Useful life of a UPS

[luisr]

I have a Blackout Buster UPS in my system which is about four years old. It's been on almost continuously since I purchased it. I have the computer, a 15 inch monitor, my ink-jet printer and my alarm clock (works wonders). I am asking because some time ago I got DSL and cannot put the ADSL router in the UPS. If the UPS kicks in due to a power outage or fluctuations (which are frequent lately) the ADSL router restarts as if I turned it off then on.

I recently got a replacement ADSL router from my provider due to another problem and the new one (which is the same brand and model as the older one) does the same thing when the UPS kicks in. The computer and everything else connected to the UPS continues to operate normally and it can keep running for more than 5 minutes with the monitor on.

But I wonder if the UPS is showing signs of age with this problem.

[luisr]

The ADSL router is a ZyXEL Prestige 623-41 if this is of any help.

[morriswindgate]

The batteries in a UPS are Ni-Cads and have a useful life of only a couple of years before they need replacing. It normally takes a special battery only available from the manufacture, so it is almost always cheaper to buy a new one.

[ktkendall]

We're replacing ou customers batteries when they get to the 5 year point, but we are talking the bigger UPS's with the lead acid batteries. I would check the owners manual on yours, and just out of curiosity I would try unplugging everything from the UPS except the adsl modem and pull wall power and see if it still causes the modem to restart. It may just be that you are exceeding the load that the UPS you have can really handle.

[luisr]

This is a 500 VA unit so I doubt I am overloading it unless the battery is really bad. It is not giving any overload alarm either when it kicks in.

I believe this UPS has a lead-acid battery, not Ni-Cad.

I will try that test of putting just the ADSL modem in the UPS.

[ktkendall]

You're right, a 500VA should be fine with a PC and dsl modem on it, but that is weird that everything else doesn't even burp, but the modem restarts..If a UPS is functioning correctly there shouldn't even be a burp or anything when commercial power is lost. They are supposed to run off the converted battrey dc to ac power all the time and commercial power is just serving to keep the batteries chargeed so thats why there is not even a glitch or spike or anything when commercial ac power is lost..Thats why I'm thinking that the initial draw with the adsl modem added is causing a dip enough to cause the modem to restart..Is that a crt monitor?? They draw a good bit of power..

[bailey]

on a true ups, everything is running off the batteries all the time and the line power is only charging the batteries.
so there should be no power glitches at all of any kind.

if your batteries are getting weak, then they should be replaced, I don't know of any good ups that has ni-cad batteries in them.
all I have ever seen were the lead acid type that are sealed.
batteries should be replaced every 3-5 yrs.

[luisr]

I did the test leaving the ADSL modem alone in the UPS and it restarted just the same when unplugging the UPS from the wall. I will probably take my modem to my brother's who also has DSL and just got a brand new UPS and try it there.

[edfair]

You probably have equipment that is sensitive to the type of power. Unless you bought a special full time conversion unit you have output that goes choppy when it loses input. Definitely not sine wave.
As far as the batteries, some die early , some don't. Test them by pulling input power and see how long they hold. Just don't have jobs open.
Batteries are more common in hardware stores recently. And electronic parts stores, and even in battery stores in some of the larger cities.

[luisr]

I think it is the sensitivity thing because I replaced my existing modem with the exact same brand and model and it does the same thing when in the UPS.

[ktkendall]

Good point there I do remember that many of the basic UPS's that are sold that for home use that the averagePC user can afford do not put out true sine wave, but a square wave.

[luisr]

BUMP!

Finally got to test my ADSL modem in a different UPS. A bigger UPS for that matter. The result??? Same thing. Modem resets whenever the UPS kicks in.

It appears like this modem is ultra-hyper sensitive to the very very very brief time it takes for the UPS to switch from line power to baterry power even though the computer is not affected.

[bailey]

a true ups does not do any switching, everything is running off the batteries all the time, the only thing the power line is doing is charging the batteries

a stand-by ups does run off the power line and switch to the battery when tha power is lost.

I have a cable modem, router, switches, large computer, monitor,printers and light all running on my 1100 va ups and when power goes off, I don't even know it.

I even have a older apc ups that was tossed out many years ago, I salvaged it from the trash ben and took it apart and found the batteries were bad, as a experiment I hooked up a car battery to it and set the whole thing on a shelf under my bench, and powered the outlets on my work bench with it and it has been running great for many years that way.
I have a total of six ups running my whole shop.

[pillainp]

I'm still using my APC 500VA UPS (purchased in August 1998). It has never needed service, and since the PC is on all the time, it is always loaded as well. It still gives me 5-10 minutes backup, and I am not asking it for any more.

[diver203_98]

I agree with bailey, in that you should replace the battery every 3-5 years. Over time they build up a memory because they are NICad batteries. But most newer ones use lead acid betteries, and there is no memory to worry about.

Also something to remember and check out:

Usually there are only 3 or 4 back-up sockets, and the rest are only surge suppressed. So I would check to see if your DSL modem is plugged into a backed up socket and not just the suppressed socket. If your DSL modem is on a suppressed socket, when your UPS trips, it will restart as if it were only plugged into a wall socket. And if it is in a backed up socket, it shouldn't restart, as it should keep running without a glitch as the others, like your monitor and computer.

[luisr]

I am aware of all that. I don't think my UPS has Ni-Cad batteries. Otherwise it would have died long ago. The other UPS where I tested the modem is brand new and is bigger than mine, so the battery issue is not the reason.

And yes, my UPS has protected and unprotected sockets. I cannot test using the unprotected sockets because the only way I can test it is by unplugging from the wall - no test switch in this thing. If I were to test using the unprotected sockets the modem would just turn off and not restart when I unplug the UPS.

The UPS can still hold my PC with monitor on for more than five minutes without problems.

I have concluded already, based on the latest test I did, that the modem (this brand and model) is to blame - super-hyper-ultra sensitive to the power switch. For this reason the modem is plugged to the wall directly. Interestingly enough I am yet to see this thing restart or even hiccup when there are power fluctuations that cause the UPS to activate briefly.

[bailey]

I supposed that it could have a large capicitor in its power supply that will maintain the connection for breif moments.
and the voltage output is not high enough to do it job correctly on the ups.

[mairving]

Originally posted by morriswindgate The batteries in a UPS are Ni-Cads and have a useful life of only a couple of years before they need replacing. It normally takes a special battery only available from the manufacture, so it is almost always cheaper to buy a new one.

This only applies to the cheap UPS's. I have a $300 UPS and the battery only costs about $50.