Mitsubishi Electric MELSERVO-J4 Series Transition Handbook page 286

Part 6: Review on Replacement of MR-J3-_T_(DIO command/ Serial communication operation) with MR-J4-_A_-RJ
(a) For replacement of servo amplifier
Allows the J3 series servo motors to drive in MR-J4-_A_-RJ. Refer to "Part 7: Common Reference
Material" for target motors.
DIO command
Controller
HF-_P/HC-_P/HA-_P motor
(b) For replacement of servo motor
MR-J3-_T_(DIO command/Serial communication operation) cannot drive an HG motor. When the
servo motor is replaced withan HG motor, simultaneous replacement with MR-J4-_A_-RJ and an
HG motor isnecessary.
MR-J4-_A_-RJ and MR-D01
6 - 7
Serial communication operation
Controller
MR-J4-_A_-RJ
HF-_P/HC-_P/HA-_P motor
RS-422
communication