BenMoz.... No problem.
I can't give you a ton of information about the motor/encoder combination right this second, but I am 95% sure I recognize both of these units from my M3 investigations. If that is correct, then the specs for them are in the one of the documentation books for the MR-S11. This is both good and bad. It is good because you can find specs. Among this you will be able to get the pinouts for the encoders. There are two track for them, the position tracks and the UVW sequencing tracks. Now the bad.... The M3 is an older design than the MDS you have. I don't know what they changed on the motor side... You'd have to compare the docs between the MR-S11 and MDS to see if you can find a parallel. The bad thing about Mitsubishi is that it is a very "closed" system. On the M3 control, you cannot free-form motor information. Instead, you have to provide an ID that basically sets the control to the motor. Yes, there are other things you can do for tuning, but I find it highly suspicious when I need to put 13 in for an HA123, for instance (completely made up numbers there...) because I have no idea what is happening with the "13" is being used for..... The point here is that if the MDS is using the same motor/encoder setup, then you are in good shape.... Otherwise, you might need to do a bit more poking around.
I'll send you a PM in a bit..... Well scratch that.... Apparently you don't have your account setup so that it accepts PMs.