Welcome to EnviroDIY, a community for do-it-yourself environmental science and monitoring. EnviroDIY is part of WikiWatershed, an initiative of Stroud Water Research Center designed to help people advance knowledge and stewardship of fresh water.
New to EnviroDIY? Start here

Reply To: Case for Lower Threshold Voltage on Mayfly Stations

Home › Forums › Mayfly Data Logger › Case for Lower Threshold Voltage on Mayfly Stations › Reply To: Case for Lower Threshold Voltage on Mayfly Stations

2021-03-02 at 4:44 PM #15188
Jim Moore
Participant

    Couple of clarifications:

    • The discharge is a fixed load of 22Ω so ohm’s law works!
    • My question is why is the Mayfly station drawing less and less current as it approaches 3.3 Volts?  Yet the 4G modems continue to work and upload the data.
    • I believe that Shannon said that some older sd cards tend to cause current draw during sleep mode.  Maybe this is what is happening.
    • Matt- I am interested in your coulomb counter?  Where can I get one or is it home brew?
    • I have learned that not all Li-ion batteries are equal in terms of stated Ah capacity.  I bought some from Amazon rated at 4.5 AH yet they were less than half the size of the 2.5 Ah batteries I got from Adafruit!  And the JST connector polarity was reversed!

    Cheers

    -jim