Steve_S
Offgrid Cabineer, N.E. Ontario, Canada
Well, let me put it this way. I initially though 12V/20A would be ok, and got a small buck converter which runs from my 24V bank, but one heavy solar charge day and the voltage literally melted the innards and allowed the full 24V to go through it... fortunately not much was active on the 12V side BUT it damned near fried my RV furnace (which uses 12V) Now 20A amp may also seem like a lot but in 12V world it really isn't. A Better & more powerful stepdown is wise to provide good reliable power with enough kick behind it. As well EVEN MORE IMPORTANTLY, the better units can take in up to 30-VDC and some a little higher with failure. One must account for the voltages these will see when batteries are being charged.