BGN functioning but won't take a charge

[ang...@safecast.org]

Hello Safecasters,

I just finished my first bGeigie build and everything appears to be checking out - with one exception: the battery doesn't look like it's taking a charge. 

- Yellow light won't come on underneath the FIO

- Percentage battery remained at its original 72% on the overnight mini USB charger. However, when I used it today in its mobile mode it successfully logged the journey and the battery went down, as expected.

The unit seems to otherwise function normally. Anyone have experience with this? Thanks!

Angela

[Holger Weiß]

Hi,

the charging circuit of the BGN is not very "sophisticated". It's based on measuring voltage levels and basically can just tell you if the battery is empty or not.

I had the exact same issue and after some research I grabbed a multimeter and checked all my USB chargers with all my USB cables to find the combination that gives the highest voltage (ranging from 4,8V to 5,3V) at the bgeigies end of the cable.

Now the BGN shows 86% charge when charging ends.However I don't think that this makes a big difference in operating hours.

Regards

Holger

[Alberto Villa]

Hi to everybody,

I can give some detailed info about the battery charger (still valid, at least if nothing has changed since my bGeigie was completed in 2017). Just in case somebody with technical experience would like to know a bit more about this part of the circuitry.

Thanks to a power supply unit with an unstable output voltage setting, I damaged this part and had to change it. After a little investigation I was able to get the replacement. It was the single cell Li-Po charge management controller MCP73831T-2ACI/OT, internally preset for 4.2 V and delivering max. 500 mA, mounted on the Arduino board. Absolute input voltage rating is 7 V (and I went a bit over this limit...). See attached pdf where the substitution was described.

Best regards,

Alberto