Electrolysis for dummies

[jasen]

Michael wrote:

You just missed the thread on capacitance based level sensors. With
these, the electrodes are not in direct contact with the water so
electrolysis is not an issue.

I'm reading this in s.e.b but yeah capacitance has always seemed a better
way to sense levels to me, does it work well for non-conductive liquids
like oil or gasoline? (conductive sensors can't work there)
can it be used with compressed (non-liquid) gasses?

Bye.
Jasen

 

[jasen]

[...]

Don't most sump pumps come with one already installed? They are a bit of a
pain to adjust, and I have had problems with reliability. Either not
shutting off, or failing to turn on. Sometimes the switch breaks or jams.
Sometimes the float sinks. I think these are fine for sewage plants, where
someone is constantly available to maintain them. But I have a suspicion
the diaphram may be much more reliable.

for plants they use ultrasonics to measure the distance to the waterlevel
as the pumps are of a size that can't be directly switched by a floating
switch.

Of course, you really need two. One to trun the pump off when the level
falls below the setting, the other to turn the pump on whe the level rises.

or a sensor with hysterisis (those floats have it)


Bye.
Jasen

 

[Don Lancaster]

wahtever you do the positive electrodes will dissolve if it contacts the
electrolyte. stainless steel is much better than copper

The hydrogen overvoltage of iron makes stainless steel largely useless
for most electrolysis.

See http://www.tinaja.com/glib/muse153.pdf

And http://www.tinaja.com/glib/glib/energfun.pdf


--
Many thanks,

Don Lancaster voice phone: (928)428-4073
Synergetics 3860 West First Street Box 809 Thatcher, AZ 85552
rss: http://www.tinaja.com/whtnu.xml email: [email protected]

Please visit my GURU's LAIR web site at http://www.tinaja.com

 

[John Fields]

Very impressive Mike...I read it slowly.....you're very fluent on the
subject.

I think what I'm going to do is just get a glass of water and breadboard
different arrangements and look at the results.

I want to use the input of an optoisolator to sense the water level which
will control a pump.....so it's not like the probes will be in the water
long....and just a short random pulse would work.....plus the opto input
takes very little current to "turn on".

I'll have the output of the opto trigger my PIC microcontroller.

I'm just wondering with such little contact with water whether there will be
a problem. (probably)

 

[Jamie]

I've had different problems with sump pumps all my life. Rarely the same
thing twice. Anything with wires, rods, levers, floats, plugs that come
loose, corroded switches, and so forth. I'd minimize the number of moving
parts and keep them protected inside the housing so nothing can get at
them.

Regards,

Mike Monett

i made a water level sensor once using a Ping-Pong ball inside a little
tube that would push against a resistor plate. just sealed the wire,
outer enclosure and it produced a roughly shaped analog value..
never had any problems with it.