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    Standby-UPS and External HDD

    Discussion in 'Accessories' started by wobble987, Sep 14, 2008.

  1. wobble987

    wobble987 Notebook Virtuoso

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    hi do anyone know the switching time from power line to battery of a standby-UPS (uninteruptible power supply) is fast enough to support an external HDD?

    ups model: http://catalog.belkin.com/IWCatProductPage.process?Product_Id=453571

    ====== if you care to read what i have found out======
    apparently the only info i could find is that the standby-UPS switching time is supported by a desktop PC because usually the power supply of a desktop pc has a feature (i think it was the PFC feature) to regulate power, so that it can withstand very brief period of power out (LESS than 100ms).

    not sure if the power adapter of an external drive have the same feature
    ===========================================

    anyone got any info/experience about Standby UPS and external HDD?

    thanks
     
    wobble987, Sep 14, 2008
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  2. Greg

    Greg Notebook Nobel Laureate

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    Well, last time I had an outage the switchover didn't cause a problem. But one does never know...
     
    Greg, Sep 14, 2008
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  3. wobble987

    wobble987 Notebook Virtuoso

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    you have a standby ups greg? is the external HDD on all the way throught the process? no interuption? were you accessing/writing to the external drive at the time?

    :)
     
    wobble987, Sep 14, 2008
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  4. metril

    metril Notebook Deity

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    The hard drive will be affected. The drive head writes by magnetizing the platter. The loss of current means loss of the magnetization, thus the head will not be able to write. The computer may see the drive as being on, but that 100ms switchover time will certainly cause missing bytes.
     
    metril, Sep 14, 2008
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  5. wobble987

    wobble987 Notebook Virtuoso

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    ah i found the manual and it said that the switchover time is 2-6ms. how much i can trust this im not sure. (if i trust) wikipedia said that it could be as long as 25ms.

    http://en.wikipedia.org/wiki/Uninterruptible_power_supply
    would the HDD notices? any opinion/experience?

    thanks
     
    wobble987, Sep 15, 2008
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