I have been reading about controllers...
Spent some time
here
Everyone seems to have opinions as to which controller is best.
I am considering a Morningstar TS-60 Tristar-60 Amp. Victron seems tried and true so I am still torn.
What would be the advantages and disadvantage of splitting the panels?
So - using my comments about wire size in the prior post:
Option a)
- Run the panels in series
- Buy a controller designed for 600 watts or so.
- In a perfect world, perhaps a controller with a bit more headroom - even 800 watts
- Use 10 awg PV wire down to the controller, since the currents are ~ 10 amps
- Controller to battery wire has has to be able to handle 600 + watts @ 12 volts ~ 50 - 60 amps
If your plans are pacific north west, ,then perhaps count on 1/2 of this much power.
If your plans are New Mexico high plains, then power performance can be substantial.
The controller needs start to push something pretty large - like a midnight solar classic or another large controller like the ones that you mentioned.
- This is probably the most efficient solar to battery charging approach when things are perfect.
- It is also good for poor light conditions because it will usually create at least some power even in dismal light
- It is the most susceptible to failing completely from a single point failure mode. (panel breaks, controller goes down, fuse, etc)
Option B)
- Run the panels in parallel
- AFAIK, if you do it this way, the panels are all supposed to be wired to a combiner box on the van roof, and then a large wire down to the controller
- Kind of an expensive approach, but simple
- With 600 watts of panels on the roof - my guess is that it is pretty full up there already and adding a combiner box might be painful
- There won't be all that much voltage headroom by the time you get to the controller, so it really forces a PWM controller path. Possibly multiple in parallel.
- More wire required
- Resistant to a single panel failure
- Requires several large wires
- Efficiency will vary depending on location
Option c)
Break it into 2 independent arrays
- For example, 2P in each array, or 2S in each array - whatever you think is right for you
- Solar controller for each array
- Now you can use 10 awg wire all the way through from the panels - controller - bus bar.
- Complete redundancy and identical spare parts. If needed, you can borrow parts from one array to keep the other operational in the middle of nowhere.
In all approaches there are benefits and limitations. Any of these approaches can work.
