Thanks for straightening me out.
I stand corrected. I got bad information from the Sterling regulator installation
manual, page 5 on http://www.sterling-power-usa.com/li...structions.pdf
It seems the vast majority of alternators are negative field control, and Balmar
is one of the few (only?) manufacturers clinging to positive field control. I like the features on their regulator, but I'm a little chagrined that they don't accommodate neg field alternators.
Oh well. At least I was able to convert my alt to use the Balmar
reg, and I can switch it back if I ever need to dump the Balmar.