The field coils are all wired in series. I checked the polarity of the field coils while the armature was removed with a compass and they alternate north, south, north, south, north, south.
All 6 field coils are identical. 1500 turns #19 wire. It definitely does not have any interpoles. I took photos of the armature but not the fields while it was disassembled.
I checked the armature for shorts and opens by placing a growler on the armature and then measuring the voltage between commutator bars. I'm sure both armatures are ok.
No, there aren't any interpoles.
I bench tested a 50 year old Robbins & Myers 250 rpm, 400 pound, 3000 watt, 120 vdc generator with a 188 segment commutator. These generators have 4 brushes. Three of the brushes, as originally equipped, are a soft carbon/graphite composition and the fourth brush, originally installed in the...
