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Compaq R3000h UPS

Discussion in 'Alternative Energy' started by bbhs, Mar 31, 2009.

  1. bbhs

    bbhs New Member

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    Anybody familiar with the R3000h ups I believe it is a re-badged APC unit with a reasonable output and management software.
    I have a couple of these which I was looking to see if it would be possible to strip down and add GTI circuitry to it possibly where the battery bank would have been.
    The bulk of the construction already having been done i.e the main inverter - if it would be possible this would make a nice rackmount unit suitable for small wind turbines.
    They can be picked up fairly cheaply I bought 2 for 40GBP - there is also USA and UK variants so could be a good project for all of us as an alternative to the fully blown GTI project.
    Spec link - ACX Recycling - R3000h Compaq R3000h 242705-002
     
    Last edited: Mar 31, 2009
  2. tcmtech

    tcmtech Well-Known Member Most Helpful Member

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    I have been playing with modifying UPS circuits to do exactly what you are trying to do.
    I am coming to the conclusion that with a few circuit modifications the basic H-bridge can be used along with the main power transformer without any problems except the heatsinks are not big enough on the ones I have been looking at. They run hot after a few minutes! :(
    But unfortunatly the power transformers are often 15 minute duty cycle rated at full output on almost everyone I have taken apart that uses a fixed size or internal battery.
    The actual power transformer continuous VA ratings are more like 1/3 or 1/2 the maximum rating. :(
    This does give them an excellent overload capacity though. But do to the limited run time design I think thats where part of the heatsink problem comes from as well. ;)

    I do have a large Sola 2500 VA rated unit that ran off an external battery pack that does have a full 2500 VA continuous duty rated tranformer and big fan cooled heat sinks. But it is the only one like that I have found so far. However, it also ran off a 60 volt battery system so the transformer will only work with a system voltage of 60 volts or higher.

    If there was a way to get into the actual program software that the UPS control systems run on I think it could very well be possible to reprogram them for full GTI operation with only a few added circuit components and minor modifications.
    I know they already have most of the feedback and monitoring components on the boards, Its just a matter of finding out how to rework or modify them to serve a slightly different purpose. :)

    But that is only a theory it may very well not even be possible. I just dont know.

    By design they are about 90% of the way to being GTI capable. ;)

    What I have found as far as physical modification to the power side is they need the reverse blocking diode on DC the input, the correct size H-bridge filter capacitor, Larger heat sinks, and a correct size power factor correction capacitor on the output. :)

    The rest is just a matter of a control system retrofit or possible program rework, In thoery.

    If any one has any ideas or knows how to hack the programs on the better UPS units please post it! :)
     
  3. bbhs

    bbhs New Member

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    Thanks for the reply tcmtech - yes these are 3000va and very heavy construction also were a few thousand dollars when new.
    I do not think they run as high as 60V input but will be stripping one down maybe over the weekend and will check on the battery input.
    I did use these on a bank of servers and they would run for about 40 mins - not to sure on the actual load - should have measured it :-(
    If anybody else is familiar with this model any info would be appreciated as I am sure they would make a great GTI unit after a suitable sized H-bridge etc as suggested.
     
  4. dave

    Dave New Member

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  5. tcmtech

    tcmtech Well-Known Member Most Helpful Member

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    Heres an actual specs write up. You may be a bit disapointed!

    Battery Pack I found listed for it uses 16 X 6volt 12Ah = 96 volts!

    Bummer! All the way around! Bummer! :(
     
  6. bbhs

    bbhs New Member

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    Thanks for the info - Yeah what a bummer :(
    Mine are the older type and are the 3U units and hopefully will have transformers - will get to have a look over the weekend and let you know.
    Thanks for your input.
     

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