Mitsubishi Electric MELSERVO-J4 Series Transition Handbook page 154

Part 4: Replacement of MR-J3W-_B with MR-J4W2-_B
(4) Separate repair
(a) Replacement of servo amplifier
Replacing the system, you can drive some J3 series servo motors with MR-J4W2-_B (J4 mode) and
MR-J4W2-_B(J3 compatibility mode). Refer to "Part 7 Common Reference Material" for the
applicable motor.
SSCNETIII
servo system
controller
(b) Replacement of servo motor
The J4 series servo motors cannot be driven by MR-J3W-_B. Replace the existing servo amplifiers
and servo motors with MR-J4W2-_B servo amplifiers (J3 compatibility mode) and J4 series servo
motors simultaneously.
SSCNETIII
servo system
controller
MR-J3W-_B
J3 series
servo motor
MR-J3W-_B
J3 series
servo motor
MR-J4W2-_B
(J3 compatibility mode)
J4 series
servo motor
MR-J4W2-_B
(J3 compatibility mode)
J4 series
servo motor
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