Jump to content

Solar system install


L.R.S.
 Share

Recommended Posts

On 5/28/2021 at 4:42 PM, wopachop said:

If socal sees this or if anyone knows, i would be curious as to why choose parallel? 

In residential/commercial, we wire series up to 480VDC so we can get away with #10 THWN-2, parallel would work fine but would need much bigger wire.  On an RV with optimizers and 2 modules, I dont see why one would be better than the other.  

Link to comment
Share on other sites

On 5/28/2021 at 4:42 PM, wopachop said:

If socal sees this or if anyone knows, i would be curious as to why choose parallel? 

I don't have the time to explain Ohms Law so I will just leave this

One you keep the voltage the same one you keep the amperage the same.

Now go use google and come back and explain to the rest of us.

  • Haha 1
Link to comment
Share on other sites

It's simple. Trailers are much more prone to shading, either from trees or A/Cs and vents on the roof. If you're in parallel and 1 solar panel gets partially shaded, you only lose power from the one panel. If they're connected in series, you'll lose power from the whole string. It's better to get 2/3 or 1/2 power than none at all.

Link to comment
Share on other sites

Little bit of info i learned recently was that a PWM controller matched with 12v batteries requires 12v panels in parallel. That would be an example where the series configuration would not work. (from a video i watched, please correct if thats wrong) 

Link to comment
Share on other sites

  • Forum Moderator
Posted (edited)
On 5/28/2021 at 4:42 PM, wopachop said:

If socal sees this or if anyone knows, i would be curious as to why choose parallel? 

You would double your voltage to panels. I bet the controller won't handle the higher voltage. Big home panels are 36 or 48 volts.  Btw those panels are 60 bucks all over facebook. Also I would use the best mppt controller you can get.  Mine was about 650. 

Edited by Squatcher
Link to comment
Share on other sites

Im sure LRS got great advice. I was just surprised the 2 panels were in parallel. I have been wanting to add a 2nd panel for years, and was convinced they would be configured in series. Did a little reading/watching and think these 2 statements are true? 

1. MPPT controllers can benefit from 2 panels configured in series. (to keep it simple just using 2 panels)

2. PWM controllers feeding a 12v battery bank require all 12v panels to be in parallel even if the controller says it can handle 24v. 

I dont fully understand what r3meyer was saying about shading. It must have to do with efficiency but i wonder if the type and quality of solar controller also comes into play. Take 2 equal setups with 2 panels each. One setup in parallel and the other in series. You are parked near a tree and 1 of the panels goes into shade. Apparently the 12v parallel setup can produce more amps under that condition? 

I feel like thats a rare condition for us boon dockers. Youre out camping and a cloud comes over. All the panels are equally shaded. If youre parked near a tree, at a local campground, good chance youre on full hookups. 

Link to comment
Share on other sites

  • 3 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

Shout Box

Shout Box

You don't have permission to chat.
    ×
    ×
    • Create New...

    Important Information

    Terms of Use Privacy Policy