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Thread: Test your dry box

  1. #1
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    Default Test your dry box

    anybody have tried before testing the efficiency of their dry box??

    i tried before..........

    i place a small capfull of silica gel into the dry box, the meter reading state 30%
    the next day the gel turns pinkish.......
    what does this show?? there are moisture in the dry box??
    am i do the right test for my dry box???

  2. #2
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    Default Re: Test your dry box

    Where do you place your silica gel? near the door? near the meter? what do you want to test?

  3. #3
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    Default Re: Test your dry box

    i place quite near the door as where i place my lense.......test what? test the humidity in my dry box lor......hehehe

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    Default Re: Test your dry box

    A futile exercise if you ask me. There is humidity everywhere. How are you going to empirically test with silica gel the humidity in your dry box? Can you tell by the colour? "Oh, it is this shade of pink, therefore it is XX% humidity.


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    Default Re: Test your dry box

    Quote Originally Posted by Yatlapball View Post
    A futile exercise if you ask me. There is humidity everywhere. How are you going to empirically test with silica gel the humidity in your dry box? Can you tell by the colour? "Oh, it is this shade of pink, therefore it is XX% humidity.

    haha, just out of curiosity i just place the silica gel for a fun out of it......anyway when we get those off the rack dry box, our mercy is really at the hand of these glass cabinet......hope it will do its job well.......

  6. #6

    Default Re: Test your dry box

    of course, the desiccant turned pink coz it has absorbed the moisture.
    dry box should not be 0% humidity. else rubber parts will become brittle.
    45%-55% is ideal

  7. #7
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    Default Re: Test your dry box

    Why not just get an electric dry cabinet? And to put your mind at ease, further test its accuracy with a separate hygrometer.

  8. #8

    Default Re: Test your dry box

    Dude, if there were no moisture in the air, it wouldn't show 30% RH..

  9. #9
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    Default Re: Test your dry box

    Quote Originally Posted by ggodetucsamoht View Post
    anybody have tried before testing the efficiency of their dry box??

    i tried before..........

    i place a small capfull of silica gel into the dry box, the meter reading state 30%
    the next day the gel turns pinkish.......
    what does this show?? there are moisture in the dry box??
    am i do the right test for my dry box???
    Change silica gel to thirsty hippo. It absorb more.

    Regards,
    Arto.

  10. #10
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    Default Re: Test your dry box

    If I assume correctly, I believe that what you are trying to test is whether your dryer is working properly. To do so, open the cabinet and let the humidity drift a bit (perhaps open it for 1 minute). The humidity should rise in the cabinet. Next set the dial to the lowest setting and close the door. The cabinet should be able to dry the cabinet in about 30 minutes.

    If you place the silica gel near the door, do note that the door is seldom 100% air tight, so moisture do get into the cabinet. If you place the silica gel near your hygrometer, it will cause the hygrometer to register a false reading, as the region with the silica gel will be dryer. Furthermore, silica gel will absorb moisture as long as the humidity is more than 1%. So it is no wonder that your silica gel will turn pink.

  11. #11

    Default Re: Test your dry box

    Is there any way to test how accurate the hygrometer is?
    I know for a fact that even digital units are not always correct.

  12. #12
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    Default Re: Test your dry box

    Yes, it is possible. But there is actually little point in doing so. A simpler solution is to just put in another hygrometer, possibly digital, for second opinion.

  13. #13

    Default Re: Test your dry box

    I agree that a 2nd hygrometer is a better 'test' to be sure.

    My company has calibrated hygrometers by Spring Singapore and was told by my company rep that those calibrated hygrometers have a plus-minus 10% RH variation.

    I just bring mine to test against these units and know that they're fine and take note of the %RH difference for each hygrometer that I own.

  14. #14
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    Default Re: Test your dry box

    +/- 10% are norm for consumer.. actually already one of the better kinda. expensive humidity sensors (sensor alone) with +/-5% accuracy (@25degC)costs easily $200 and up.

    I think a lot of ppl are getting very paranoid over the settings of their dry cab and whether the dry cabs will do more harm to their equipment than without.

    Gone were days where everyone just dump their equipment into a cardboard box and dump sillica gel bags inside. I'm wonder if techonology is actually making us any.. smarter......
    “How fortunate for leaders that men do not think.” - Adolf Hitler

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    Default Re: Test your dry box

    In any case, you do not need to be very accurate with the humidity. As long as the humidity is within a specified range, it is very safe. If there are any occasional drifts,it will not have serious damage on the equipment.

    If your company has a professional cal lab, it may be ok to ask them to do calibration for you to ensure the accuracy. Otherwise, external agencies usually charge about a hundred dollars for the calibration, and it's really not worth the effort.

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  17. #17
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    Default Re: Test your dry box

    But the salts themselves are very expensive. There is no purpose in doing this unless its for professional reasons.

  18. #18

    Default Re: Test your dry box

    Just going a little off track... but something I picked up when I was an assistant to a photographer many moons ago....

    He looks at the dry cab and said to me... "you know... the rubber seals... how long you think they will last?" And I was stunned... I never really thought about it, but then again, looking at the old fridge in the house... I realised what he was driving at...

    So I asked him what is the best solution to getting the door to always "seal properly"...

    He answered : "grease". Some labs with glass bells uses grease to "complete the seal". Made sense to me. Just make sure you get the kind that does not erode the rubber.

  19. #19

    Default Re: Test your dry box

    In my lab, we use this vacuum grease and can be bought here.

  20. #20
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    Default Re: Test your dry box

    Quote Originally Posted by cantaresg View Post
    But the salts themselves are very expensive. There is no purpose in doing this unless its for professional reasons.
    I can't find the website doing calibration using normal sea salt . I hope the normal sea salt price don't burn our pocket .

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