diy solar

diy solar

ez ground mounting system

Well done! That looks like the way to go.

Curious why you don’t house the inverter/charger/battery at the panels and run AC to the house. Security?
 
Well done! That looks like the way to go.

Curious why you don’t house the inverter/charger/battery at the panels and run AC to the house. Security?
The answer is in the details of the original post
next wiring three strings of 14 = 440vdc
Even if he ran 240VAC, the loss across the line would be greater than the 440VDC.

For the purposes of most DIY projects, AC vs DC is meaningless when it comes to line loss. It has everything to do with high voltage vs low voltage.

It turns out that AC is actually slightly less efficient for long-range distribution. In the past, it was so difficult to step DC voltage up and down that it was impractical to run DC over long ranges. With modern power electronics, it is now more feasible to run High Voltage DC and we are starting to see high power distribution over DC.
 
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I was more concerned about safety. I’m pretty comfortable running AC anywhere. Don’t much care for DC.
 
filter guy has it right i was able to run 3 pair of 14 gauge with less than3% loss vs 1 gauge for 240ac saving about 800.00
 
Voltage drop on the input to a switcher (MPPT) is made up for by drawing more current.
Voltage drop in regulated AC doesn't get compensated for, can brown-out motors, etc.

It's only during peak production times that PV IR drop is big, less during bad days or other times of day.
But, if you have 5kW of PV during sunlight and produce 1kW AC continuously for small loads, then IR drop of AC would be better.
 
That's very cool! COOLER THAN THE OTHER SIDE OF THE PILLOW
I wanted to get something that was engineered and stamped by PE. So, this is what I did. PE's freakin LOVE concrete, it took 90each 80 pound bags for my 3 arrays that mount 9 panels each. I am also attaching the pic of the slope vs wind limit spec sheet for your info. Well done! ALL THE BEST!!!
 

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@partytyme how are you handling panel end clamping? I used Unistrut and mid clamping was easy - just a bolt and washer, but when I tried to use a bolt and washer as an end clamp, the washer would tilt over as I tightened the bolt and ended up not holding.

Do you have pics of your end clamping? (the pics I've seen don't seem to show the finished end clamping)
 
The clamps fit inside the rail, then when you tighten they squeeze the panel to the rail while anchoring them selves in place. The clamps slide up and down and the rails slide back and forth making this very easy to adjust to any panel size. These come from Northern Arizona Wind and Sun. ALL THE BEST!
 

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I'm curious: Why the slope you chose? How deep are the holes for the frame?
Please consider using guy wires on the four corners to secure the entire unit during high winds when the ground is wet.
How much wind would you expect this to handle? What part on the globe do you reside?
Thanky
 
The clamps fit inside the rail, then when you tighten they squeeze the panel to the rail while anchoring them selves in place. The clamps slide up and down and the rails slide back and forth making this very easy to adjust to any panel size. These come from Northern Arizona Wind and Sun. ALL THE BEST!

Is that a splice in the middle of the rail?
That would significantly affect strength. Although, if a clamp keeps top edge aligned (as shown in your picture), long strap apparently bolted to bottom holds it when in tension due to wind pressure.

My rails are all one piece, 18' long and supported by 2 or 3 horizontal pipes.
I think splices are only for applications like roof mounting where each rail has multiple supports.
 
Yes it is a splice. It is about 2/3 vs 1/3 (not in the middle - would be in the middle if I had a 4 tall array instead of 3). There is a big chunk of metal inside the rail and those clamps make it all tight. This stuff is PE approved so I call it good. I would question the clamps on the panels before the rail splice. (that's just me with my hands on it) I agree, splices suck. You could probably get these rails whole somewhere but then they would ship via tractor trailor. The UPS shipping made me VERY happy as access to my house is dicey.
 

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The clamps fit inside the rail, then when you tighten they squeeze the panel to the rail while anchoring them selves in place. The clamps slide up and down and the rails slide back and forth making this very easy to adjust to any panel size. These come from Northern Arizona Wind and Sun. ALL THE BEST!
Are you using Unistrut? Looks like you might have changed to aluminum solar rack rail
 
I last bought some surplus 17' heavy-duty Unistrut rails. Arranged truck shipping to a freight terminal (couple $hundred), and picked it up with my pickup that has roof rack over bed and over cab to front bumper.
Forklift couldn't quite make the height with pickup in the parking lot, had to slip on from end and muscle it over to fit full length.
If I parallel parked at the loading dock, then it would reach.
 
View attachment 62339View attachment 62340View attachment 62341
i came up with a cheap way to ground mount my 42 panels this worked for me! i ended up with a 62 degree angle and pre drilled all the poles used 4x4x8 in the front and 4x4x12 in the rear took three days with my wife and one other friend helping , you mount the middle bottom panel first and work both ways only bolting the uni strut on the bottom with 20 inches hanging over the 1 inch pipe using uni strut nuts hollow side toward the pipe until you get the 2nd row mounted then bolt threw the top pipe my panels have mounting holes every 34 inches and you need 31.5 inches from last mount hole to the next panel starting hole used a 3/4"piece to space the panels when we stacked them worked great drilled and bolted the uni strut to the top pipe after the 2nd row was in place allowing me to slide the channels up to keep them level. i leveled the pipes as we set them the 4x4 all in the ground at least 42" just cut off the bottoms to keep it level pre drill the pipe holes with a 1.5" wood bit in a drill press to keep them straight my angles were off but it did not matter the panels cleared by inches anyway . next wiring three strings of 14 = 440vdc should work 210 feet from the house 14 gauge three pairs i hope
parts used

panels to uni strut
1/4 20 fender clips on panel bottom
1/4" fender washers
1/4 20 bolts 1"long Phillips head

uni strut to pipe 2" 5/16 bolts
uni strut track nuts 5/16
i placed 8 steel t post with hose clamps at 55 foot and used a transit to get my strings with kara beaners straight that gave me room for a tractor with a auger to drill the holes and i could pull the strings as needed tank care mike b
Do you have any shading issues in the winter? (1st row of panels shading the 2nd row of panels)
 
I made a super short vid to illustrate shading on my panels. Hope you find some value in it.
Shade effect on solar panels
Nice video. The impact of shading is very dependent on the design of the panel and the use of bypass diodes.

Many modern panels are arranged in 3 groups of cells with a bypass diode for each set. If one of the cells is shaded, it will impact the output of 1/3 of the panel, but the bypass diode allows the other 2/3 of the panel to continue to produce.

The grouping of cells is often 3 stripes along the long dimension of the panel:

1647662554079.png
If the panels are mounted with the long edge parallel to the ground, then as the sun hits the top zone in the morning they will start producing before the rest of the panel is in the sun, and as the next two zones get sun the production increases. In the evening, the cells lose the sun in reverse order.
 
Nice video. The impact of shading is very dependent on the design of the panel and the use of bypass diodes.

Many modern panels are arranged in 3 groups of cells with a bypass diode for each set. If one of the cells is shaded, it will impact the output of 1/3 of the panel, but the bypass diode allows the other 2/3 of the panel to continue to produce.

The grouping of cells is often 3 stripes along the long dimension of the panel:

View attachment 87870
If the panels are mounted with the long edge parallel to the ground, then as the sun hits the top zone in the morning they will start producing before the rest of the panel is in the sun, and as the next two zones get sun the production increases. In the evening, the cells lose the sun in reverse order.
I tried an experiment with my panels. I have mine as 3S-4P. I took one panel in the series and covered it to see if that would kill the whole bunch. I found that the other 3 sets of 3 panels still produced and were not affected by the one panel. I decided that a blocking diode was not necessary for my setup. Your panels may be different.

It is an easy test. Just monitor your output before covering a single panel before and after to simulate the diode.
 
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