Old Dannish Self Regulating generator

[RonnieBe]

Hi, I bought this old generator a few months back.

Now I'm thinking of powering it up, but I'm not sure what I'm missing.
Motor is a old JLO two stroke engine.

Data:
Type ST 2, 4
3-phase, 380V, 7.5kVA

The Neutral and the 3-phases are easy to locate, but then there is also two thinner wires S and T, and I don't know what they are for and what should be connected there.
The generator is self regulating so no external AVR is used.

Any one who knows how to wire this up?

[joestue]

my guess would be the battery charging output.

is this a self regulating diode+capacitor mounted on the rotor? Or is it self regulating via saturation: basically just a coil on the rotor, two slip rings, a full wave rectifier, and a coil in the stator feeding the rectifier.