UPS for 27" iMac?

Discussion in 'iMac' started by EnterTheSwamp, Aug 15, 2010.

  1. EnterTheSwamp macrumors member

    Jun 29, 2010
    Do you guys use ups devices with your iMac? If so what size do you recommend for a 27" i7 iMac?
  2. Spike88 macrumors 6502a

    Jan 25, 2010
    I've always had great luck with our APC Backup UPS 1300VA device. I remember reading about a different person using the APC Backup UPS 1500VA device. With attached USB control cable, these size of UPS units work great.

    Remember that 27" sounds big (yes, physically big). But its also Energy Savings compliant. Meaning, its a low energy consumption device. Thus, IMO, the sizing between 1300-1500 VA box will do. I don't bother looking at Backup UPS units under 1200VAs.

    For best pricing, Future Shop often sells the 1300VA unit for "1/2 price" between Christmas and New Years. One of their 4 day madness sales. This is how I bought my APC unit for 1/2 price. :)

    Good luck.

  3. xraydoc macrumors demi-god


    Oct 9, 2005
    I always use a UPS with my desktop computers as well as for my NAS and Time Capsule devices, if for no other reason than to prevent disk corruption should the power go out during a disk write.

    I have a 1500VA unit by APC attached to my 27" iMac. With the USB cable attached, MacOS X will automatically power the machine off after a selectable amount of time on battery power, or when battery backup power level drops to a specified amount.

    I've got it set to power down when the battery gets to 45%. I figure this way it'll remain on for at least a few minutes in case it's a small power hiccup or brown-out. Anything longer and it'll then shut down gracefully.

    My ethernet switches Time Capsule and Drobo FS NAS are also running on (separate) smaller UPS units. They obviously aren't smart enough to turn themselves off, but since the Mac will have shut itself down long before their batteries have died, there will be no disk write commands going to them, so it'll be safe (or at least safer) when the power gets cut as the battery runs out.
  4. certsoft macrumors member


    Sep 29, 2007
    John Day, OR
    I had an old 600VA APC unit that ran my Mac Minis just fine. When I got the 27" iMac it choked. Got a Cyberpower CP1500AVRLCD and it works fine.
  5. EnterTheSwamp thread starter macrumors member

    Jun 29, 2010
    Can you use a server UPS with an iMac? Is there anything special about a ups intended for a server?
  6. fhall1 macrumors 68040


    Dec 18, 2007
    (Central) NY State of mind
    Nothing special about it except it probably costs more due to extended run time or better power conditioning. It'll be fine to use for your iMac.
  7. El Jobso macrumors newbie

    Apr 22, 2009
    Not to hi-jack the thread, but I have also just purchased a 27" iMac and looking into a UPS. I just ordered a CyberPower CP1500AVRLCD, and just read up that it may not transmit a pure sine wave (causing issues with the iMac's power supply). Can anyone shed some light on this situation, and whether I should return this UPS?
  8. Bryan Bowler macrumors 68040

    Sep 27, 2008
    I started a thread last night on this exact subject and would love to have more discussion there. I would provide a link right now, but I'm on the go and using my iPhone to post. Look for the thread on page 1 or 2 for more input...

    It's a very good question!

  9. certsoft macrumors member


    Sep 29, 2007
    John Day, OR
    As I said in post #4 I have that unit and it works fine. In addition to the iMac it's running 2 switches, a DSL modem, a MacMini server, and a firewall. I only ran it down to about 70% battery capacity left but had no problems.
  10. El Jobso macrumors newbie

    Apr 22, 2009
    When you're on battery power, is there any "buzz" noise emitting from the UPS? Also, how long have you had your iMac hooked up to the UPS? From all the posts I've searched through on various forums, the opinions seem to range from it doesn't harm the computer to complete destruction of PSU's.
  11. Thermonuclear macrumors 6502

    May 23, 2009
    First, you should know the power requirements of the 2010 iMacs:

    Maximum continuous power: 241W (21.5-inch models); 365W (27-inch models)

    Second, get a UPS that has a decent sinusoidal wave output. A cheap unit with a crummy square wave output will just add unnecessary work and heat to the iMac's power supply.

    Third, even the best UPS model isn't as good as is mains power. Have the iMac detect when a UPS is running in battery mode so that the computer may shut down gracefully as soon as possible.
  12. El Jobso macrumors newbie

    Apr 22, 2009
    The Cyberpower model I listed is theoretically capable of handling 900W, which would more than cover the 365+W demand of the 27" iMac. My main requirement is having some sort of battery backup for those odd occasions where the power drops or a brownout occurs.

    I suppose instead of the Cyberpower model, a refurbished APC SUA-1000 might be better due to its sine wave output.
  13. Spike88 macrumors 6502a

    Jan 25, 2010
    UPS "sizing" is always a tricky question. Even for the experienced. Size depends on direct connected devices, one's expected future growth, one's minimum "run" time and one's maximum "run" time.

    For Backup UPS "sizing", may I suggest running the APC Sizing URL. At end of their selections / questions, it recommends a "good, better, best" product size. For example, 900VA, 1200VA or 1300VA unit. For me, I don't pick the bottom and I often don't pick the top. Most of the time, I pick the middle "size". With that "VA" size chart in hand, I then decide to purchase APC product or perhaps a different brand product (of same size). To me, knowing the "sizes" is the first question answer.

    For APC Backup UPS, sizing (for your own system setup), surf:
    See their "PC or Workstation" column.
    Select "Configure now" button.
    If your exact iMac device is NOT listed, pick simular "power need" device. For example, Desktop with 30" monitor with Intel i7 processor.
    Continue to select your other unique items.
    Select "show UPS solution".

    For my selection choices, it recommended:
    Good: APC BACK-UPS 900VA 120V
    Better: APC BACK-UPS RS 1300VA LCD 120V
    Best: APC Smart-UPS 1500VA LCD 120V

    For me, I bought "APC BACK-UPS RS 1300VA LCD 120V" unit. It's been working great for the last 7 months...

    Good luck...

  14. DarthMoops macrumors regular

    Aug 7, 2010
    Baltimore MD
    What fhall1 said.

    Just be sure the socket the server level UPS requires is compatible with your house. ie not L5-15 or L6-30, you want NEMA L5-15
  15. El Jobso macrumors newbie

    Apr 22, 2009
    That same model also has a "Stepped approximation to a sinewave" for output according to APC's website. I assume if you've been having no issues with a non-"Pure Sine" signal for 7-months, then the Cyberpower should theoretically work as well.
  16. marvS macrumors newbie

    Jan 26, 2008
    APC Back-UPS BX1300G

    I just picked one of these units and plan on connecting it to my 24" Intel iMac and Airport Extreme. I thought about the pure sine wave vs stepped sine wave issue and here's my two cents.
    When I go camping I use a pure sine wave inverter to power my electronics. The reason is I am POWERING the devices from the battery for a relatively long period of time. In the case of a UPS my goal is only to be able to do a graceful shutdown and wait for line power to be restored. So if the iMac can handle the stepped sine wave for the time necessary to do that then I'm fine. Should it compromise the iMac power supply in any way, I'm going to rely on AppleCare to take care of it. I think placing the iMac on a UPS in the first place, demonstrates a desire to protect my investment over just using a cheap surge suppressor or nothing at all! In addition APC and some other companies offer product insurance. Come to think of it, the computer may be covered by my homeowners insurance, I'll have to ask my agent.
    Anyway that's what I think.
  17. thaniel98 macrumors newbie

    Jan 30, 2008
    The server grade UPS will give you a pure sinewave output and has a heavier transformer for voltage regulation. The consumer grade will have a step-approximated sinewave on the output.

    I have tested both with the 27in iMac with no difference in performance.
  18. LPZ macrumors 65816

    Jul 11, 2006
    I prefer FedEx myself. :rolleyes:

    Sorry, couldn't resist.
  19. EnterTheSwamp thread starter macrumors member

    Jun 29, 2010
    Are there adapters that you can buy to convert these? Say a UPS with a L5-30p cord?
  20. Sun Baked macrumors G5

    Sun Baked

    May 19, 2002
    If you are worried about the cost, just buy a reconditioned APC Smart UPS 1400/1500 or their rebranded IBM UPS twins.

    About $200-250 for reconditioned plus shipping, and come with new batteries and a warranty.
  21. thaniel98 macrumors newbie

    Jan 30, 2008
    You can always change the plug on the UPS but keep in mind that if you get a UPS that is originally a 30 amp plug (L5-30P) and replace it with a standard wall outlet 5-15P that is 15 amps you will be downgrading the UPS. A 30 amp UPS will be in the 3000VA range where as the 15 amp UPS is in the 1500VA range.

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