After doing a night landing currency flight, I got a low voltage note from the JPI for 12.0 volts. I did some troubleshooting the next day and everything looks normal after start. Showing 14 volts on the bus and battery charging normal after start. I put on all the external lighting and as soon as I put on the big landing light I could watch the system voltage dropping about .1 volt every few seconds and the battery shows a slight discharge. I have a Hartzell 70 amp alternator, and the landing light is an older GE (halogen?). Data on line shows this could be up to a 250 watt light = over 20 amp draw.
I'll be doing a little more data gathering the next flight, also will tweak up the voltage on the Plane Power regulator.
Does any of this sound familiar, or is there a significant issue in there somewhere?
Attaching the JPI plot for volts showing exactly where the landing lights come on and off.