Bangle.js charger hot and plug melted, how to get a spare.

[espruino-discuss2]

Posted at 2020-04-03 by PeterS

My charger cord just got very hot and the connector pins are now melted in the plastic, dont come out with spring any more. Don't know how this happened, maybe shorted out when shifted when charging. I hope it stops charging when this happens. Still works, but only in one position with sticky tape. How can i get a spare one?

[espruino-discuss2]

Posted at 2020-04-03 by Robin

Fri 2020.04.03

Hi @peters, it is unfortunate the electron Gods are fooling with you. I just checked over my cable and watch and for the life of me can't see how a condition as you describe could occur.

• May I ask what device the USB cable was plugged in to that provided the charge current?
• Was this the first time charging had been attempted?
• Is it possible to recall at what percentage the battery was at prior to connecting the cord?

By chance was the cable left plugged in at the USB side, a practice that the enclosed booklet explains not to do, and the exposed pins contacted something metal?

Would you please post a picture. Thanks

> EDIT: > from post #3 below 'There's no booklet in the Bangle.js, just a getting started card' > > YeHaa! I have a KickStarter Beta Bonus!! Just a small 110 page multi-language booklet titled "GPS Sports Watch User's Manual"
This might work if in a hurry. Haven't tested or matched:

https://usa.banggood.com/Newwear-Magnetic-Charging-Watch-Cable-for-Newwear-Smart-Watch-Q3Q8Q9-p-1380461.html?gmcCountry=US&currency=USD&createTmp=1&utm_source=googleshopping&utm_medium=cpc_bgcs&utm_content=frank&utm_campaign=pla-usg-all-pc&gclid=EAIaIQobChMI5aqGvMbM6AIVSdyGCh0rWQnPEAQYASABEgJwyfD_BwE&cur_warehouse=CN

[gfwilliams]

Posted at 2020-04-03 by @gfwilliams

That's a bit scary - I hadn't had a single report, and I have had two just today.

The magnetic charge cable basically connects USB 5v and GND right through. So, if you let it magnetically attach itself onto something metallic and magnetic (keys, etc) it'll short out (it's a common issue with these types of magnetic cables sadly).

It's always a good idea to disconnect from USB when you're done charging. There was a mention of this in the docs, but given the seriousness of it I have made it more prominent and added mention of it a few extra places - banglejs.com/start for one, where it wasn't before.

Interestingly I've never actually hit the issue because every charger I used seemed to have some overcurrent protection. It seems some devices just provide a whole bunch of USB power with no protection though, and in those cases you can get the melting if it shorts :(

I'm sorry you fell foul of this. I bought a bunch of extra cables - I haven't listed them on the shop yet but I will ensure that I do that soon.

a prctice that the enclosed booklet explains not to do

There's no booklet in the Bangle.js, just a getting started card - and there is no mention of it on there sadly.

[espruino-discuss2]

Posted at 2020-04-05 by PeterS

It is good to know the cable is strait through and will short circuit if the pins are connected to the metal housing. I was there when it happened, the watch was charging at that moment, for the third time. I think it got knocked out of its loading position onto the surrounding housing and I did not notice. I smelt the burning and stopped it on time. The plug is melted, as you can see in the photo. My USB power unit has protection against short circuit, only it delivers 3A, so if it does not go above that when in short circuit due to the resistance of the wiring it will continue to think it is charging and not shutoff. I can measure it once i get a new one. Thanks for the link, if this is the correct charger cable, i will get a few, i also wanted some spare to charge when i forget to take the cable with me. I think a warning this can happen would be good.

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[espruino-discuss2]

Posted at 2020-04-05 by PeterS

When Looking for a replacement cable I also found one with short circuit protection, maybe a good substitute if it fits on the watch:

https://nl.banggood.com/Newwear-Magnetic-Charging-Watch-Cable-Short-Circuit-Protection-Design-for-Newwear-Q20-Q18-Q9-Q8-Smart-Watch-Series-p-1548674.html?gmcCountry=NL&currency=EUR&createTmp=1&utm_source=googleshopping&utm_medium=cpc_bgcs&utm_content=frank&utm_campaign=pla-nlg-rm-all-purchase-pc&gclid=CjwKCAjwg6b0BRBMEiwANd1_SJWuGq6FjzVAMTtRhpJ-8i5QqVylmAopCmjW7IbKePx6rkSSgsC7ghoC1O8QAvD_BwE&cur_warehouse=CN

[gfwilliams]

Posted at 2020-04-06 by @gfwilliams

Wow, that's great that there's one with short circuit protection. Not sure if it'll fit but it looks possible!

I just added the spare ones I got to the shop if you need them: https://shop.espruino.com/banglejs-cable

[espruino-discuss2]

Posted at 2020-04-06 by PeterS

Thanks for the link to the shop, i have just ordered three with circuit protection, will test them and give feedback here.

[gfwilliams]

Posted at 2020-05-26 by @gfwilliams

Hi - did you have any success with these cables?

[espruino-discuss2]

Posted at 2020-05-26 by PeterS

Yes, just got them yesterday, they work fine, same charge (about 200 ma) and tested the protection against short circuit. This is a good alternative and I am glad I can recharge my bangle.js without sticky tape :-)

[gfwilliams]

Posted at 2020-05-26 by @gfwilliams

That's great - thanks! Roughly how long is the cable? I've had someone complaining that the existing 0.5m one is too short and I wonder if this might help...