Hello All,It has been a while since I have been here. I need to come back more often. I have a 2016 fuzion 345. Love the tech but man does it eat power. I did put 6 6 volt batteries and that will get me through a weekend, not much more. I have an onboard gen but I get away for peice and quiet.Because I use power I have bought 2 - 280 panels and all the trimmings. Last item I need to know. Which is better parallel or series. I know that pannenels in parallel is more volts, series is more amps. I just don’t know which set up I should do. Which is better for battery health? Which is better for quicker recharge. I will be adding an inverter later.I would like your thoughts.

Actually, in parallel you add the amps, and in series you add the volts.The big factor there is the Voc limit of the solar controller which will fry if you go over the Voc limit at all, no second chances.Unless there is much shading in your situation, there is no advantage in amps to the battery either way. If there is some shading, parallel is better for daily AH haul.

Those are likely 60 cell modules with a Vmp or around 30 volts. You will need an MPPT controller to allow them to charge your 12v battery bank without wasting most of the power. An MPPT controller will have a maximum Voc. Your panels are likely around 37 Voc at 25 degrees Celsius. When it gets really cold that will likely increase to around 45 Voc. If you put them in series make sure your controller can handle the 90v input or you will fry it.Volts add in series, amps add in parallel.

BFL13 wrote:Actually, in parallel you add the amps, and in series you add the volts.The big factor there is the Voc limit of the solar controller which will fry if you go over the Voc limit at all, no second chances.Unless there is much shading in your situation, there is no advantage in amps to the battery either way. If there is some shading, parallel is better for daily AH haul.You are right. I did get it backwards. I was going off this site.http://solarloco.com/blog/diy-solar-panels/the-difference-between-series-and-parallel-circuits/I have a 40 amp controller. It can handle 1560w/12v. 72 cell Voc < 46v.

I was thinking more amps would charge quicker. Much like more amps on small electronics. There just not much information to read about benifets to more volts vs amps.

y22man wrote:I was thinking more amps would charge quicker. Much like more amps on small electronics. There just not much information to read about benifets to more volts vs amps.It does not work that way. Total power to the batteries is governed by the MPPT and series or parallel will not significantly matter when it comes to total power. One advantage to series is that the wire gage between the solar panels and controller does not have to be as large for series wired panels.

Solar panels in series or parallel? | Good Sam Community

Lwiddis
Explorer II
Sep 20, 2018
"You can over-panel the MPPT controller somewhat with no ill effects, because the controller self-limits the amps to its rating. (40 amps)"

This may depend on the manufacturer of the MPPT, BFL. WindyNation says a big "NO." I ask about five 100 watt panels for their 30 amp MPPT...four only.
y22man
Explorer
Sep 20, 2018
Here are the photos. I don't have a pic of the roof. It is pretty straight forward up there.

Battery box. 4x6 volts and charge controller.

Main connections off these 2 6V batteries.

Routing of cables from roof to basement.

Remote monitor just inside the door in the hallway to master bed room.
time2roll
Nomad
Sep 01, 2018
y22man wrote:
I would like to have the inverter installed, but finding documentation on that install is limited. By that I mean, nothing with an existing T-52 transfer switch. I want to provide all the 110 outlets but the ac, fridge, fireplace, and microwave with the inverter.
What wattage? 350 watts or less is fairly simple.

Yes you will need to possibly put the converter and fridge on a separate circuit. Then use a small transfer switch to power the branch circuit of choice. Possibly 2 switches to power two branches.
CA_Traveler
Explorer III
Aug 31, 2018
y22man wrote:
With the smoky skies we had due to wild fires the output was severely down.
Lucky you! I was just east of Seattle and it was downright unhealthy+ as in red+ from the monitors. Two days ago it cleared up and steady drip drip last night. But headed south today.

I love those night rains and clear air the next day. :B
mountainkowboy
Explorer
Aug 31, 2018
let see if that works....

Great link....THANKS.
red31
Explorer
Aug 31, 2018
y22man wrote:

I wish I could post pic directly on here without a url.

This site will let you create a url from a pic on your computer, ya just copy the created url and past it in a message.

http://photoposting.is-great.net/
y22man
Explorer
Aug 31, 2018
The system has been installed for a little over a month. Works great. Clear sky’s are important. With the smoky skies we had due to wild fires the output was severely down. The last week or so the performance has been much better.

Even with the smoky skies this system charges to full every day. We are still in the conserve power mode. Kids are respectful of power and water use when we camp. We have been out 3 times since the install. Last week I finally ran the control wire inside.

The real test is when we pull the trailer to the Utah Utes football games tailgating. I would like to have the inverter installed, but finding documentation on that install is limited. By that I mean, nothing with an existing T-57 transfer switch. I want to provide all the 110 outlets but the ac, fridge, fireplace, and microwave with the inverter.

I wish I could post pic directly on here without a url.
CA_Traveler
Explorer III
Aug 03, 2018
Here’s another illustration for bypass diodes showing how they operate.This is for 3x 24V 60 cell panels in series with 3 bypass diodes per panel. This shows 20+30+20 = 70V. The available amps are dependent upon the available light as shown in the typical IR curves. There is actually a small voltage drop for a conducting diode of about 0.5V. So 19.5+30+19.5 = 69V available to the MPPT controller at the given amps.
red31
Explorer
Aug 03, 2018
looking at a ole irradicace plot of 2013 from Cedar city UT, @ 9am a flat panel should be collecting only 600w/m^2 (60%) peak of ~1000 should be 12-12:30.

https://midcdmz.nrel.gov/apps/plot.pl?site=USEPCC;start=20100713;edy=31;emo=12;eyr=9999;year=2013;month=08;day=8;time=1;zenloc=19;inst=3;inst=4;inst=5;type=plot
y22man
Explorer
Aug 03, 2018
I am doing a test. I ran the batteries down this week. I then turned on the panels today at 9:00 am. Clear blue sky, 76*. It seems to me I am only generating half of my potential. 30.1v and 9.7 amps.

Panels are connected to a Y split cable with a single positive and negative run to the charge controller.

I am sure this is more than enough but seems low.

Ok, so I am a dope, or a slow learner. It looks like it is working as installed. The panels are 30.4v and 14.2a. learning, learning, learning.

Jay