Gus Calabrese wrote:
> 1)   thanks for all the help
> 2)  Duh, When I said 1 amp relay, I meant 1 amp solendoid.
> The solendoid is indeed energized momentarily.
> 3)  The sensor is looking through beer (1/2 inch tube) and when it sees foam,
> it triggers.  Thus visible light emitter and sensor seemed best.
> I am open to suggestions.
> Gus

It doesn't need to be visible light, anything will do it.

You can use physical electrical contact with the foam, using
two metalic pins crossing the tube, but it will make ionized
metal in contact with the beer, not that it will make it drunk,
but can change the beer taste anyhow.

The LED pulsing very breafly from time to time also works with
low power consume.  But... the 1Amp solenoid power will come
from the little 3V battery???? If yes, forget about the LED
consume... and start to worry about the solenoid.

But, if you are trying to get the beer foam out of the tube
opening a valve or something like that when the sensor sees it,
there are some mechanical ways to do that, since foam floats
and can enter in some vent traps.

Enough for an out of topic, and as far as I know we can't
discuss alcoholic beverages in here, mainly how to produce it. :))

--------------------------------------------------------
Wagner Lipnharski - UST Research Inc. - Orlando, Florida
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