Servo Motor Wiring

Gents

I bought two Yaskawa servo motors from a Robot. They were
directly driving short ball screws on the arm and have
intergral tachs and encoders. The motors have 4 connections
that are unlabeled and there are 4 brushes on the motor.
How do I hook them up to test them? Any ideas on how
to identify the leads? I don't know if they are Permanent
magnet or have a field winding. How do I tell? Why
do they have 4 brushes instead of the normal 2? Resolution?

Any info appreciated

I'm Still in Singapore ... a "Fine" place to live.
( they have BIG fines for spitting, pissing,littering etc)
( cars here cost $40K US and up for a tiny 3cylinder box!!)
Going to visit some machinery dealers this weeked and see
what they have!! Plenty of them in the phone book.
To bad I cant get any of the heavy stuff home on the plane
as baggage!!!

dave