Beginners Solar Charging Install

[jbailey]

Jim,
I just had a light-bulb moment in terms of wire sizing. If I wire the panels in series then only the voltage increases and not the amps? I would have assumed both did, but that makes sense the the MPPT converts to the right voltage with the highest Amps to go into the battery. Therefore I would run 10AWG even from 4 panels (in the future, just add two more in series if needed) in series down to the MPPT and a 6AWG from the MPPT to the battery, this would allow all the voltage I had to come down to the MPPT then as much as 50 Amps (max rating) to the battery.

Right? - Ben

[TucsonJim]

Yes sir. Just like when you wire two 6 volt batteries in series to get 12Volts. It only increases the voltage and not the current. I started with two panels in series, and then added another panel a few weeks later, also in series. All it did was increase my input voltage, not the current. Now you can see the real benefit of a MPPT controller. Taking that higher voltage, dropping it down to the appropriate battery voltage and increasing the current to the batteries by doing so. You could probably get away with 12AWG for the system, but I like to over design things, so that's why I went with 10AWG.



Jim

[jbailey]

Ok, so after much head scratching and reading about the potential drop in performance in partial shading for panels wired in series I decided to diagram out the system options. I would appreciate any input people have on the through processes so far.



Thanks, Ben

[jbailey]

I have finally started with the battery compartment. Here are the pictures so far. More to come.

[jbailey]

I have finally finished the Panel & charge install and have POWER! Oh happy day!
Here are a few pictures from the Roof. I ended up with 4 165W Everbright panels and wired them in series to a combiner box. I know that was not necessary, but if I ever want/need to switch to parallel I ran 4AWG from the combiner down to the Solar Charger. The 4 Panels are wired with 10AWG solar rated cable. Those all go to an AM Solar combiner box. The placement of the combiner box required the removal of the existing vent. I replaced the existing vent with the Lippert 360 siphon vent and had to make my own collar/bottom out of a bell housing cover from Home Depot.

[jbailey]

Next came finishing up in the battery compartment. I brought the two 4AWG wired down into the basement through the chase that the vent pipes go up, after the fear of drilling the hole, this actually worked very well. Then across the top of the basement and into the battery compartment. The negative goes straight into the MPPT controller and the positive goes to a 50Amp breaker. From the MPPT on the positive side goes through another 50 Amp breaker and the negative side go to breaker bars and then through a On/Off switch on the positive side to the battery. I also took the "dome lights" from the basement and battery compartment and mounted them on the ceiling for more lighting and not directly in your face, but don't have a picture of that. Also went ahead and insulated the walls between the propane and battery compartment and installed 1/2 plywood so I can mount things.
Attachment 8019Attachment 8020Attachment 8021Attachment 8023Attachment 8024

[jbailey]

Lastly I installed the battery monitor next to the control panel. I ran the wire up the same Chase and into the void behind the panel, drilled a hole and installed. The one problem with the placement is that when I remount the panel the big bundle of wires that GD has behind the panel knock the Blue Tooth dongle out and I cannot get it to stay for the life of me. I would have mounted the monitor either much lower on the same side, or if room permitted on the far side (but it did not with mine). Until then I installed the blue tooth dongle on the MPPT and actually am pretty happy with that as I can get a battery voltage off that as well, but not State of Charge % or anything else.

[jbailey]

I finally finished installing the inverter and moving the EMS protection into the battery compartment. I also custom fabricated a battery box out of HPDE plastic for two L-16 batteries. I only got a couple of pictures but can add more if anybody is interested. I ordered a control panel for the solar/inverter/battery charger and did not have room with the silly way they wired in the existing panel so I had a new one made by Front Panel Express. This was a ton of work, but I am super happy with the outcome. We just spent a week at Burning Man and I could even get the AC to come on via batteries, but only for a couple of minutes. So I only ran the generator to run the AC, with the solar I did not need it to charge the batteries.

[Keebler]

While the entire project came out great, the Control Panel is especially impressive. Thanks for sharing!

[J&G garage]

l just drooled all over my keyboard. Nice job!