Solar Install Need info

[SCvanman]

Ok, here is the setup I am looking at doing and I need some questions answered.

I have a hi-top (bubble top) E150
#1
I plan on putting 2x 100w flexible panels on the roof.
 I will run an inline 15a MC4 fuse from + to a buss board in van cabinet
 The negative will connect to a - buss board

#2
 I will also have 2x 100w portable panels that I can setup outside when needed.
 This will also be fused at the solar panels inline.
 These will plug into side of van via 50' ext. cord
 I will run + to same + buss board and - to same - buss board.

From the buss board I will run to mppt controller.

These are my questions. So do I run the roof panels in series and the portable in parallel?
Can these to be attached to the same buss terminal and than fed to charge controller?
Will I need a special charge controller for this setup or should a 40a CC work?
Any precautions I should take with this setup?

 

[John61CT]

Victron BlueSolar MPPT @ 100/30  will let you go either way with both.

To get max output from MPPT you probably want to serial at least 2x nominal 12V, doubling actual voltage on that string to say 30-40.

And that allows you to go longer wiring at less cost and weight.

Make sure all the panels per controller have at least matching voltage.

Or get 2x the 75/15 version, around the same cost, dedicate one controller to each type of panel.

 

[GotSmart]

For the portables.  What I ended up doing was putting in electric cord ends on the panels, and connected them with a power strip.  Just clearly mark everything SOLAR 12 Volt.  

Precautions?   Check everything twice.

 

[Trebor English]

A 100 watt panel, or two in series, have a maximum current of 5 or 6 amps.  Your extension cord ought to be #10 but even if you use 14, the current capacity is 15 amps.  The panel doesn't have the current capacity to overload the wire.  You don't need a fuse between the panel and the charge controller.  That would add more resistance to the circuit.  

The extension cord likely has 3 conductors.  The normal 120 volt use are hot, neutral, and safety ground.  You can use 2 conductors for one, plus or minus, and just one conductor for the other.  Whichever lead has 2 conductors in parallel has half the resistance so the total round trip resistance is less.

If, on the other hand, you only use two conductors, pick neutral and safety ground for plus and minus.  If you use regular plugs and sockets and your panel gets a regular 120 volt appliance plugged into it, nothing happens.  If your solar controller input gets plugged into a live 120 volt socket then your controller gets neutral, almost zero, and safety ground, zero, for inputs.  Likely nothing bad happens.  Similar logic applies using 3 conductors.  Use hot and neutral together for plus.  An appliance will get DC plus on both AC inputs and DC minus to safety ground.  No problem.  If the charge controller gets plugged into a live 120 volt socket the hot to neutral short will trip the breaker not fry the van.  This way you can use a regular extension cord for solar or for shore power if that is an option.  

To be nice and not trip the 120 volt breaker you could put a 15 amp 120 volt fuse in the hot lead input to the charge controller.  Not a 32 volt automotive fuse but rather a 120 volt fuse.

 

[SCvanman]

GotSmart
Yes I was looking at doing the same. I actually have a 30a chord from my old rv days that I may re-wire for standard plugs.
John61CT
Thanks, So if I am understanding this correctly, I should do both sets wired in series? That would put it at about 80 VoC which that 100/30 would work perfectly for right?

 

[SCvanman]

Thanks for the info. I was mainly using the inline fuses at the panel ends to have a way of shutting off power from solar for any maintenance in the electrical panel end. I had read somewhere here that it is a pretty simple and easy way to do this. I am glad to hear the wire can handle anything the 2 100w panels can produce though.

 

[John61CT]

Thanks, So if I am understanding this correctly, I should do both sets wired in series? That would put it at about 80 VoC which that 100/30 would work perfectly for right?

If each panel is rated max 20V, then all four in one series string is 80V, @ say 5A.

If 2S2P two strings 40V each, 10A total.

If all four paralleled 20V 20A.

The controller can handle any of those setups.

2S2P likely "best" for what you're talking about, if all four panels match.