There are 2 MRJ2S-350A drivers both purchased as used, 1 HC-SFS352 AC servo Motor, and 1 HC-SFS352 with S logo at the encoder cap (this one purchased 2 days ago). From the picture posted at the beginning, the Motor is a HC-SFS352 (no S) connected to 1 of the MRJ2S-350A, when switched on the motor speed up fast + acceleration then stop as AL on the LED screen appeared AL 51, since it was purchased as used I have no idea what had been set previously so I restored back to factory setting by going to Parameter 182 ---> use up & down keys tilll it display 0012 then press "set"--> power off drive then power on drive. Now I know this drive is at deffault settings, usually from here onwards with all the cable connected correctly, CN1B (VR knob for speed control), CN2(Encoder), 3ph power from the main to Driver's L1 L2 L3, and U,V,W to AC Servo Motor's Power, I should be able to control the speed of the Motor via the VR having the Pr 0 (0002) and 1(0001) set correctly, but the Motor still doing what it used to, another strange behaviour was when CN1B is not connected tot he Drive, the motor still be able to spin which shouldn't be. The same thing happens to the other MRJ2S-350A Drive, so I think I have purchased 2 faulty drives, to proof this is faulty I unplugged CN1B (VR speed control knob) and plug it to another Mitsu drive MRJ2S-100A (This is a working Drive) to test it, as I turn the VR knob the motor increase or decrease speed, this is what a genuine Drive should do.
I used the same cable for all drives.