Salvo wrote:
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...
As shown in the first video clip, the big inverter runs fine at 14.4V and loses it when the voltage rise approaches 14.8V. It is only during the rapid voltage rise that happens when the solar charging status is at its max voltage (14.4V in this case) that the inverter faults. The same rapid voltage rise occurs when I'm not already at the max charging voltage, but that is no problem because all voltage movement occurs well below the inverter's high voltage disconnect. I only have 2 panels and I can't easily switch one off. But your description of the issue occurring sounds right on the money based on what I observe.
The big inverter seems to do fine as clouds come and go (affecting the available charging current). It is only during the load drop situation (or sometimes just flipping the inverter on) when I'm charging right at 14.4V that I get the high voltage disconnect from the inverter.
