Journey with Confidence RV GPS App RV Trip Planner RV LIFE Campground Reviews RV Maintenance Take a Speed Test Free 7 Day Trial ×


Reply
 
Thread Tools Display Modes
Old 01-16-2022, 02:51 PM   #1
wls
Senior Member
 
Join Date: Aug 2009
Location: Mid-Mich
Posts: 429
My possible solar setup.

Here is very rough drawing of my rv setup. I'll probably go with 3-180 panels, down to a shut off breaker box,, then to 40 amp mppt controller, to the 4, 6vt battery bank. I will hook the batteries to a 2000 watt inverter(sine) then to my transfer box, then to thr rv distribution box.
(1) need to know when coming out of the panels, do I need to put a fuse before the breaker box, and if so what size.
(2) in my breaker, used just to shut off panels to controller, in case work is needed on something. What size breaker do I need, 63amp 500 volt?
(3)from the controller (40 amp) to battery bank, put a 40 amp ALN fuse?

Willing to take advice on how to run solar panels, series or parallel, imagine that may change of fuse and breaker size.
Not to worried about shade on panels.
Sorry for the rough drawingClick image for larger version

Name:	20220116_122959.jpg
Views:	174
Size:	46.3 KB
ID:	267839Click image for larger version

Name:	20220116_111717.jpg
Views:	127
Size:	70.3 KB
ID:	267840
__________________
2008 Dodge 3500 Dually, Cummins. Amsoil Bypass Oil Filter, 36 Gal aux fuel tank. Mag Hytec Trans pan. Mag Hytec Diff Pan. 6 speed autostick. 3:73, Timbrens, Smarty JR. Equipped.
2016 Cedar Creek 38FB2

2016 Camping Days=38
2017 Camping Days=24
wls is offline   Reply With Quote
Old 01-16-2022, 03:53 PM   #2
Senior Member
 
Join Date: Jul 2017
Location: North of Seattle, WA
Posts: 14,457
Three panels don't lend themselves to a series/parallel configuration. Two panels will double the available current at same voltage. Adding a third panel in series will double single panel voltage but current will be limited to that of the single panel output (and could possibly damage it).

Either stick with the 3 panels you've chosen, connect in parallel, then connect to a PWM controller with greater than 50 amp capability


OR

Add one more panel of the same, wire onto a two parallel, two parallel sets in series, configuration (2P2S), then connect to an MPPT controller with >60 amp capability.

Other than the three panel configuration the rest of your diagram looks OK.

I would use a 60 amp circuit breaker on input to controller from panels, one that can also act as a switch for when you need to shut down solar output. Controllers I'm familiar with have fuses for output to batteries.
__________________
"A wise man can change his mind. A fool never will." (Japanese Proverb)

"You only grow old when you run out of new things to do"

2018 Flagstaff Micro Lite 25BDS
2004 Nissan Titan
TitanMike is online now   Reply With Quote
Old 01-16-2022, 04:12 PM   #3
Senior Member
 
Join Date: Jul 2016
Location: Idaho
Posts: 270
Three panels can be wired in parallel or wired in series, but you should not construct a series/parallel combination with three panels.

If you wire the three panels in parallel:
19.2 volts with a maximum current of 9.38 amp x 3 panels = 28 amp

If you wire the three panels in series:
19.2 volts x 3 panels = 57.6 volts with a maximum current of 9.4 amps.

A fuse and breaker combination is not necessary. A fuse and switch combination is more reasonable. However, considering how often you'll actually use the switch, it is probably more cost-effective to leave it out of your design and simply pull the fuse when needed. The panel provider should have recommendations about fusing their panels.
__________________
Ray Tired Electrical Engineer; ReTired Archaeologist; Author.
California refugee
residing among the great & awesome citizens of Idaho.
Mobile Palace is a 25-ft Prism on a 2015 Sprinter with 200-watts roof solar.

"Don't pick a fight with an old man. If he is too old to fight, he'll just kill you." John Steinbeck
FollowTheSun is offline   Reply With Quote
Old 01-16-2022, 05:30 PM   #4
wls
Senior Member
 
Join Date: Aug 2009
Location: Mid-Mich
Posts: 429
Quote:
Originally Posted by FollowTheSun View Post
Three panels can be wired in parallel or wired in series, but you should not construct a series/parallel combination with three panels.

If you wire the three panels in parallel:
19.2 volts with a maximum current of 9.38 amp x 3 panels = 28 amp

If you wire the three panels in series:
19.2 volts x 3 panels = 57.6 volts with a maximum current of 9.4 amps.

A fuse and breaker combination is not necessary. A fuse and switch combination is more reasonable. However, considering how often you'll actually use the switch, it is probably more cost-effective to leave it out of your design and simply pull the fuse when needed. The panel provider should have recommendations about fusing their panels.
so what would be the better way, series or parallel, this would mostly be used in AZ. A 40amp controller would work for either setup? Thanks
__________________
2008 Dodge 3500 Dually, Cummins. Amsoil Bypass Oil Filter, 36 Gal aux fuel tank. Mag Hytec Trans pan. Mag Hytec Diff Pan. 6 speed autostick. 3:73, Timbrens, Smarty JR. Equipped.
2016 Cedar Creek 38FB2

2016 Camping Days=38
2017 Camping Days=24
wls is offline   Reply With Quote
Old 01-16-2022, 05:31 PM   #5
wls
Senior Member
 
Join Date: Aug 2009
Location: Mid-Mich
Posts: 429
Quote:
Originally Posted by TitanMike View Post
Three panels don't lend themselves to a series/parallel configuration. Two panels will double the available current at same voltage. Adding a third panel in series will double single panel voltage but current will be limited to that of the single panel output (and could possibly damage it).

Either stick with the 3 panels you've chosen, connect in parallel, then connect to a PWM controller with greater than 50 amp capability


OR

Add one more panel of the same, wire onto a two parallel, two parallel sets in series, configuration (2P2S), then connect to an MPPT controller with >60 amp capability.




Other than the three panel configuration the rest of your diagram looks OK.

I would use a 60 amp circuit breaker on input to controller from panels, one that can also act as a switch for when you need to shut down solar output. Controllers I'm familiar with have fuses for output to batteries.
I could add another if needed
__________________
2008 Dodge 3500 Dually, Cummins. Amsoil Bypass Oil Filter, 36 Gal aux fuel tank. Mag Hytec Trans pan. Mag Hytec Diff Pan. 6 speed autostick. 3:73, Timbrens, Smarty JR. Equipped.
2016 Cedar Creek 38FB2

2016 Camping Days=38
2017 Camping Days=24
wls is offline   Reply With Quote
Old 01-16-2022, 05:54 PM   #6
wls
Senior Member
 
Join Date: Aug 2009
Location: Mid-Mich
Posts: 429
titan mike
wondering why you would recommend a PWN

Either stick with the 3 panels you've chosen, connect in parallel, then connect to a PWM controller with greater than 50 amp capability
__________________
2008 Dodge 3500 Dually, Cummins. Amsoil Bypass Oil Filter, 36 Gal aux fuel tank. Mag Hytec Trans pan. Mag Hytec Diff Pan. 6 speed autostick. 3:73, Timbrens, Smarty JR. Equipped.
2016 Cedar Creek 38FB2

2016 Camping Days=38
2017 Camping Days=24
wls is offline   Reply With Quote
Old 01-16-2022, 06:15 PM   #7
Senior Member
 
Join Date: Jul 2017
Location: North of Seattle, WA
Posts: 14,457
Quote:
Originally Posted by wls View Post
titan mike

wondering why you would recommend a PWN



Either stick with the 3 panels you've chosen, connect in parallel, then connect to a PWM controller with greater than 50 amp capability
If in parallel the MPPT will be of no advantage and may actually hinder charging as itvrequires higher input voltages to function properly. Also more expensive.

If the setup was mine I'd add the extra panel, connect in series/parallel, and use MPPT controller. Then enjoy the greater efficiency and quicker battery charging.

For controller size, 4x 180 w panels will produce ~57 amp of charging current. You will need a controller rated for 720 watts/57+ amps output.
__________________
"A wise man can change his mind. A fool never will." (Japanese Proverb)

"You only grow old when you run out of new things to do"

2018 Flagstaff Micro Lite 25BDS
2004 Nissan Titan
TitanMike is online now   Reply With Quote
Old 01-16-2022, 06:37 PM   #8
wls
Senior Member
 
Join Date: Aug 2009
Location: Mid-Mich
Posts: 429
Quote:
Originally Posted by TitanMike View Post
If in parallel the MPPT will be of no advantage and may actually hinder charging as itvrequires higher input voltages to function properly. Also more expensive.

If the setup was mine I'd add the extra panel, connect in series/parallel, and use MPPT controller. Then enjoy the greater efficiency and quicker battery charging.

For controller size, 4x 180 w panels will produce ~57 amp of charging current. You will need a controller rated for 720 watts/57+ amps output.

so just for example: Renogy Rover Li 60 Amp MPPT Solar Charge Controller
800 watts, and 60 amp charge
thanks
__________________
2008 Dodge 3500 Dually, Cummins. Amsoil Bypass Oil Filter, 36 Gal aux fuel tank. Mag Hytec Trans pan. Mag Hytec Diff Pan. 6 speed autostick. 3:73, Timbrens, Smarty JR. Equipped.
2016 Cedar Creek 38FB2

2016 Camping Days=38
2017 Camping Days=24
wls is offline   Reply With Quote
Old 01-16-2022, 08:26 PM   #9
Senior Member
 
Join Date: Dec 2021
Posts: 215
Quote:
Originally Posted by FollowTheSun View Post
Three panels can be wired in parallel or wired in series, but you should not construct a series/parallel combination with three panels.

If you wire the three panels in parallel:
19.2 volts with a maximum current of 9.38 amp x 3 panels = 28 amp

If you wire the three panels in series:
19.2 volts x 3 panels = 57.6 volts with a maximum current of 9.4 amps.

A fuse and breaker combination is not necessary. A fuse and switch combination is more reasonable. However, considering how often you'll actually use the switch, it is probably more cost-effective to leave it out of your design and simply pull the fuse when needed. The panel provider should have recommendations about fusing their panels.
This.

Configure the panels in series and use an MPPT controller. Here is a simple explanation of the efficiencies between the two using your panels. Now, your panels have a maximum output of 540W (19.2V*9.38A*3=540W)

A PWM will regulate the incoming voltage from the panels to the battery. The panels output 19.2v, however the PWM will only use ~14.4V and it throws away the other 4.8v. That is significant; here are your number for all three panels

14.4V*9.38A*3=405W

An MPPT will has the ability convert DC to DC with high efficiency. Here are those numbers with 5% efficiency loss.

18.2V*9.38A*3=513W

So, in your case if you use an MPPT controller you will be able to reclaim 108W over an PWM controller. There are many personal opinions associated with the cost of when to use one controller over the other. My opinion is any PV array over 400W, when wired in series should use an MPPT controller. As a side note, this doesn't apply if the panels experience any shade.

Also, I too prefer to have a breaker in line with my panels solely to be used as a disconnect. When servicing the system, the panels must be disconnected first and reconnected last.
__________________
2022 Cherokee Wolf Pup 18TO
2022 Dodge Ram 2500 6.4l Bighorn
Ballistic is offline   Reply With Quote
Old 01-16-2022, 08:40 PM   #10
Senior Member
 
Join Date: Jul 2016
Location: Idaho
Posts: 270
wls
Connecting the three panels in parallel might improve performance when shadows cast across the roof. That is, if one panel is shaded and the others are not. The shaded panel will suffer significantly reduced output while the other panel continue to perform well. Depending on the shadow, you might lose ⅓, ⅔, or all output. Also, the wire from the junction of the three panels to controller must be large enough to handle the total current. In your three panel installation, about 30 amps.

Connecting the three panels in series triples the output voltage to 19.2 volts x 3 panels = 57.6 volts and reduces the total panel maximum amperage to that of the lowest panel. The entire system output is reduced significantly if any panel become shaded. The wire size for your three panel installation needs to conduct 10 amps.

You say you're not concerned about shadows. In my opinion, with only three panels there is no significant merit for either a series or parallel configuration. Personally, I'd connect them in series to a 60-amp MPPT controller with hopes of adding one more panel. With four panels I'd do as TitanMike would, that is: a two-panel-wired-in-series pair wired in parallel to an 80-amp MPPT controller.
__________________
Ray Tired Electrical Engineer; ReTired Archaeologist; Author.
California refugee
residing among the great & awesome citizens of Idaho.
Mobile Palace is a 25-ft Prism on a 2015 Sprinter with 200-watts roof solar.

"Don't pick a fight with an old man. If he is too old to fight, he'll just kill you." John Steinbeck
FollowTheSun is offline   Reply With Quote
Old 01-17-2022, 02:24 PM   #11
wls
Senior Member
 
Join Date: Aug 2009
Location: Mid-Mich
Posts: 429
So after all this info, great info. Maybe I will go with just two panels, 180, possible 200-watt ones. I can always add a couple down the road. and it will be 2 more if I do.

So, if I choose to go that route, should I go with a 40- or 60-amp MPPT just in case of adding some in the future?

Sorry for all the posts, but I have learned a lot from you all, and hopefully answered some question somebody else may have. Thanks
__________________
2008 Dodge 3500 Dually, Cummins. Amsoil Bypass Oil Filter, 36 Gal aux fuel tank. Mag Hytec Trans pan. Mag Hytec Diff Pan. 6 speed autostick. 3:73, Timbrens, Smarty JR. Equipped.
2016 Cedar Creek 38FB2

2016 Camping Days=38
2017 Camping Days=24
wls is offline   Reply With Quote
Old 01-17-2022, 03:49 PM   #12
Senior Member
 
Join Date: Jul 2017
Location: North of Seattle, WA
Posts: 14,457
When selecting your controller I'd purchase the highest amperage output you would ever expect to need.

Nothing worse than going to expand solar psnel install then find you will now need to upgrade controller.

Larger controllers do cist more but the incremental cost increase is rarely twice as much which you will usually exceed if you have to purchase a second.

"Buy once, Cry once".
__________________
"A wise man can change his mind. A fool never will." (Japanese Proverb)

"You only grow old when you run out of new things to do"

2018 Flagstaff Micro Lite 25BDS
2004 Nissan Titan
TitanMike is online now   Reply With Quote
Old 01-17-2022, 11:49 PM   #13
Senior Member
 
Join Date: Apr 2016
Location: Home
Posts: 255
I'm trying to learn something here.
jeepin1 is offline   Reply With Quote
Old 01-18-2022, 10:16 AM   #14
Trailer Trash
 
Captain Insaino's Avatar
 
Join Date: Dec 2021
Location: Northern California
Posts: 232
Maybe it was one of you guys that recommended this fused breaker...
It worked well for my application in my small battery box. One from my 40a solar controller to the battery near the (+) post and one next to it from the battery to my 500w inverter. It accepts wide wide variety of wire gauges.

https://www.amazon.com/STETION-Reset...s%2C234&sr=8-3

I used this from the panels to the controller (not fused) and then again as a mater cutoff (-) between the shunt and house wiring in the battery box.

https://www.amazon.com/Ampper-Batter...xpY2s9dHJ1ZQ==

Please correct me if I'm giving bad advice.
__________________
2017 Palomino-Real-Lite Mini-RL-177
Typical Boondocking mods
Captain Insaino is offline   Reply With Quote
Old 01-18-2022, 10:21 AM   #15
Senior Member
 
Join Date: Feb 2020
Location: Loveland, OH
Posts: 873
Quote:
Originally Posted by Captain Insaino View Post
Maybe it was one of you guys that recommended this fused breaker...
It worked well for my application in my small battery box. One from my solar controller to the battery and one from the battery to my 500w inverter. It accepts wide wide variety of wire gauges.

https://www.amazon.com/STETION-Reset...s%2C234&sr=8-3

Do not use those. They are unreliable and may fail closed. Lots of youtube videos on them.



Use Bussmann or Blue Sea circuit breakers.
__________________
2015 Chevy 2500HD 6.0 4x4 CC SB
2021 Salem Heritage Glen 290RL
Andersen Ultimate
1200W solar > 412 Ah LiFePO4 > Victron MultiPlus II > Cerbo GX
corn18 is online now   Reply With Quote
Old 01-18-2022, 11:36 AM   #16
Trailer Trash
 
Captain Insaino's Avatar
 
Join Date: Dec 2021
Location: Northern California
Posts: 232
Quote:
Originally Posted by corn18 View Post
Do not use those. They are unreliable and may fail closed. Lots of youtube videos on them.



Use Bussmann or Blue Sea circuit breakers.
Yikes!
__________________
2017 Palomino-Real-Lite Mini-RL-177
Typical Boondocking mods
Captain Insaino is offline   Reply With Quote
Old 01-18-2022, 01:17 PM   #17
wls
Senior Member
 
Join Date: Aug 2009
Location: Mid-Mich
Posts: 429
I was looking at this somewhat complete setup, 400 watt set up, Bougerv 9BB panels. I was looking at the wiring from the panels to controller, looks like the pos hooking to the controllers neg, and the neg to pos. I see the branch parallel. Can someone explain this to me.also any info on the 9BB panels. They want $699.00 for the kit. ThanksClick image for larger version

Name:	20220118_105507.jpg
Views:	76
Size:	72.8 KB
ID:	267944
__________________
2008 Dodge 3500 Dually, Cummins. Amsoil Bypass Oil Filter, 36 Gal aux fuel tank. Mag Hytec Trans pan. Mag Hytec Diff Pan. 6 speed autostick. 3:73, Timbrens, Smarty JR. Equipped.
2016 Cedar Creek 38FB2

2016 Camping Days=38
2017 Camping Days=24
wls is offline   Reply With Quote
Old 01-18-2022, 01:49 PM   #18
Senior Member
 
Join Date: Nov 2021
Posts: 387
The diagram is labeling the male and female connectors. The positive panel wire still goes to positive on the controller and negative to negative. However, I personally would wire this system with the panels in series instead of in parallel. This will give you less wiring issues as the current will be lower and I've found that MPPT controllers love the higher voltage.
__________________
Rockwood Geo-Pro 15TB on order
2019 Ford Ranger
W5CRE is offline   Reply With Quote
Old 01-18-2022, 03:46 PM   #19
wls
Senior Member
 
Join Date: Aug 2009
Location: Mid-Mich
Posts: 429
Quote:
Originally Posted by W5CRE View Post
The diagram is labeling the male and female connectors. The positive panel wire still goes to positive on the controller and negative to negative. However, I personally would wire this system with the panels in series instead of in parallel. This will give you less wiring issues as the current will be lower and I've found that MPPT controllers love the higher voltage.
ok thanks
__________________
2008 Dodge 3500 Dually, Cummins. Amsoil Bypass Oil Filter, 36 Gal aux fuel tank. Mag Hytec Trans pan. Mag Hytec Diff Pan. 6 speed autostick. 3:73, Timbrens, Smarty JR. Equipped.
2016 Cedar Creek 38FB2

2016 Camping Days=38
2017 Camping Days=24
wls is offline   Reply With Quote
Old 01-18-2022, 04:31 PM   #20
Senior Member
 
Join Date: Jun 2021
Posts: 217
It would seem to me that anytime you put these panels in Series that you are just wasting your available power. The controller is just dissipating the extra power from the higher voltage as heat, e.g. your wasting money.

To begin with the power output of the panels is usually at 17 or so volts and you don't charge 12V batteries with that voltage. For a 200Watt panel 200/17 = 11.7 Amps but instead your getting say 13.6V * 11.7 Amps or really 159Watts. OOOPS!!!

IF you look at this on a more industrial scale, e.g. either using all that power during peak load and or storing it then the loss of efficiency would make using solar power a poor choice for power.
NJBreeze is offline   Reply With Quote
Reply

Tags
solar

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Forest River, Inc. or any of its affiliates. This is an independent, unofficial site.



All times are GMT -5. The time now is 05:51 PM.