Comment below
On 9/28/2012 2:39 AM, David Roberson wrote:
Hi Chuck,
[snip]
My supply is current limited and will not increase beyond what it is
set for. I would see my supply voltage drop toward zero if the system
resistance were to head in that direction.
I am positive that I am reading the voltage and current across and
through the cell. On occasions I have recorded the open circuit cell
output voltage as a function of time immediately after disconnect and
it has interesting behavior. This appears to be a quick way to test
the electrolyte condition, but I have not put much effort into
performing calibration.
[snip]
Dave
-----Original Message-----
From: Chuck Sites <cbsit...@gmail.com>
[snip]
I hope your measuring the voltage and amperage going into the
cell(s). When I saw the heat, the current would shoot through the
roof, just like somehow the resistance drops toward zero.
Best Regards,
Chuck
Chuck and Dave: BIG difference right there in front.
One of you is running the supply in constant current mode, and one in
constant voltage.
If the resistance decreases, the first setup's input power will
/decrease /in proportion (I^2*R); and the second, the input power will
/increase /inversely (V^2/R).
So the question might be, does the temperature rise only because the
input power rose, or did it start to rise before the power rose?
My apologies if this was already obvious.
Also, it strikes me that a sudden big resistance drop is sort of
unthinkable if occurring in the bulk of the electrolyte. A flood of new
ions zipping out from some small source (or if an area source, weirdly
synchronized)? But likewise with an interface change: If small, little
effect; if big then weirdly synchronized. But I never did any chemistry.
Dave B.