by Edwardo
Pump controller/timer – control that nutrient..
7:39 pm in electronic components, energy consumption, Nutrients by Edwardo
After problems with not getting enough nutrient to my system (stalling air-lift) I now have the opposite problem, waterlogged plants!
The airlift is providing too much flow and the seedlings are getting too much watering – there cannot be enough air getting to them
After having a good laugh at the prices of interval timer/switch units I have decided to construct an electronic circuit to do this.
That may sound a big deal – but as we don’t care too much about the accuracy of the intervals or the duration of the “on” period I should be able to produce a very simple circuit (cost circa £8 – £5 if you already have a spare 12 volt supply kicking around) to swith the pump on for say 30 minutes and switch off for say 2 hours (but I will make the periods adjustable)
I will upload a circuit when it’s prototyped but it should be within the capabilities of anyone who can use a soldering iron.
OK I’m uploading a circuit BEFORE it’s prototyped/tested so don’t complain if it does not work!
untested v1 - HyTime
Cheapest timer I came across was 5 bucks and it does the job for my lighting. I picked up an electronic one for about $20 for the nutrients to control down to minute levels.
Your solution might be either finding a way to increase the drainage or maybe using a flow regulator for the drips. You would need a top reservoir for that, and possible an overflow return pipe.
Just as a side note, if you are not planning on opening up the pump, your going to have to play with AC voltage and use a relay. Not sure how cheap that solution is going to be by comparison unless you already have the parts.
I was looking into something similar controlled from a serial cable, and software controlled by a computer, for an unrelated project some time ago. Came across links like this:
http://www.bolis.com/amillar/electronics/serial-port-control-power-switch
Ultimately it might be cheaper to pick up X10 equipment though by the time you figure out the parts list.
I have a circuit designed now, £5 covers all new parts and the AC relay! – very simple analogue/capacitor retriggering delay circuit (1 cmos quad gate, 1 relay, 1 transistor, 5 capacitors, 5 resistors) who needs computers/digital!
I probably will add a top reservoir and overflow but not drippers (don’t they tend to get clogged up with dry deposits of nutrient?) more so I can feed 9 columns at once.
Sounds great! Can you post schematics?
sweet, thanks!
Our timer cost $14, and allows us to turn on the pump at 15 minute intervals. We cycle it on for 15 minutes every hour when light, and 15 minutes every 2 hours when dark.
Just adding this link in case people decide to persue similar projects:
http://www.makershed.com/ProductDetails.asp?ProductCode=MKPS01