Thank you. No, I haven't found an answer yet, but your resources seem to offer the best potential. I should have asked "Just Answer" in the first place if there is a low water switch for a solar pump.
Hello, Thank you, XXXXX XXXXX continue to look for a professional to assist you. Please let me know if I can be of any further assistance while you wait. Best,
No answer yet.
Keep it up. If anybody wants to discuss the issue, I'd be happy to do so. At the moment I have no better resource.
The pump is wired directly to, and is powered by, two 2' x 4' solar panels and it works fine. It sits in a 100 gal watering trough that is continuously fed by a usually dependable stream. The pump lifts the water about 80 feet to a storage tank to irrigate a hill-side garden. If the stream supply in interrupted, the pump will run dry, thus the need for a low water shut off switch.
What I finally found is basically a sump pump, but the seller ignored the solar powered part and sent an AC switch. Since it was fairly expensive, I hope I can somehow wire it to work. The switch should open one of the pump wires.
Yours are all good questions assuming they're relevant to the question. Sadly, I'm in California right now and the pump and its data are on Kauai. I won't be back there until August. I thought I was just looking for how to hook up an AC switch to a DC system, perhaps using an inverter or the AC system itself.
If the answers to your questions are needed, perhaps we can suspend the search until I return to Kauai, in which case I'd need whatever info will get me back to you.
It's a small pump yielding about a gallon a minute at the 80' lift point. I think it turns out something like 17.5 V. The solar panels are about 8 feet from the pump, but the wires are probably 50' long. I was trying to connect the switch directly into one of the panel-pump wires.
I have a multimeter, but I forget what the readings were.
Excellent! I don't understand much about relays, wattage, and wire length, so that part will have to be clarified when I have the data. I might be able to get someone to read the label on the panels.
They must be wired in series if your drawing is for parallel. If I remember correctly,one wire from panel A goes to B and the other wires from A and B go to the pump. At present, the only way to shut off the pump is to disconnect one of the wires,
The wires, I think, are #12 solid copper rather than wound, but the short cord I used with the plug is regular household extension wound cord, probably #14. If the overall length of the wire from the panels to the pump is a problem, the excess could be cut out. When I said the panels are about 8' from the pump, I should have said closer to 18' as far as the wire connection is concerned, but the overall length of the wire is about 50'.
Your relay suggestion appears reasonable, but I'd have to be able to ask for the right thing and how to connect it. How is wattage and voltage related to whether the system is parallel or in series? Somebody suggested that an inverter like one used to have a car battery operate an 110v electric drill might work, but I can't picture that.
Anyway, I think you're on the right track. You're the first person that seems to understand the issue. Thanks.
Ok, thanks.If they are series connected then you are boosting the voltage and keeping the current the same as one panel.New diagram below.Now, I can tell you with the length of the wire at 50', it maybe too small.The voltage drops when the wire size is too small, so the pump would run very inefficient and hotter tending to die at a faster timeline than if the voltage is correct.This is where the nameplates on the panels, pump are necessary to determine proper fit and wire size.Also, solid wire is not suggested, only stranded wire should be used. Much better conductor and current carrying especially for low voltage DC applications.Inverter will just change the low DC voltage to AC voltage.That would allow some AC for operating a relay if needed or change the pump to AC, but think the float switch would work on the DC voltage.Changing the pump to AC would require more safety in the wiring etc and cause more difficulty because the low voltage is not dangerous for shock hazards, where going to AC would be.Here again, without a Make and Model, another unknown.If they can read some labels for you, it would be great.Solar panelsPumpFloat switch.Get Voltage, amperage,wattage or anything on the label.Take pictures and then they can be posted right here to look at. Much easier.
I'm supposed to rate your answer when I'm 100% satisfied.
So far, your advice has been excellent, but we're not finished yet because I haven't given you all the answers to what you need to complete your advice. This may take some time.
Meanwhile, I'd give you credit with 5 stars. And I think your advice is worth more than the $15 I first agreed to pay.
Back in business. Here is what is on the back of the panels:
Industrial Solar: Model IS 85J
Operating Voltage: Vmp 17.2 V
Operating current: 4.85A
Open Circuit Voltage: Vcc 21.5V
Short Circuit Voltage: Icc 5.33A
By "luck" with the pump or float switch, I suppose you're asking if they work. Absent any connection to the switch, the pump runs whenever the sun is shining on the panels and the wires are connected.
The switch hasn't been tested independent of the system, but since it's new and the movement of the interior parts can be heard when the canister is tilted from horizontal to vertical, I assume it would work if plugged into a 110 V outlet and a 110 V device was plugged into the switch.
The switch came with a short cord, the plug of which has both male and female accommodations. The only instruction is that the (presumed 110V) pump male fitting plugs into the female fitting on the switch plug and the male fitting of the plug goes into the 110V power source.
It seems to be designed to pump out a sump as may be found in a house basement. The switch is in a float that allows the pump to operate as long as there is enough water in the sump for the float to remain horizontal. When the float turns down, the switch is activated and turns off the pump.
Our challenge is to made the switch operate in a DC, solar powered setting, or to find a switch that is designed for that purpose, if the one we have can't be adapted.
This appears to be what I should have sought originally.
All the devices mentioned seem to be intended to turn a pump on when a tank gets low. We need it to turn the pump off when the water gets low and back on when the water goes up.
The description of one device tells of changing from normally open to normally closed by reversing the float. Is that what we want and what's all the part about relays and contacts?
The one you need would have open contacts when the water is low and closed when high so the pump runs with water.Most of the floats have both so it is not a problem and they can work either way, just swap one wire.To me (manufacturers are very different), normally closed will be closed when low and open when high.Normally open is opposite, open low and closed high, what you need.Those 2 were examples only of what you need.Without the pumps amperage and voltage rating on its nameplate, I cannot pick the one out that would definitely work.The one I posted you were asking on relays etc was only rated for 1/2 amp, so that is why they mentioned something else to actually activate the pump.They have higher rated floats to match your pump, but we need those numbers to find yours.
Following your advice, my plan is to get the Amico switch, the 781-1C-12D and take them to Kauai along with your diagram, probably in August.
Assuming that's the answer to my question, I quess I'm ready to Rate to Finish.