Re: [APD] The siphon saga continues...need safety shutoff!

["S. Hieber" <shieber at yahoo_com>]

A venturi on a powerhead can do it, if everything works
just right. Better, a small pump that can handle air or
water and which turns on when the sump pump comes on is
just the ticket. Tom's/Oscar makes one called the Aqua
Lifter. If you rig a monostable timer (the triggering event
starts it but doesn't keep restarting after the timing
circuit shuts it off), you could set it up to come on
whenever power comes back on and starts the sump pump but
the timer shuts the Aqua Lifter down after a few minutes,
by which time it's work is done. Even a simple circuit
based on the venerable an NE 555 would do the trick. Lots
of circuits out there on the web for that 30+ year old chip
-- here's just one:

http://www.uoguelph.ca/~antoon/gadgets/555/555.html


Or you coul djsut let the little pump run whenever the sump
pump is running.

Scott H.
--- Andrew Mitchell <andrewm at cse_unsw.edu.au> wrote:
> >From my experience if a syphon has no/little flow for a
> few days 
> (will differ depending on diameter and maximum height
> etcetera) then air will come out of solution
> gradually and end the syphon. I haven't yet figured out a
> good way around the problem.


=====
S. Hieber

-  -   -   -   -   -   -   -
Amano Returns
to the AGA Annual Convention
Nov 12, 13 & 14, 2004 -- Crystal City, Virginia

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