Volt() timing weirdness while potty training Carl


I have been working on “potty training” Carl. He needs to recognize when he is:
a) Charging - don’t get off the pot
b) Trickle Charging but not thirsty yet - Can get off the pot when desired
c) Trickle Charging and down to his “need juice” limit - time to get off briefly, then get back on
d) Discharging but not thirsty yet - play hard
e) Discharging and down to his “need juice” limit - time to get back on the pot

So the weird thing if I measure battery, measure distance, measure battery, the second battery reading will be 20-70 mv (0.020v - 0.070v) less than the first reading.

If I put a sleep(1) before the second battery reading, the second reading will always be 0-60mv greater than the first reading.

Not that 0.07 volt variability is that big a deal in 8-12v, but the plus/minus consistency with and without sleep seems weird.