MITSUBISHI MR-J3-700A MELSERVO-J3 Servo Amplifier

Overview

The MITSUBISHI MR-J3-700A is a 7kW general-purpose pulse-input servo amplifier from Mitsubishi MELSERVO-J3 series. The MITSUBISHI MR-J3-700A accepts pulse train command signals from upper controllers such as PLC and CNC, supporting position, speed and torque closed-loop control for matched Mitsubishi AC servo motors. It reads serial encoder feedback signals and outputs high-precision PWM power to drive the motor, and supports regenerative braking with optional external regeneration resistors. The MITSUBISHI MR-J3-700A is a widely used legacy spare unit for machine tools, packaging equipment and automation production lines.

Features

The MITSUBISHI MR-J3-700A operates on three-phase 200V to 240V AC power supply, with 37A continuous output current and 111A peak output current. It supports differential pulse input up to 4Mpps, and incremental or 17-bit absolute serial encoder feedback. The MITSUBISHI MR-J3-700A integrates comprehensive protection functions including overcurrent, overvoltage, undervoltage, overheat, encoder error and overload alarm. It uses USB and RS422 communication interfaces for parameter setup, monitoring and fault diagnosis via MR Configurator2 software. The MITSUBISHI MR-J3-700A adopts standard cabinet vertical installation and original pin definition for direct replacement.

Specs

Device Type: MELSERVO-J3 servo amplifier Model: MITSUBISHI MR-J3-700A Rated Power: 7.0 kW Input Power: 3 × 200V AC to 240V AC, 50/60 Hz Continuous Output Current: 37 A Peak Output Current: 111 A Command Input: Pulse train input (differential / open collector) Feedback: Serial encoder interface Software: MR Configurator2 Mounting: Vertical installation inside control cabinet Protection Grade: IP00 Application: CNC machine tool, packaging machine, material handling, high dynamic positioning axis

Principle

The MITSUBISHI MR-J3-700A receives pulse or analog command signals from the host controller. The internal control board compares the command value with rotor position and speed data fed back by the motor encoder, then adjusts the PWM signal of the IGBT power module to realize closed-loop motion control. During motor deceleration, regenerative energy can be consumed by external brake resistance. The MITSUBISHI MR-J3-700A continuously samples current, voltage and temperature signals. When a fault condition is detected, it cuts off power output, locks the servo and stores fault codes for troubleshooting.

Applications

The MITSUBISHI MR-J3-700A is used for heavy-duty servo axis driving in CNC lathes, machining centers and automation assembly lines. It serves high-speed positioning and constant torque control for large packaging and converting machinery. The MITSUBISHI MR-J3-700A applies to spare stock and emergency repair of existing MELSERVO-J3 motion control cabinets. It also supports servo axis renovation and parameter tuning projects of old Mitsubishi servo systems.