Calling on Solar Techies
I have been thinking of going solar for some time and decided to pull the plug. My wants are a 400 to 500 watt system. I have four 12 volt batteries with 340ah. I am not planning on changing b...
Forum Discussion
1L243 wrote:
I like the Bluetooth aspect of the Kinverch inverter I can live with that.
While were at it can we talk MPPT VS PWM Controller
The system I am looking at is only up-gradable to 500 watts with a 40a PWM controller. From what I have read the PWM controller is preferred to smaller systems and the MPPT is preferred for the larger systems?
Any thoughts.
For what you are planning, IMO you will not need more than that 400w flat on the roof. Very like what we do, so should work about the same.
Doesn't matter much whether it is PWM or MPPT for amps to the battery. The weather is so variable, you just take what Mother Nature offers that day; you won't notice whether you could have got a few more AH with MPPT on any particular day. Keep the gen handy the way the weatherman lies about his so-called forecasts!
I have used both PWM and MPPT and posted lots of numbers over the years for what I got at various times including PWM vs MPPT. Not going to repeat all that info again here. Comes down to not much diff with 12v panels, and you must have MPPT with 24v panels so the buck converter can bring it down to 12v. ( PWM is only 12-12 or 24-24---no buck converter)
You should toss those 12v batts for the four 6s, but can get by this summer with solar with the 12s if out in the open. Before camping in the woods next Fall, IMO have the 6s.
In the longer run, don't forget you can add solar if needed by having the new solar with its own controller and just put both controllers on the same battery bank set to the same voltage so they add their amps ok.
EG, I saved solar from previous RVs and crammed it all onto this Class C, so it was three controllers--two MPPT and one PWM. I have since moved one set to the TC (255w single panel and a 20 amp MPPT Tracer) So now in the C there is a 275w panel with a 20 amp Eco-Worthy MPPT and three 12v 100w panels with a 30 amp PWM for 575w total. It is more solar than we really need in the summer so your 400 ought to be enough since you indicate you will use fewer AH per day than we usually do.
