Pure Sine Wave UPSes for New Dell PCs

Discussion in 'Dell' started by Daddy, Apr 8, 2010.

  1. Daddy

    someone Guest

    My XPS 420 has a 425 watt ps
    Using an APC Back-Ups RS 1500
    Under Power Chute Software it shows
    121 watts of the available 865 watts @ normal usage

    I live in an area with a flakey power grid
    Power loss during a storm is pretty common

    The computer works no different on battery.
    No noises or any odd behavior

    someone, Apr 10, 2010
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  2. Daddy

    Brian K Guest

    A question about UPS. Say it's rated as 500 watts (watts not VA).

    That means on battery it can run a 500 watt device for a period of time.

    But, does it mean you can't plug a 1000 watt device into the non battery
    side of the UPS? Or is that side of the UPS just like a power strip where
    you can plug in a 2000 watt heater?
    Brian K, Apr 11, 2010
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  3. Daddy

    Brian K Guest

    Thanks for that.

    I have my UPS set for 1 minute on battery before it shuts the computer down.
    Brian K, Apr 11, 2010
  4. Daddy

    Brian K Guest

    Not that I'd do this but for my information could you run a 1500 watt heater
    plugged into the battery side of a 500 watt UPS. I understand nice things
    wouldn't happen if there was a power failure but would the heater run while
    there was power?
    Brian K, Apr 11, 2010
  5. Daddy

    Al Dykes Guest

    This post is a flashback for me. Nearly 30 years ago I bought a UPS
    good for 80kVA for 30 minutes. Part of the acceptance test was
    simulating 80kVA of load with the biggest dummy load you've ever seen.
    Al Dykes, Apr 11, 2010
  6. Daddy

    Daddy Guest

    Very interesting discussion going on here. I wonder who started it all?
    Oh wait...that was me.

    I've made a few decisions in my quest for a UPS. Decision number one is
    that no way am I going to spend $400 for a (properly sized) sine wave
    UPS for my $800 computer. That's plain ridiculous. In the unlikely event
    that a power blackout kills my computer, I'll pay a little more and
    restore my backups to a perfectly good $500 computer.

    Decision number two is that I am not going to take apart any lawn mowers
    or other appliances to cobble together a proper UPS on the cheap. A
    person shouldn't need to become Rube Goldberg just to protect their

    Decision number three is that I am not going to pay any more attention
    to the half-truths and intentionally vague assurances provided by UPS

    Decision number four is that I'm going to let a few select people at
    Dell and APC know that its only a matter of time before Joe Consumer
    figures out what's going on.

    Finally, decision number five: I'm going to buy myself a properly sized
    stepped approximation UPS with the shortest transfer time I can find for
    as cheap as I can. In my area I'm not too worried about blackouts.

    Daddy, Apr 12, 2010
  7. Hi!
    When I was in the market for a new battery for one of my cheap-o APC
    plugstrip UPS units, I turned to eBay as there is no sense in paying
    $30 for a battery when that's what the UPS cost!

    The seller had an APC Smart-UPS 1500 for sale, listed as refurbished,
    that they asked (and received) $75 for. This UPS has true sine-wave
    output. (And in the case of the one sitting next to my desk, it was
    made in the US. Yes, I think that counts for something.)
    That's not what I said. :)

    I suggested that if you really did need a UPS with true sine wave
    output, that a lot of them could be found for *nothing* if you'll haul
    them away. That's because the batteries are invariably bad, and
    replacement batteries that carry the UPS manufacturer's seal of
    approval are (very) expen$ive.

    There's nothing cobbled together about it if you do it right. I only
    suggested it as a possibility in case the price of a new unit with a
    good battery was especially offputting, as it seemed to be.
    Be careful, there is a point where that number might devolve into what
    is technically (!!!) referred to as a "fib". If you find one that is
    leaps and bounds shorter than anything else you see advertised, it's
    reason to be suspicious.

    William R. Walsh, Apr 12, 2010
  8. Daddy

    Daddy Guest


    About the lawn mover...I was just making a joke.

    Daddy, Apr 12, 2010
  9. Daddy

    Daddy Guest

    I know you're all sitting on pins and needles over this...

    You may recall that I 'tested' my UPS to see if it could power my
    system, and the result of the test was that my system completely lost
    power. I have now discovered the reason why my system lost power: I am a

    (That's a 'dolt' for those unfamiliar with the lingo.)

    I performed the test by pressing the Off button on my UPS...which
    powered off the UPS. Duh! The correct thing to do was to pull the plug
    (of the UPS) out of the wall socket.

    Tonight I pulled the plug...and my system kept on working, without
    interruption. So there. No fancy, expensive, sine wave UPS for me.

    My UPS *is* somewhat under-powered for my system, by almost any
    calculation. I'll just wait for a good sale.

    Daddy, Apr 13, 2010
  10. Daddy

    WSZsr Guest


    You are a shlemiel.


    WSZsr, Apr 13, 2010
  11. Daddy

    Tom Lake Guest

    I though he was a schlimazel!

    Tom Lake
    Tom Lake, Apr 14, 2010
  12. Daddy

    Ben Myers Guest

    FWIW, Staples had a good solid decently rated APC UPS on sale a few
    weeks ago, and my son bought one to overcome the old and substandard
    electrical wiring where he lives. CDW had APCs on sale a few weeks ago,
    and I bought an APC Back-UPS 1250 for a little over 100 bucks. Made my
    life easier, because our local National Grid electric company has very
    frequent electrical hiccups, and my old UPS was worn out. I no longer
    suffer from spontaneous reboots. Of my computer. My brain still
    reboots regularly.

    Keep checking the sales, schlep on over to a sale, and buy a
    good-quality name brand UPS.

    How on earth a company like Dell can tell everyone that a UPS must
    provide A/C with a pure sine wave is beyond me. Or, to put it more
    succinctly, it is a large load of bullshit... Ben Myers
    Ben Myers, Apr 14, 2010
  13. Daddy

    Daddy Guest

    I'm not wild about UPSes by APC, because every APC unit I've ever owned
    - 4 in all - eventually starts to 'buzz' intermittently. Then I have to
    go underneath my desk and smack the thing once or twice to get the
    buzzing to stop.

    When I asked APC about this, they said "Oh, that's normal." I guess that
    makes my Tripp-Lite APC abnormal.

    Tom: A shlemiel spills coffee on a shlimazel. That's the difference.

    Daddy, Apr 14, 2010
  14. Daddy

    Daddy Guest

    In the interests of fairness and accuracy: Dell technical support will
    recommend that you buy a true sine wave UPS if you own a Studio XPS 8100
    or 9000 (and probably other models as well) if you ask them for a
    recommendation. However:

    1- Dell technical support reps don't always know what they're talking
    about; and

    2- The truth is.../any/ AC-powered electrical device prefers current
    with a sine waveform, but not all /require/ it. Certainly, critical
    electrical equipment, such as used in hospitals, should be protected
    with the more expensive sine wave UPS. Whether or not a PC with a power
    factor correcting power supply /needs/ a sine wave UPS is a question
    with too many variables. You have to try on your own and find out.

    The issue of expensive sine wave UPSes for PCs is a lot like the
    expensive supplements you hear about on radio informercials. Is there
    some evidence to back them up...yes...do you need to have them...no.

    Daddy, Apr 14, 2010
  15. Daddy

    JayB Guest

    you are joking? right?
    that so called buzzing is the self-test mode testing the battery and
    only lasts a short time. i guess about the time it takes for you to go
    below your desk and smack it.
    JayB, Apr 15, 2010
  16. Hi!
    Because that costs extra money...! (I do mean that seriously, as I
    doubt the majority of end-users are going to be cold-starting their
    UPS for a few minutes of computing.)

    It is a nice feature to have when you've got nothing else. I'll admit
    that I've turned on an old APC UPS on line power, took it off line
    power and used it to charge my cellular phone while on the go. What
    can I say? It worked and I couldn't find my car charger. I'm proud of
    this in a nerdy sort of way. :)

    Fortunately, it seems that most UPS units are now being made cold
    start capable. Even some of the cheap APC plugstrips can be used this

    William R. Walsh, Apr 15, 2010
  17. Daddy

    Tom Lake Guest

    Even though they can do it, it looks like APC still advises against it due to potential
    damage to components.

    Tom Lake
    Tom Lake, Apr 16, 2010
  18. Daddy

    Tom Lake Guest

    I was looking at an older manual, I guess. The current (no pun intended!)
    manuals don't seem to have this warning. All they say is that, "Cold start
    is not a normal condition"

    Tom L
    Tom Lake, Apr 16, 2010
  19. Hi!
    Ah, you'd better not. If the UPS was of a standby design (meaning that
    it only runs the load from its battery when the power is out or out of
    tolerance) you would be fine right up to the point where the power

    If you were lucky, the end result would just be a sudden shutdown with
    the UPS complaining about an overload. However, I'm inclined to think
    that the UPS will try to support the overload, maybe even do so for a
    little while and then go poof. At that point you'd smell the acrid
    odor of burnt silicon. (It's one of those few stenches that tells you
    in no uncertain terms that something has gone terribly, terribly wrong
    and may now be on fire.)

    A UPS that supports its load continually from the inverter (providing
    an additional layer of protection, as well as no switching delay)
    should also shut down when overloaded--but I suspect that it too will
    try and possibly go "boom".

    William R. Walsh, Apr 16, 2010
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