UPS recommendations?

Discussion in 'Dell' started by Steve, Jun 26, 2007.

  1. Steve

    Steve Guest

    Ran across this info, does it seem about right?

    A typical computer with a 15-21 inch LCD monitor will be well
    protected with a 500VA UPS. A larger monitor and extra peripherals
    such as powered speakers, cable modem, wireless router or external
    DVD, CD or hard drives, require increasing the UPS to 650VA or larger.
    To protect just the computer, excluding any peripherals, a 350VA is
    acceptable. You can expect to pay around $40 for a 350VA UPS and
    upwards of $400 for a 1500VA UPS.


    Men occasionally stumble over the truth,
    but most of them pick themselves up and hurry off
    as if nothing ever happened.

    ....Winston Churchill
    Steve, Jun 26, 2007
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  2. Steve

    RnR Guest

    I've got several ups's but I don't claim to be any guru on the
    subject. That said I have read that 350VA is probably the minimum you
    want. I seem to recall seeing most often 500VA to 750VA on sale so I
    gather this is the sweet spot for typical users. Of course there are
    others but I don't see them advertised as much. I haven't kept up on
    prices so I can't say for sure but my guess is your numbers seem
    reasonable. Of course you can shop on line to get up to date costs.
    Do keep in mind that you don't have to have all your stuff plugged
    into it and excessive VA will give you more battery time which you may
    or may not need. One other thing I'd consider is whether the battery
    in it can easily be found so when it comes time to replace it, you can
    do so easily. Also you might want to know ahead of time, what the
    battery cost will be (just for peace of mind; cost might change years
    later and don't be surprised if the battery cost is 50% or greater vs.
    the entire unit cost). Last, I've read that the typical ups battery
    lasts about 3 or 4 years (of course ymmv; mine are too new yet to tell
    you but I noted the date on them).

    One question I have for someone else is, how do you know when your
    batteries are going down? Do you begin to see less reserved battery
    time or do they suddenly just show zero reserved battery time??
    RnR, Jun 26, 2007
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  3. Steve

    olfart Guest

    Many of them have an audible warning and those with installed software will
    tell you battery condition and remaining life. At least my APC 1200, 1000
    and 350 all do that.
    olfart, Jun 26, 2007
  4. Steve

    RnR Guest

    thanks for the info. I'll check my APC installed software for the
    RnR, Jun 26, 2007
  5. I think that those recommendations are on the light side. I'd go for
    600 to 800VA for a full system (computer and monitor). That said, I've
    grossly overloaded some lower power UPS' and never had them shut down
    because of it.

    I usually get 350VA UPS' for $30 or less (less right down to "free after
    rebate"). I've usually been able to buy 500 to 750VA units. I did
    manage to pick up a 1,500 VA unit for $50 after rebate (Office Depot in
    February ... I'm having trouble getting the rebate). These things do go
    on sale, and you can get great prices.

    Another option, buy a unit on E-Bay that needs a new battery, and
    replace it yourself (have it shipped without the old battery to save
    shipping cost).
    Barry Watzman, Jun 26, 2007
  6. Pull the plug and test it. I don't think that any of the "no load"
    indications are worth much. I test with incandescent lamps that have
    150 watt bulbs in them (or two such lamps, sometimes, for higher rated
    Barry Watzman, Jun 26, 2007
  7. Steve wrote:
    I picked up a APC Back-UPS Pro 500 from Fry's for about $30 (no mail-in
    rebate), and I am happy with it. It's currently connected to an
    ultra-low power desktop which runs 24/7, a 20" display, an external HDD,
    and I use Network UPS Tools (NUT) in Linux to automatically shutdown the
    PC if on battery for more than 5 minutes. Be sure to test the battery
    out every few months (I usually bring the PC down to a low run level
    with the volumes unmounted and pull the plug, but if you're running
    Windows, you might not want to use your PC in the test).
    Nicholas Andrade, Jun 27, 2007
  8. Steve

    Journey Guest

    I haven't purchased one yet (I will soon), but I won't buy one unless
    it has auto-shutdown software in case of a power outage. I leave my
    desktop on all the time and it's likely that in case of an outage I
    wouldn't be home.
    Journey, Jun 27, 2007
  9. Steve

    Steve Guest

    Ok, here's a stupid question - other than being a better surge
    protector, what does a UPS do? Does it come into play only if you
    happen to be working at the computer when a surge hits? Then you get
    a couple minutes to save your work and log off? Any other benefits?


    Men occasionally stumble over the truth,
    but most of them pick themselves up and hurry off
    as if nothing ever happened.

    ....Winston Churchill
    Steve, Jun 27, 2007
  10. Steve

    RnR Guest

    At this point I think you need to either use or Google
    to look up UPS and let them explain what it does/doesn't do.
    RnR, Jun 27, 2007
  11. Steve

    Ron Hardin Guest

    They're useful without autoshutdown. The killer for data is a double
    power hit, where the power goes off, on, off, on, off, and catches
    the computer in a really bad state on the second one. A UPS turns
    off cleanly once.

    And of course you can work right through momentary power hits.
    Ron Hardin, Jun 27, 2007
  12. Steve

    Notan Guest

    My system's primary UPS is an APC Smart-UPS 1000XL... With my current
    configuration, I have >100 minutes of battery runtime, with the option
    of adding additional batteries for even more.

    Working in the field of organ transplantation, it's critical for me
    to have reliable Internet and data access.
    Notan, Jun 27, 2007
  13. Steve

    Ron Hardin Guest

    Explain the ``additional batteries''

    The problem with wiring in a deep discharge marine battery is that
    the charger doesn't necessarily work right with it. Does this thing
    have some arrangement that works?
    Ron Hardin, Jun 27, 2007
  14. Steve

    Notan Guest

    Notan, Jun 27, 2007
  15. Steve

    Ron Hardin Guest

    Four of the 250 pound batteries would give you a really nice run time of 3 days.

    I think it's all going the wrong direction. What you want is a UPC that
    can safely keep an ordinary deep-cycle marine battery charged, and hook
    one up. Since it's a single 12v battery, it has to be a low power UPC,
    say 400w is fine (otherwise you draw insane currents from a 12v battery).

    When the battery dies, just get another from Kmart, or steal from your car.
    Ron Hardin, Jun 27, 2007
  16. Steve

    george Guest

    I just replaced the batteries on 3 Belkin UPS's. If you can measure
    dimensions, you can save a lot by purchasing your replacement batteries from
    an electronic supply house (I used either Digikey or Jameco, I forget which)
    rather than the manufacturer. Turned out to be the exact same brand and
    model, too. FWIW, all three UPS's were about 4 years old. I also use
    APC...they are newer and so far no battery replacements on them.

    For the OP: make sure you get shutdown software as well, otherwise your UPS
    won't do you any good on an unattended PC or if you have too many to shut
    down manually.
    george, Jun 27, 2007
  17. A UPS actually MAKES electricity, so the computer continues running even
    if there is a total failure (even if you pull the UPS plug out of the
    wall). This gives you time to shut down normally, and prevents data
    loss due to power failure in the middle of disk writes, etc.
    Barry Watzman, Jun 27, 2007
  18. Steve

    Notan Guest



    And I always thought it was just a device used to manage energy stored in
    a battery.
    Notan, Jun 27, 2007
  19. Steve

    w_tom Guest

    Your original citation ( is classic myths. That
    author clearly does not have electrical knowledge. For starters,
    brownouts do not harm computers. One power supply function: provide
    all voltages to computer (even enough to perform a startup) when
    incandescent bulbs are only 40% intensity - a severe brownout. If
    power supply cannot maintain voltage (lights dim even lower), then
    power supply 'system' simply shuts down computer. No damage. Even
    demanded in Intel ATX specs and was required in 1970s industry
    standards. Just another in a very long list of functions inside a
    power supply even 35 years ago.

    What does a plug-in UPS do? It provides power long enough to save
    data. Typically has no hardware protection functions. It connects
    computer directly to AC mains when not in battery backup mode. Does
    that relay perform surge protection? Of course not.

    It does claim surge protection. But color glossy sheets are where
    half truths are promoted to the naive. For example, it does not
    protect from a type of surge that typically does hardware damage. Its
    protector component is typically so small as to be near zero
    protection. But it does have protection. Just enough to post a half
    truth on color glossies.

    Go to its numerical specs - where useful numbers are found. No
    numbers? Then a fact does not exist. Specs do not list protection
    from each type of surge and numbers for protection? Otherwise you
    might learn of many types of surges - including one that typically
    does damage.

    If numerical specs are useful, then a number defines power output
    when in battery backup mode. For example, this 120 volt UPS outputs
    two 200 volt square waves with a spike of up to 270 volts between
    those square waves. Is that conditioned power? Since they are
    selling products to layman whose eyes glaze over when the numbers
    appear, then those layman don't bother to learn how 'dirty' that UPS
    power is in battery backup mode. Those square waves are then called
    'modified sine wave'. Again, 'experts' using 'word association' would
    assume that is 'clean' electricity.

    A "modified sine wave" may be so 'dirty' as to even harm some small
    electric motors. But computers are far more robust. Computers
    already contain internal protection making that 200 volt square wave
    and 200+ volt spike irrelevant. A UPS that outputs such dirty power
    is also called 'computer grade UPS'. Color glossies let the naive
    assume that means 'clean' power. Sold by half truths and myths.

    Many types of UPSes exist. Ones that perform various 'power
    conditioning' include building wide systems located when power enters
    a building - including a dedicated earth ground. No wonder they cost
    $thousands. Where is that dedicated earthing wire on a plug-in UPS?
    Does not exist since it performs only one UPS function - protect from
    data loss.

    How cheap are those plug-in UPSes? Well a car battery used every
    day and exposed to all weather should last seven or nine years. Plug-
    in UPSes are made so cheaply that its battery typically dies in three
    years. Often costs more to replace a battery than to buy a new UPS.
    They are that cheap - have that few actual functions. Sold on
    numerous myths.

    For reliable service, consider a laptop that already contains a UPS
    and typically consumes less power. Need longer battery backup? Most
    laptops can also support a second battery.

    Do not chain batteries to a UPS. Risk from explosion and fire is
    created. Again, serious UPSes costs many $thousands for good reason.
    w_tom, Jun 27, 2007
  20. Well, ok, it makes AC electricity (from DC electricity ....)

    You know, when I make a cake I still need "ingredients". Just think of
    the battery as an ingredient for making AC electricity. If you are
    nice, I might share the recipie.
    Barry Watzman, Jun 28, 2007
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