvmdsc

How do you make that connection?

Manually, with a semi permanent drop cord to standing lamp fixtures. About 4 pieces of 7 watts. (LED)

It sounded as if you have the whole house connected to the ups. Here in the hurricane zone I used to use a generator but gasoline is too expensive. Your method would work for lts, tv and a fan. Problem would be recharging the battery. Would a 12v die hard work?

Yes, they only have a little more leak current compared to Sealed deep cycle what I use. The lead acid sealed batteries for UPS are similar charging like regular batteries re: die hard (automotive)

Normally, hurricanes here last, say 6 hours. But Frances came to visit us for 36 hours in a row and left the place 3 months powerless. Required capacity is your call. Rgds. D

Hmmm...these small UPS do have small batteries. No reason I couldn't put a bigger battery outboard. More up-time and maybe it would cure whatever is killing them. But the UPS charger is sized for the small battery. A bigger one might not get charged properly. Might even hurt the unit.

I smell planned obsolescence.

Stop thinking and start acting is my advise in your case.

The unit I have is serial regulated and current limited: the battery gets not what it is asking for. Only that much little the charger print supplies. They all have this circuit, since the batteries are permanently monitored.

It just takes longer to charge the battery, but most of the time we have power available.

Now I told you plan A

Plan B is 4 similar batteries, not connected to the one I spoke about, with a charger inverter of 500 watts and 500 Watts 12 V solar panels. This unit powers the CCTV circuit directly from the battery, at night also the IR lights.

However, I need to help the batteries charge now because of inadequate solar production. Works well in summertime.

How does obsolescence smell, just for the record?

A small charger will just charge a big battery slower.

It will actually get a bigger capacity in the end, though you may not actually notice that. The faster you charge, the lower the capacity achieved.

As long as the charger does not overcharge, it will also increase battery life due to it not being charged as fast.

A leisure type battery will usually give a longer working life as it accepts a deeper discharge with less damage. Pick the biggest one you can afford!!!

SSCpal,

Possibly your problem is very dirty power coming in. It could be frying the surge suppressors on the input end and then leaving the UPS electronics wide open for failure. I suggest you look at a surge suppressor for your whole house and install it at the service. One I have used for a long time is from SquareD (SDSA), but many others exist. Costs will vary anywhere from about $40-75 all the way up over $1000 for VERY good ones (probably overkill for typical locations).

Otherwise, look at a higher-quality and somewhat more expensive UPS. This may get you past the cheaply-designed low-end ones.

--John M.

Thanks for the ideas. A whole-house protector sounds like good insurance for all the electronics we have now. And I have just started looking at better UPS's. I've learned the cheap ones put out stepped approximations of sine wave, which some computers don't like. At roughly 2x the price one can get an UPS with true sine-wave output. And we'll still only talking $200-$300 for one to handle my A/V system.

A few decades ago I put one on the service for a public swimming pool. Before this I was replacing 2-4 GFI breakers every spring; afterwards I didn't have any fail in 5 years. Lost some business, but gained a lot of appreciation. --John M.

Battery often goes down. MOSFETs also age out. NASA does not use same things and also many others have to pay for special long lasting parts.

Communication people use excellent UPS that last over 5 years. I used some special one that lasted 10+ years due to special battery and superior inverter designs.

These days you can get some of these that can last 30 years. All unmanned stations use such things so simply dig them out.

I have owned a few APC units in the size range you are talking about; and have experienced reasonable lives out of each (4 to 8 years).

Many of us have over-loaded these units, especially with things like 21 inch CRT monitors, watch loading levels! My last one failed 2-3 years ago, and I have not replaced it, but it's load had grown over the years to 2-23 inch LCD displays, my notebook, my company notebook, printer, power supplies for ... a desk phone, IPad, IPhone, Kindle, cable modem, and hub. Likely too much, considering little was ever turned off.

It is also amazing how long ago we purchased some devices ... I sharpie the date of purchase on the bottom of electronics these days, and my personal notebook sitting here is almost 10 years old ... I would not have guessed that.

Check out this place and their Inverter Chargers. You can keep your devices connected to the inverter since it has a built in transfer switch.

http://www.theinverterstore.com/inverter-chargers.html

Tom

The inverters shown at your site would be just what I was looking for. I would need only a 1000 - 1500 watt to do what I want. Thanks.

Those are nice inverter chargers to use with things like a sump pump. The larger ones (2000W plus) could and are sometimes used for UPS for a furnace. Although I have generators for my houses, I'm seriously thinking of doing the inverter charger for the furnaces if I travel away from home during bad weather.

I've had similar experiences. One failed when a sink overflowed and the floor got wet.

The last one I bought never worked right out of the box! I did properly connect the battery, and let it charge for 24hrs, but it would not power a simple lamp. I never took it back, since I Had not found time to read the manual; still haven't...

My most important computer is a laptop, with 6-8 hrs of battery life, so it is its own UPS.

I see no need to waste money on a UPS as I decided a long time ago, that if I ever needed mains when the mains had dropped, I would simply make my own.

I have been designing and building 12 volt lead acid battery chargers for around 15 years or so, so using one of them to correctly charge a battery is no problem. No overcharging.

The 12 volt 120 A/H leisure battery from my caravan is easily removed in about 2 minutes.

I have a small 12VDC to mains inverter for a camping TV and SAT receiver, which produces 1 amp at 230 VAC.....had it years. Works great.

My pellets stove needs about 100ma when running and it can be started without using the heating element by simply unplugging the element and using a fire-starter....good design!! Not all can, mine has no safety switch on the grate door!!

If I need more power I just have to buy a bigger inverter unit plus bigger battery......problem solved.

The only change I would make to that for a UPS for a PC, would be to buy a "Pure Sine" inverter......mine isn't.

Properly organised with an intelligent charger plugged in, it could be put somewhere and left waiting for the blackout....staying always fully charged!

the problem I would bet is old electrolytic caps in the inverter section that dried out and took a bit too much heat. these cheap UPS's were designed to be disposable so the caps are the cheapest that money can buy. you MIGHT try replacing every cap in the unit with the good 105C temp rated, low ESR caps and see if that ressurects them. It might not, they might have taken the MOSFETS out with them when they fried, but it might be worth a shot.

Good idea. They are worthless now, so might as well crack them open and take a shot. Would be nice to know what the bleep happened.