Solar Install wire diagram

Oldcow

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Sep 3, 2012
Posts
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Location
Eastern Canada
I have acquired most of what I need for my new system. I will not be doing the install, but I still like to understand the wiring.

I am most interested in where any shut off switches, bus bars and fuses should go. So far I am thinking shut off switches between the solar panels and the MPPT, buss bar (maybe Lynx Distributor Power in) between the 3 MPPT's and the batteries and between the batteries and the inverter. For the wiring, from the panels the MPPT I have read 10 gauge is fine. I have yet to really dig into the size for the rest.

What is the best way to connect the batteries? Series, parallel or both?

Here is what I have and what I will be installing;
2 Rich 200W panels in series to a MPPT 100/50
2 series of 4 195W panels down to 2 MPPT 150/60
3 LiTime 280 ah batteries
Victron Multiplus 3000 2 X 120 inverter
1 Victron smart shut

I would appreciate any simple wire diagram drawing to a similar type system just to get my head around it. And if one exist that I can change to my needs that would be awesome as well.

Oldcow
 
Overall it looks like you will have a quite robust system. Could you explain why you need two controllers for your 195-watt panels? Check this site to understand cable sizes. Yes to busbars for the batteries and switches between the panels to the controllers and from the controllers to the battery busbars.
 
Overall it looks like you will have a quite robust system. Could you explain why you need two controllers for your 195-watt panels? Check this site to understand cable sizes. Yes to busbars for the batteries and switches between the panels to the controllers and from the controllers to the battery busbars.
Speaking with Victron, it made sense to them to have 2 smaller controllers than 1 large one and i believe it was also less expensive.

Are you suggesting then 2 buss bars as I stated in my original post?

Also any comment on how to connect the batteries?

I will check the link for cable sizes, thanks.

Oldcow
 
Speaking with Victron, it made sense to them to have 2 smaller controllers than 1 large one and i believe it was also less expensive.
OK, just more to manage.

Also any comment on how to connect the batteries?
Use both a positive and negative busbar. Using cables sized to fit your largest expected draw, wire the battery terminals to the busbar. The negative busbar is then connected to your shunt and then to a busbar for connection to uses throughout the coach. The positive busbar (at least on my setup) is connected to a master switch, then to a fuse, and then to a positive busbar for applications.
 
You say you are not doing the installation yourself but the questions are pretty specific, which the installer should be able to answer. Are you using an experience installer that will know the correct placement/sizing of fuses, cabling, cut off switches, etc.? Just want to make sure... Looks like you'll have a robust system.

One suggestion if you haven't already purchased the Multiplus...consider going 24V vs 12V. It would be more efficient if you plan on heavy loads. Though admittedly your system (and mine) are just on the cusp of where 24V starts to make more sense. Either way it will be fine, but if I had mine to do again, I would have gone 24V although 12V has not caused any issues after a couple of years of heavy use.
 
You say you are not doing the installation yourself but the questions are pretty specific, which the installer should be able to answer. Are you using an experience installer that will know the correct placement/sizing of fuses, cabling, cut off switches, etc.? Just want to make sure... Looks like you'll have a robust system.

One suggestion if you haven't already purchased the Multiplus...consider going 24V vs 12V. It would be more efficient if you plan on heavy loads. Though admittedly your system (and mine) are just on the cusp of where 24V starts to make more sense. Either way it will be fine, but if I had mine to do again, I would have gone 24V although 12V has not caused any issues after a couple of years of heavy use.
I agree that it is worth it to consider the 24v system with your size system.
 
I have acquired most of what I need for my new system. I will not be doing the install, but I still like to understand the wiring.

I am most interested in where any shut off switches, bus bars and fuses should go. So far I am thinking shut off switches between the solar panels and the MPPT, buss bar (maybe Lynx Distributor Power in) between the 3 MPPT's and the batteries and between the batteries and the inverter. For the wiring, from the panels the MPPT I have read 10 gauge is fine. I have yet to really dig into the size for the rest.

What is the best way to connect the batteries? Series, parallel or both?

Here is what I have and what I will be installing;
2 Rich 200W panels in series to a MPPT 100/50
2 series of 4 195W panels down to 2 MPPT 150/60
3 LiTime 280 ah batteries
Victron Multiplus 3000 2 X 120 inverter
1 Victron smart shut

I would appreciate any simple wire diagram drawing to a similar type system just to get my head around it. And if one exist that I can change to my needs that would be awesome as well.

Oldcow
Your wire sizes depend on the max volts and amps expected on each cable run.

I understand having a separate controller for the 200 watt Rich panels. However, I question the need for two controllers for the other 4 panels. I would wire two panels in series and then wire the two pairs in parallel to a single controller.

As far as connecting the batteries, run a cable from each battery to a Buss Bar (one buss bar for Pos and one buss bar for Negative) and then attach your load to the buss bars.

As far as wiring diagrams go, everybody's wiring is going to be unique to their system/coach. Sound Sailor pretty much laid out the wiring diagram above.
 
The load from solar amps will largely dictate wire size, from what my installer told me. I have 4 200w 48v panels. 2 panels hooked in series times 2. Therefore 2 leads of 96v coming from the roof means a very low amperage that is coverted back to 12v via the 150/100 MPPT. I also have a smart shunt and a smart dongle. 810 amp hours of batteries.
 

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There are so many YouTube videos available that cover all these topics. I’d stick to looking it up there. I went with Victron a 24 volt system. It’s good to have a switch before the controller to disconnect the solar panels, ground and positive disconnect. Also, one on your battery positive before the linx distributor. We’ve been enjoying having the power! We’re Boondocking as I write this response. While you’re there, good time to install a surge protector. IMG_3709.jpegIMG_3712.jpeg
 

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In my opinion a fabulous resource is shop.explorist.life. I purchased most of my system through them and utilized their wiring diagrams to arrange my system.

Though my system is not as large as the OP’s system I had the same concerns about properly fusing the system and sizing the wiring to the solar panels and batteries. Their YouTube videos are fantastic - they just released one this week on placing fuses and circuit breakers properly.

The old adage that it’s too expensive (and time consuming) to do it twice fits solar systems on RV’s.

Keep us posted!

Bob
 
You say you are not doing the installation yourself but the questions are pretty specific, which the installer should be able to answer. Are you using an experience installer that will know the correct placement/sizing of fuses, cabling, cut off switches, etc.? Just want to make sure... Looks like you'll have a robust system.

One suggestion if you haven't already purchased the Multiplus...consider going 24V vs 12V. It would be more efficient if you plan on heavy loads. Though admittedly your system (and mine) are just on the cusp of where 24V starts to make more sense. Either way it will be fine, but if I had mine to do again, I would have gone 24V although 12V has not caused any issues after a couple of years of heavy use.
Yes they are experienced and I trust them. I am asking as I want to educate myself before I get this done.

Oldcow
 
There are so many YouTube videos available that cover all these topics. I’d stick to looking it up there. I went with Victron a 24 volt system. It’s good to have a switch before the controller to disconnect the solar panels, ground and positive disconnect. Also, one on your battery positive before the linx distributor. We’ve been enjoying having the power! We’re Boondocking as I write this response. While you’re there, good time to install a surge protector. View attachment 733388View attachment 733389
There are indeed many videos that I have watched. I still appreciate the opinions on this board. Nice looking set up. I do have a Hughes hardwired surge protector.

Oldcow
 
I have acquired most of what I need for my new system. I will not be doing the install, but I still like to understand the wiring.

I am most interested in where any shut off switches, bus bars and fuses should go. So far I am thinking shut off switches between the solar panels and the MPPT, buss bar (maybe Lynx Distributor Power in) between the 3 MPPT's and the batteries and between the batteries and the inverter. For the wiring, from the panels the MPPT I have read 10 gauge is fine. I have yet to really dig into the size for the rest.

What is the best way to connect the batteries? Series, parallel or both?

Here is what I have and what I will be installing;
2 Rich 200W panels in series to a MPPT 100/50
2 series of 4 195W panels down to 2 MPPT 150/60
3 LiTime 280 ah batteries
Victron Multiplus 3000 2 X 120 inverter
1 Victron smart shut

I would appreciate any simple wire diagram drawing to a similar type system just to get my head around it. And if one exist that I can change to my needs that would be awesome as well.

Oldcow
Have you checked out Explorist Life? Lots of info and wiring diagrams. They do installs and consultations for all types of RV. I spent 2 years of researching before adding solar to our 5th wheel and this site really came in handy for me. Home
 

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