[kerryk]

Sotirios,

Thanks, you got it! I forgot that I had to reverse the leads for my smaller pump too. I tried it out with the larger pump and it worked. It starts out with a higher current (I believe the default behavior to trigger the solenoids), then settles to about 1.3A.

Kerry

[kerryk]

Thanks very much for the tips. If I wanted to control a larger pump, can you recommend any DC relays to operate 110VAC pumps?

Kerry

[kerryk]

Sorry, I think I did the ramp test with the supplied power supply. The 12V 2A transformer started at 20V and declined to 12.23 and stabilized by the end of the 90 second cycle. The power output of that transformer was 12.4 V so it looks like the OpenSprinkler is doing what it is supposed to.

So you think running the DC pump at the higher initial voltage should be okay? I’m guessing if its a DC motor it will just spin a little faster initially? I can switch the leads on the pump so it’s not a big deal, but is the reverse polarity output the normal operation for the unit?

Thanks for the help.

Kerry

[kerryk]

I tried connecting the OpenSprikler DC with a 12V 2 amp transformer I picked up. I connected my 12VDC 4.8 submersible pump to station 1 and set it to run for 5 seconds as a test. Pump didn’t run. I hooked up my voltmeter to station 2 and ran it for 5 seconds. It registered -20VDC. I then reversed the polarity of the pump and it did run, but I didn’t want to go longer than 5 seconds. I checked it with the voltmeter with a run of 90 seconds. The voltage starts at 20V and then decreases steadily to about 9V by the end of the run. I’m guessing this is the normal behavior to make it run with the solenoid valves, but I don’t know if this will work with using the timer to keep the pond pump on to fill my flood and drain hydroponic system (needs to be on for 75 to 90 seconds at 12V. I don’t know how the pump will react to the voltage ramp. Any suggestions would be appreciated. Thank you.

Kerry

[kerryk]

Thanks for the feedback. I probably won’t need to run multiple pumps at once, but I got a 2 amp power supply just in case.

[kerryk]

Thanks for the good news. Can you recommend the specs for the power supply to pair with the unit? I expect to control 4 pumps. Maybe 12V and 2 amp?

[kerryk]

Thanks. Programming for the board is something new for me, so I might try the parallel method first. Appreciate the great support.

Kerry

[kerryk]

The attachment.

[kerryk]

The pump is an Aquatec 8851 that I run at 80 psi, the power supply that comes with it is rated at 2A. I’ve attached the current draw table. I’m guessing it would be easier to connect the three stations in parallel, but is there documentation on using the on-board relay? Thank you for your advice.

Kerry

[kerryk]

Thank you. I will give it a try.

Kerry

[kerryk]

Great. I wasn’t sure if sub-second on-times and short cycles were supported, but it looks like this will fit the bill. Thanks.

Kerry

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