Author Topic: moisture and electronics  (Read 7280 times)

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Offline micksmelanieTopic starter

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moisture and electronics
« on: June 28, 2020, 04:59:32 pm »
If I have electronics stored in an anti-static zip bag and this bag inside a shoe box has any way to escape the accumulation of moisture inside the box and inside the bag?
the anti-static zip bag I left open for better air circulation
« Last Edit: June 28, 2020, 05:02:01 pm by micksmelanie »
 

Offline bob91343

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Re: moisture and electronics
« Reply #1 on: June 28, 2020, 05:12:59 pm »
If you leave the bag open, of course moisture can accumulate.  If you seal the bag, make sure first that you do it in a dry environment else you will trap moisture.

That's why silica gel is used, to absorb moisture that can corrode electronics.
 

Offline jogri

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Re: moisture and electronics
« Reply #2 on: June 28, 2020, 05:24:31 pm »
If you are paranoid about the level of moisture you could put your electronics inside a sealed bag, together with a moisture indicator like cobalt chloride paper and freshly baked silica gel (just leave it in the oven @150°C for a few hours).

Btw, why would those components need air circulation? Just close the bag (or use a ziplock bag) and you are good to go (as long as you don't store it in your shower).
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #3 on: June 28, 2020, 05:51:24 pm »
I put 3 sachets of silica gel inside the box but I did not put 1 sachet of silica inside the antistatic zip bag because there is not enough space for the sachet so the bag stays open outside the bag is the box with the 3 sachets of silica


electronics inside that open bag zip antiestatic and that bag inside the shoe box and inside the box has 3 silica gel sachets protects from moisture?
« Last Edit: June 28, 2020, 05:53:39 pm by micksmelanie »
 

Offline jogri

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Re: moisture and electronics
« Reply #4 on: June 28, 2020, 06:05:18 pm »
Silica gel bags only work in (nearly) airtight containers... Get yourself a big ziplock bag, put your antistatic bag AND the silica gel in and then close it. Btw, silica gel is absolutely useless after 3-4 days in open air so you have to heat those bags for a few hours if you want to use them (i don't know if the paper packaging of the silica gel can handle the heat so you have to get creative).
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #5 on: June 28, 2020, 06:15:08 pm »

I used a ziplock bag some time ago with 3 sachets of blue silica gel inside the zip and I realized that moisture was entering because the sachets saturated they turned pink and after that I was suspicious of the ziplock bags because if they let the moisture in and the sachets saturate the moisture gets stuck inside the zip is worse for the electronics if I put the 3 sachets inside the shoe box will it not look like airtight? without silica gel, no store tip prevents moisture accumulation?
 

Offline bob91343

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Re: moisture and electronics
« Reply #6 on: June 28, 2020, 07:20:54 pm »
Closing the box makes no difference.  The box must be airtight.  Sealed.

The contents must be shielded from moisture entering via air pressure (water vapor) and the silica gel inside the enclosure will absorb the little moisture that is left.  Any leaks and all your efforts are wasted.
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #7 on: June 28, 2020, 09:04:47 pm »
I will buy new ziplock bags at Alixpress and I will also buy new silica gel sachets but before that what is your recommendation for me to store these electronics with the minimum possible risk of moisture going to the electronics? today I put them in a common bag and anti-static bag with zip (bag with hole) the bags I leave them open (air exchange) and I put these bags inside a closed shoe box inside the box has 3 sachets of 2g of silica gel


I will wait 2 months to receive the package
 

Offline David Hess

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Re: moisture and electronics
« Reply #8 on: June 28, 2020, 09:51:54 pm »
I used a ziplock bag some time ago with 3 sachets of blue silica gel inside the zip and I realized that moisture was entering because the sachets saturated they turned pink and after that I was suspicious of the ziplock bags because if they let the moisture in and the sachets saturate the moisture gets stuck inside the zip is worse for the electronics if I put the 3 sachets inside the shoe box will it not look like airtight? without silica gel, no store tip prevents moisture accumulation?

Common polyethylene bags are pretty permeable.  Try metalized Mylar or polyester bags which are gas tight which is why they are used for foods which would be affected by oxygen and water vapor.

The above is why naphthalene moth balls cannot be packaged inside polyethylene; it just lets the naphthalene diffuse out.
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #9 on: June 28, 2020, 10:04:03 pm »
I bought this ziplock bag but it will only arrive in two months so I want to preserve this electronic part that I mentioned as storing it
https://pt.aliexpress.com/item/32926129492.html?spm=a2g0s.12269583.0.0.1d8e26dfAUM6I0


this bag is good and waterproof?
« Last Edit: June 28, 2020, 10:18:31 pm by micksmelanie »
 

Offline Halcyon

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Re: moisture and electronics
« Reply #10 on: June 28, 2020, 10:31:38 pm »
Waterproof is one thing. Water vapour/moisture proof is entirely different.
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #11 on: June 28, 2020, 10:35:44 pm »

I want to protect electronics from moisture that causes corrosion, and I want an opinion on this ziplock from aliexpress link above
 

Offline helius

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Re: moisture and electronics
« Reply #12 on: June 28, 2020, 10:39:57 pm »
Common polyethylene bags are pretty permeable.  Try metalized Mylar or polyester bags which are gas tight which is why they are used for foods which would be affected by oxygen and water vapor.

The polyester bags are normally sold as "freezer bags" in the grocery store. They will do an adequate job blocking moisture ingress if fully sealed.
I am a little skeptical about the idea that silica gel is useless after 3 days in air. If you want to fully absorb all moisture leaving the contents of the bag totally dry, that's one thing. But the usual concern is not moisture, it's condensation. During daily temperature cycles, the dew point changes leading to a cycle of H2O in liquid and vapor phases (like in a terrarium). Silica gel can absorb enough moisture to stabilize the humidity and prevent outright condensation.
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #13 on: June 28, 2020, 10:48:54 pm »
I will repeat as I am storing my electronics, it is inside an anti-static zip bag with some holes the bag is open to the moisture not stuck and the bag is inside a closed shoe box inside the box I also put 3 sachets of 2g of silica gel how many days will these 3 silica gel sachets protect everything inside the box?

When you don’t have silica, zip bags etc. do you have a day to protect against moisture and prevent condensation?

this is PE Zip lock bag from aliexpress link good or bad? two months for him to come to my house
 

Offline Halcyon

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Re: moisture and electronics
« Reply #14 on: June 28, 2020, 11:12:07 pm »
I will repeat as I am storing my electronics, it is inside an anti-static zip bag with some holes the bag is open to the moisture not stuck and the bag is inside a closed shoe box inside the box I also put 3 sachets of 2g of silica gel how many days will these 3 silica gel sachets protect everything inside the box?

There is no easy answer. It depends how fast the silca gel absorbs moisture and how much moisture is in the air.

I don't live in a particularly humid environment but I found even the 40g units I have are saturated within a few days (initially at least). I used to use these "reusable" silica gel packs in aluminium cans for storing camera lenses in Pelican cases. Once saturated, you can "reactivate" them by baking them in a 150 degree C oven for a few hours.
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #15 on: June 28, 2020, 11:13:54 pm »
When you don’t have silica, zip bags etc. do you have a day to protect against moisture and prevent condensation?

this is PE Zip lock bag from aliexpress link good or bad? two months for him to come to my house

 

Offline David Hess

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Re: moisture and electronics
« Reply #16 on: June 28, 2020, 11:18:44 pm »
The polyester bags are normally sold as "freezer bags" in the grocery store. They will do an adequate job blocking moisture ingress if fully sealed.

The freezer bags I have seen were all just thicker polyethylene.

Do a search for "Mylar metalized zip lock" and you will find lots of suitable bags.
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #17 on: June 28, 2020, 11:25:22 pm »
Mylar metalized zip lock are very expensive I would like to purchase many units but it is unviable I would have to cancel the purchase of the PE Zip lock bag 0.12mm from Aliexpress

When you don’t have silica, zip bags etc. do you have a day to protect against moisture and prevent condensation?
 

Offline jogri

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Re: moisture and electronics
« Reply #18 on: June 29, 2020, 08:26:50 am »
I am a little skeptical about the idea that silica gel is useless after 3 days in air. If you want to fully absorb all moisture leaving the contents of the bag totally dry, that's one thing. But the usual concern is not moisture, it's condensation. During daily temperature cycles, the dew point changes leading to a cycle of H2O in liquid and vapor phases (like in a terrarium). Silica gel can absorb enough moisture to stabilize the humidity and prevent outright condensation.


I use desiccants for my work all the time (i need ppm levels of moisture for some stuff) and even good quality silica gel with an indicator gets discolored after a few days in open air, so crappy chinese stuff will probably last a bit longer (as it is just not that good ad adsorbing moisture) but i won't give it more than a week (and you need a lot of it, i usually use ~20g per litre of air). There are much better desiccants than silica gel available (namely phosporous pentoxide), but they are more difficult to handle (the pentoxide gets converted to liquid, highly concentrated acid) and silica is absolutely fine for most jobs.

@micksmelanie: You don't need an absolutely airtight container for your parts, so good quality ziplocks (or jam jars) are fine. If you however want to have a container that is guaranteed to be absolutely airtight you might want to look at Schott laboratory glass bottles, but that will set you back 50 bucks for a 1l flask.
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #19 on: June 29, 2020, 09:45:10 am »
Inside the shoe box I put 3 sachets of 2g silica gel but it’s not airtight and I don’t know how many days the silica will resist. I put the 3 sachets last Wednesday

Help me find the best method of storage and protection from moisture condensation when there is no ziplock and no silica gel

I saved the video game cartridge inside the antistatic bag and left the bag open because there is no space to put silica inside and this antistatic bag I put inside a closed shoe box with 3 silica sachets inside the box
 

Offline jogri

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Re: moisture and electronics
« Reply #20 on: June 29, 2020, 11:59:18 am »
If you are looking for cheap, (semi-) airtight containers you might want to look at tupperware/icecream boxes. You don't need a fancy high end solution, your parts wont cease to function if they are exposed to a little bit of humidity. As long as you don't pack the components while you're showering you will be fine.

If you don't want to use silica gel (or any other desiccant) you have to get rid of the moisture that is still inside the container. A good way to do this would be to heat the container to 75 °C for 6-12h before you put anything in (although that is really not necessary for your use). Btw, if your container is airtight you only need the silica to get rid of the initial moisture, so you only need a small amount (a few grams).

(The absolute best solution would be to put your electronics inside a Schott laboratory glass bottle while everything is inside a glovebox that actively removes moisture, that way you can store it for years at sub-ppm levels of humidity. Is this a practical solution? Absolutely not.)
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #21 on: June 29, 2020, 12:05:33 pm »
I store my video game cartridge inside an open anti-static bag, this open anti-static bag is inside a closed shoe box and inside that box I put 3 silica gel sachets inside the box and will the bag condense moisture and damage the cartridge? what can i improve for two months i receive in my home silica gel and ziplock bag?
 

Offline micksmelanieTopic starter

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Re: moisture and electronics
« Reply #22 on: June 29, 2020, 06:51:38 pm »
up
 

Offline SparkyFX

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Re: moisture and electronics
« Reply #23 on: June 29, 2020, 08:45:12 pm »
what can i improve for two months i receive in my home silica gel and ziplock bag?
Condensation happens when temperature (or pressure) differences lead to air being unable to "hold" moisture (hot/humid air becomes cold/dry air, so most of the moisture will condensate at the coldest area). So it depends where that box is, which temperature swings the container will be subject to and which temperature your parts have if you want to avoid them actually getting wet and corrode. It might be better to store them pretty much open inside a home, as the construction and wood furniture itself buffers humidity to some extent, while the anti static bag buffers nothing. If the building wouldn't, it would become moldy pretty quick.

Some desiccants do not only saturate and are useless afterwards, they might as well buffer the humidity and extend the range before condensation will visibly happen depending on the amount of air (and therefore absolute humidity). Ofc they are more capable to do so when dry.
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Online tggzzz

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Re: moisture and electronics
« Reply #24 on: June 29, 2020, 09:56:07 pm »
If you leave the bag open, of course moisture can accumulate.  If you seal the bag, make sure first that you do it in a dry environment else you will trap moisture.

That's why silica gel is used, to absorb moisture that can corrode electronics.

Not quite. You need to think about relative humidity.

If the bag is sealed, the number of water molecules remains constant. Whether they are in solid, liquid or gaseous form depends on the temperature. The temperature at which they condense into liquid depends on the relative humidity and temperature when the bag was sealed.
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