On the waterproof-ness of Banglejs 1

Hi everyone! first post on the forum here.

First of all congratulations to everyone contributing to the Banglejs device and ecosystem, I think it is a great device and I had fun using it. Looking forward to contribute more meaningfully to the project.

The theme of this post however is the waterproofness of Banglejs1. Yesterday I decided to test it and go for a swim in a river. It stopped working after a couple of minutes and I could see some water in the display. I am now leaving the banglejs to dry in the sun, but it is still completely dead.

From my understanding the banglejs1 should be waterproof up to 10m underwater, but I swam only on the surface. Does that mean that my banglejs was defective?

Cheers

Hi.

My understanding of IP67 and IP68 is "don't put them underwater or under a water stream". The first number means dust insertion protected and the second number the same for water. IP67 is water resistant for accidental static submersion up to 1m (0.1 ATM) for 30min, while for IP68 it depends on what the manufacturer has tested. As I understand static means not underwater streams like swimming or under the tap and accidental means "don't do it on purpose". Both standards should protect against rain or splashes for a few minutes. In any case, all of this is tested with the device new and without any previous shock or wear.

For example, the Samsung Gear S3 is IP68 and the company says: "under specific conditions, the Gear S3 can withstand accidental submersion up to 1.5 meters underwater for 30 minutes [...] IP ratings are not indicative of a device’s ability to be used during aquatic activities such as swimming. This is where ATM ratings come in". My conclusion is: direct splashes of light rain probably OK, anything else don't do it.

I would trust more a 1ATM device than an IP68 one, but I would prefer 3ATM for showering and 5ATM for swimming.

https://news.samsung.com/global/can-you-­swim-with-your-wearable-these-water-resi­stance-ratings-will-help-you-find-out

Thanks for the detailed and informative reply.

If that's the case I think the page https://www.espruino.com/Bangle.js#featu­res should be modified, as it claims the following:

IP68 Waterproof: up to 10m underwater

while that would be the result of an ATM1 device.

In any case this claim is misleading in my opinion, as it can easily be interpreted as "if it can go 10m underwater, for sure I can swim with it", unless someone is knowledgeable of waterproof standards.

IP68 Waterproof: up to 10m underwater

It seems to me very likely that it has been tested for IP68 up to 10m. I agree that IP68 ratings are totally misleading, a lot of people will understand that it's suitable for swimming. This isn't new, in the 80's and 90's Casio days 1ATM watches would support 10m of water pressure but they were not recommended for swimming or diving. Take in mind also that IP68 doesn't imply that it has been successfully tested for IP65, IP66 or IP66K (water jets). If a device supports water jest it should specify it with a slash notation (like IP65/IP68, IP66/IP68 or IP66K/IP68). Any mint IP68 device should support light rain or splashes. No IP67 or IP68 device from any manufacturer should be used for shower or any water activity, unless specified otherwise.

https://en.wikipedia.org/wiki/IP_code

This is just my understanding of IP ratings, not any position of Espruino in this matter. My self, I don't use the BangleJS 2 for shower or swimming and I try to cover the watch under the sleeve with heavy rain. In my wishlist for a possible future BangleJS 3 is water resistance for swimming https://forum.espruino.com/conversations­/374260/?offset=125#16992573 (read also Gordon's reply to my comment).

Now that, under pressure, some water has entered, without opening it is very unlike that all the water will come out.

It would be ideal if the features page would clarify about this, something like "Accidentally only, do not submerge on purpose. Not suitable for water jets like shower or swimming". In the end, this is what IP68 means, but who reads the standards while searching for a watch?

Take in mind also that IP68 doesn't imply that it has been successfully tested for IP65, IP66 or IP66K (water jets)

Good to know, I had automatically assumed the opposite.

My self, I don't use the BangleJS 2 for shower or swimming and I try to cover the watch under the sleeve with heavy rain.

I think this is what I am going to do as well with the new banglejs2 I will buy.
Or with the banglejs1 if it recovers in the next days.

Now that, under pressure, some water has entered, without opening it is very unlike that all the water will come out.

As of now I removed the back cover, removed as much water as I could (there was A LOT in it) and let it open to dry. Will update in the next days on whether it comes back to life or it can be considered a sacrifice in the name of waterproofing standards :)

It would be ideal if the features page would clarify about this, something like "Accidentally only, do not submerge on purpose. Not suitable for water jets like shower or swimming". In the end, this is what IP68 means, but who reads the standards while searching for a watch?

I created a PR to modify the website (https://github.com/espruino/EspruinoDocs­/pull/701) and add the same disclaimer that the banglejs2 has.

Hi, sorry to hear this - and sorry for the delay, I was off last week. I've now merged that PR.

The IP ratings are really misleading, and I should really have removed the Bangle.js 1 references at the same time as the 1, but we were selling Bangle.js 2 then so I didn't think to do it.

As others have mentioned, in theory the Bangle.js 1 should be able to do static 10M of water as the case is sealed and there are o-rings and oil on every button, but when swimming especially if it's on your arm, you're ramming water right past it repeatedly, and potentially putting a lot more pressure on it at times. Pressing the buttons can also be an issue and I don't believe is part of the test.

Have you had any luck with the Bangle.js 1? At least if it was river water it won't be saltwater so there is some chance the Bangle may be ok when fully dry, even if you have to rinse the PCB with clean water again.

Hi, sorry to hear this - and sorry for the delay, I was off last week. I've now merged that PR.

No worries.

At least if it was river water it won't be saltwater so there is some chance the Bangle may be ok when fully dry, even if you have to rinse the PCB with clean water again.

Yes it was river water. I have to admit that now that I understand how the waterproofing standards work, I realize that I have put my bangle under a quite harsh test. I used it while kayaking on a river and everything went fine, even though it got hit with a ton of water splashes and I even dipped it under the water several times while on the move. That did not cause any visible malfunction of the watch, and I did not see any water under the screen.

Once I stopped kayaking I went for a very short swim (~ 5 mins) and it broke :D

Today after leaving it for several days disassembled to dry, I re-assembled it and plug it under charge. At first it was working fine, but after some time (~30 mins) it shut down again, and now even if I put it under charge it does not give any sign of life. Any idea on what could have gone wrong?

even if you have to rinse the PCB with clean water again.

I did not rinse it with clean water, do you think that could help? If so, how?

Additionally when re-assembling the bangle, I found very hard to put back the rubber waterproofing ring in the correct position. It seems to me that its diameter is a couple of millimeters short of what the bangle would need. Could it be a defect or is it expected?

I did not rinse it with clean water, do you think that could help? If so, how?

I would definitely give that a go. What can happen is even when dry, stuff gets deposited on the PCB or between the connections on the chip and that can be conductive enough that it connects the pins together and causes problems. Or worse, if it's wet and there is electricity the wires can get electrolytic corrosion and then there really isn't much you can do.

After giving the PCB a rinse (try not to get the battery wet if you can), leave it to dry somewhere warm (and try as hard as you can to make sure it is dry) and maybe it'll come back to life again properly.

I found very hard to put back the rubber waterproofing ring in the correct position. It seems to me that its diameter is a couple of millimeters short of what the bangle would need

It is possible it has contracted slightly over time. However when closed it should have made a good seal. I have seen Bangles where the rubber ring wasn't in place, but in that case you should have noticed that the rubber had been crushed in some places.

After giving the PCB a rinse (try not to get the battery wet if you can), leave it to dry somewhere warm (and try as hard as you can to make sure it is dry) and maybe it'll come back to life again properly.

I will give that a try and update.

I have seen Bangles where the rubber ring wasn't in place, but in that case you should have noticed that the rubber had been crushed in some places.

That's actually what I noticed, there is a small part of the ring where there is a sort of "cut" (the ring is not separated in two pieces though). I don't really know how to explain, but there is a sign of "crushing" on it. I will post a picture once I disassemble it again to rinse it.

I will give that a try and update.

You should use distilled or deionized water like the water used for clothing ironing.

there is a sign of "crushing" on it

Argh, sorry about that - that could well have been it then. The problem's been that it was a very difficult thing for us to test here without disassembling every one of them that we receive :(

You should use distilled or deionized water like the water used for clothing ironing.

Thanks for posting that, otherwise I would have used normal water like a dumbass ahah

So here is the update, I rinsed the pcb with de-mineralized water, but I did not try to switch on the banglejs1 yet. I noticed there is some "greyness" on the pcb around some components (R7,C4,R6). Is that a sign that some residue from the river water is still there? Should I use something more abrasive to try to remove it?

I attached pictures of the pcb and of the crushed rubber ring.

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Hmm - that greyness does look like a bit of corrosion - maybe try going over it with a toothbrush?

However that black PCB is the heart rate sensor - it's not very important. The one you'll really care about is what happens if you peel up the button PCB and 'unwrap' that whole black flex PCB, then try and get the PCB+LCD out from the black plastic 'puck'. On the back of the LCD there's the main processor PCB and that's the one that it'll be important to try and get clean.

Sorry to see the seal though - that looks particularly odd. The odd time I've seen them pinched they were flattened, but that one looks like something sharp has almost cut through it and I'm not sure how that could really have happened!

Ok, after actually cleaning the right pcb and scrubbing all the corrosion away with a toothbrush, my banglejs1 is back alive!! :D

Thanks @adjtm and @Gordon, you have been both very helpful to get this fixed!

However I think the battery is kinda messed up. It lasted about 8hrs on idle after a full charge, and the battery widget always showed as if there was no battery (except for the few minutes after charge). Is it possible to change it?

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Great! Glad it's working again!

It is possible to replace the battery - and I'd have to check but I think we may have a few replacements in stock still.

However the short battery life might not be the battery, but some slight short in the circuitry causing a high power draw - I guess you could try charging the battery up and see if you can measure the voltage across it when it's charged? If it's getting 4.2v when charged but the watch is still reading low then it's likely that increased resistance on the board is what's making it read the voltage as very low.

I guess it's also possible that the resistance has meant that something that draws a bunch of power (like the GPS) is turned on? 8 hours of life is about what you'd expect if that's what it is.

I do not have the tools to measure the battery voltage at the moment, however yes, the 8hrs battery life where with GPS on.

A full charge without GPS on lasted <24hrs. So I think there is still some issue, but it is fine :) If I ever get my hands on a multimeter, I will try to measure the voltage.