Bringing my new system on-line
For several years, my meager 400 watt solar system supplied a bit of power
at my cabin. But, a long-term goal of mine was to design and build a much
larger system capable of powering my 240VAC well pump. This would reduce
fuel consumption on the homestead significantly.
Using a clamp meter I determined that the 1.5hp pump was using 10 amps to run. This Fluke meter also has "in-rush" capability, and measured that starting amperage at 37-38 amps (500 mSec). That means I need a substantial inverter to supply that much power. I selected Schneider's XM6848 120/240VAC inverter you see on the wall here. It has up to 12kw of surge (60 seconds). I still have to plaster up and repaint the wall where the solar electronics got mounted. I ain't gonna leave it like that.
I coupled this to 15-300watt Renogy panels, wired three in series per array, a 3S5P configuration. The 115VDC from each array was funneled through a combiner box which feeds a Midnight 200 charge controller. The Midnight charges a bank of 8 L-16 batteries wired in series for 48V. Here's a pic of the array frame, made out of welded unistruts.
The frame fits over a single steel pipe sunk in 48" of concrete, which allows the array to track the sun left and right. The horizontal stabilizers at the bottom also allow for season angle changes. I call it "Hillbilly solar tracking". Here are the arrays with the panels installed..
Though I did most of the wiring
myself, my BIL is a retired electrician, so I had him inspect my work.
I'll be sealing up the plastic conduit and getting it buried before winter
Last month we flipped the breaker to start the well pump, and the XM powered it up with ease. I'm now in the performance qualification phase of the system. My rule of thumb is to run the pump only while the panels are capable of making >2400 watts of power. This happens after about 9:30 in the morning. If the arrays are swung over to face SE, the batteries are mostly charged by 9am. By noon though, there's enough excess power to bring the batteries up to float. I can continue pumping till about 3:30 in the afternoon if the arrays are swung SW. With the new solar power, I've gotten my 5000 gallon tank up on the hill completely full to the brim!
I have a video of the pump running, but that's too big a file to post here.