What we're seeing is the battery voltage rapidly increasing from about 14.4V to 14.8V. It isn't a spike. Spikes are usually generated when inductive loads are turned off. In our case, the battery is not capable of taking the charge, resulting in rapid rise in voltage, or voltage surge. Given the battery capacity, there's too much solar.
You can verify this assessment by disconnecting 2 of the panels. Battery voltage will now rise at a slower rate.
It seems like the big inverter looses it at 14.4V, not at 14.8V. You can verify this by connecting an ac light to inverter. When does the light turn off, at 14.4V or at 14.8V?
Sal
smkettner wrote:
I have never seen any spike with my MS MPPT as loads are removed.
