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C2 capacitor burned after plugging LIPO battery in
I’m new to the Mayfly Data Logger boards although I have used a couple of Arduino Unos. Today, I was set-up a water temperature sensor for a project me and my team have coming up. I was able to get the senor up and running but as I was put in the finishing touches(adding the solar panel and the lipo battery), I could smell the board staring to burn(I made sure to check the polarity prior). So then I took the LIPO battery out and retried again(big mistake). Capacitor 2(C2) burned out amnd now I’m not sure what I did wrong. Can anyone please let me know what, if anything, I did anything wrong? We have another board we can use for the project and I don’t want to mess that one up too.
The polarity of your battery pack is backwards, which is why your board was damaged. We mention the caution about battery polarity in multiple places on this website, and also in the EnviroDIY Monitoring Station Manual, and specifically in Section 6.1 (https://www.envirodiy.org/knowledge-base/building-an-envirodiy-monitoring-station/). I’m attaching a photo of that part of the manual, showing the caution note and a photo showing the correct polarity. About half of all JST 2.0 battery connectors are backwards, there’s no industry standard that states which pin is positive and negative, so it’s up to the user to confirm the proper polarity before connecting anything. It also appears that the JST connector you have connected to the external power input is also backwards from what we always use with our loggers and accessories.