Alternator Charging Issue: Delco used on sailboat

[charlesmoore03]

I have a sailboat with a Yanmar 30hp Diesel.  The problem is that quite often the Battery Monitor Panel shows that the alternator is not charging.  Some minutes later it mysteriously starts charging.  My normal RPM is 550 to about 1800 and I do not take it to 1800 until unit is well warm.  I am not sure what the pulley rations are but I would guess 3:1 but I can measure next time at the boat.  I also have a spare that has checked good.

The unit is wired such that the big red wire goes to the start battery, via a Combiner, and another smaller wire coming from a black flush oval terminal block is directly connected to the big red wire.  I do not know if it is the field or sense wire (or any one of the other ones under the oval terminal).  

How do I determine if this unit has a "one wire" regulator or the "standard" regulator?  What happens if the sense wire and BAT are tied together using a "standard" regulator?  What Happens when "one wire" regulator sense wire is tied to BAT?