OpenSprinkler › Forums › Hardware Questions › OpenSprinkler Pi (OSPi) › Some questions › Re: Re: Some questions
Thanks, I’ll give it a test tonight.
Are there any plans for an expansion board that could also allow for sensors? I was thinking a flow sensor at multiple taps, maybe thermometers or soil moisture sensors, etc.
I have 3 main zones for my house, Front, backyard, side of yard. I have 2 pipes going to the front garden, 1 for trees (which I may never use) and 1 for the garden beds (definitely using that). Backyard has 1 for trees, 1 for some veggie gardens which I will use. West Side has 1 for potplants, 1 for garden beds and has it’s own tap and is 30m away from the other tap in the trench I have dug. OSPI will be on the wall about 1-2meters from the tap (in a covered area).
So far I’ll be putting in 7 core .5mm2 wire for the solenoids and running them 30m in that trench, I’ll have 2 solenoids at the West-side tap so that’s 3 of the cores used, was thinking also of using another 3 for the DC positive, negative and signal wire for a flow meter. Not sure though if the AC power will interfere with the signal line on that 30m of cable? Voltage drop over 0.5mm2 for .15A @ 5v looks to be about .3A, so 4.7v would reach the flow meter I guess which hopefully should be enough.
I guess an idea could be an expansion board that uses 24vAC power lines that can run some solenoids, and a data line to send data back to the main OSPI. I would guess it would be 2 wires for AC, and either a built-in AC>DC converter + a common DC ground + signal wire for a total of 4 wires OR have separate AC + DC power inputs + the data line with the DC line having a common ground between the main and expansion?