Backyard Aquaponics
A place to discuss aquaponics

Course I did Sleepe.
but for this switch, discs as jimmy drew would not work, as you would need the plate to be mounted vertical as it passes through the sensor, not horizontal.

If Jimmy gets a stiff switch, and a float on a shaft, as I mentioned earlier, his idea will work nicer.
But switches gum up if they're mechanical.

Which means it could be fairly slender?

KP not much interested in electronic switching devices for AP systems. Only pointed it out as an option as there is not much to stuff up in them.

no they're nice like that sleep, it just wouldn't be so simple to design an object to interfere that would be linesd up so precisely. Linear alignment sucks, it's one of the hardest things in the industry, making two tracks not bind.
But I see your point, and appreciate the link, it has given me plenty to think on.

someone correct me if I'm wrong, But hasn't LKB already made/designed switches for this??? Might be a good idea to look at his system thread and then ask him how they are going (just a thought )

from this page on....

http://backyardaquaponics.com/forum/vie ... &start=120

Cheers OB,
I just started wading and decided it was too late and I'm too tired, got through 4 pages though :-)

its stupid the way you can only go through a page at a time

Hmmm Les uses a single throw float switch, with a latching actuated valve... I like it. Question how does he reset the door actuator to 'closed' I assume he has 2 'bottle' switches.

later on in the thread he had trouble with rust due to the high o2 content of AP water....I think the link rod rusted away..

VB, they lost you on page three with opto isolators, huh? LOL

If I were to want to use 2 float switches, and was reasonably certain they wouldn't gum up. I'd use these.
Reed switches operated, and designed to plumb into the side of a tank.
They're a tad pricey, and you'd definitely need 24VDC and a contactor but hey, they're aweful sexy :-)

Stainless bolts aren't hard to come by... he should try that, the design is nice, very simple, and those bolts'll never corrode due to spark erosion - exactly what I mean by over-engineering

I picked this up from a client who bought it by accident. Not what he wanted... :-) I love scrounging brand new stuff

I like shiny things

They come in black plastic too OB, I'd not want you sticking your head in the tank all the time and trying to bite it :-)

Plus, you know how those things work KP? Reed switches..... I think they are a very versatile component as you have pointed out. The plastic float switches in jaycar can be made for two dollars, or buy them for $20.

If you are worried about on/off, have the float switch trigger a 555/556 timer or a latching circuit. Plus latches relay or triac (cheaper), 555 timer starts 1-15min timer, timer latches pump back on, process repeats.

My number one concern is that: MOVING PARTS can and do fail. I don't trust anything that could be interfered with or blocked or whatever.

I have two $10 pressure sensors on their way, SAMPLES of course... hehe. Anyone who knows anything about electronics know how to get lots of FREE goodies.

I am going to lay Cat5 Cables to every tank and GB, under the paving and up through the leg of the growbeds. Green/Orange for Pressure Sensor, the other pairs two for valves at a later stage. It will all run back to a base station and can potentially tell me anywhere in the world what level my tanks are at. Then run a pressure pump off the rainwater tank to auto top off every day/week. Simple for me but way too advanced for most people. So in that case what is wrong with a simple 240V timer that everyone else is using?

Yup I knew that

Yeah I worry about moving parts too. Just wanted to brag about scoring the switch

Where you getting pressure sensor samples? Maxim, national or analog devices? AD were always harder to get free stuff from...

Pressure'd be nice, CAT5 I'd not recommend. get some 8 core data cable, rs232 stuff. Much more reliable and much less lossy.