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  1. #1
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    Question vacuum confusion



    hello all
    not only new to this site but fairly new to refrigeration. I took the plunge and bought myself some cheap and nasty digital gauges with a built in vacuum gauge. When using the gauge it reads 0 for atmospheric and reduces as the vacuum draws to -762 microns or -1013 millibar. to me this does not corelate. Is it me, can perhaps one of you gents enlighten me. Surley those microns should be torr?



  2. #2
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    Re: vacuum confusion

    Its just different units of measurement, if I could work out how to post files I would include a conversion chart, I use an analogue Torr gauge as I prefer them to the electronic type.

    Cheers
    Tutto il Mondo e un Paese

  3. #3
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    Re: vacuum confusion

    Hi, fusbblood

    Quote Originally Posted by fusbblood View Post
    hello all
    not only new to this site but fairly new to refrigeration. I took the plunge and bought myself some cheap and nasty digital gauges with a built in vacuum gauge. When using the gauge it reads 0 for atmospheric and reduces as the vacuum draws to -762 microns or -1013 millibar. to me this does not corelate. Is it me, can perhaps one of you gents enlighten me. Surley those microns should be torr?
    welcome to RE forums,

    please search forums for "vacuum", "vacuum units" ... and similar words, for sure you will find some good explanation..

    or follow those links to find more links within posts

    http://www.refrigeration-engineer.co...t=vacuum+units

    http://www.refrigeration-engineer.co...t=vacuum+units

    of course if you try harder you will find more info on RE forums.... good luck ...

    Best regards, Josip
    Last edited by Josip; 10-04-2010 at 06:34 PM. Reason: spelling

    It's impossible to make anything foolproof because fools are so ingenious...

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    Please, don't teach me how to be stupid....
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  4. #4
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    Re: vacuum confusion

    That must be Refco Digimon!
    Give it to your kids as new funny toy.
    Last edited by nike123; 11-04-2010 at 02:31 AM.

  5. #5
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    Re: vacuum confusion

    Quote Originally Posted by El Padre View Post
    I use an analogue Torr gauge as I prefer them to the electronic type.

    Cheers
    What analog torr gauge could clearly read 0,5 torr?

  6. #6
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    Re: vacuum confusion

    In the US we use microns. typically I pull down to 400 microns if this gives you a point of reference.

  7. #7
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    Re: vacuum confusion

    the original confusion is was the reading of -1013 millibar and -762 micron as being the same pressure reading

    I have four kids the youngest is 23
    I wouldnt trust him with a new toy /

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    Re: vacuum confusion

    Quote Originally Posted by fusbblood View Post
    the original confusion is was the reading of -1013 millibar and -762 micron as being the same pressure reading

    I have four kids the youngest is 23
    I wouldnt trust him with a new toy /
    You mean -762 Torr?

    1013 mbar is 759,81 Torr!
    Last edited by nike123; 25-04-2010 at 08:45 PM.

  9. #9
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    Re: vacuum confusion

    thats what I thought but litterature and decal on gauge says micron!
    Back on ebay me thinks!!

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    Re: vacuum confusion

    Than search for Digicool!
    And buy vacuum gauge separately.

  11. #11
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    Re: vacuum confusion

    just found how to add a signature
    and the edit button

    off to do some work now on nights
    Last edited by fusbblood; 26-04-2010 at 01:06 AM.
    It is better to ask a silly question and look stupid for a few minutes than not ask a silly question and remain stupid forever.

  12. #12
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    Re: vacuum confusion

    762 microns is 1,01592mbar
    prefix - is probably there to indicate pressure below atmosphere!
    But then again -1013 mbar mean that vacuum is down to 0,25 mbar absolute or 187,52 microns.
    So, it remain unclear which is it, 762 microns or 187,52 microns.

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