Mitsubishi Electric MR-J3-700B MELSERVO-J3 Servo Amplifier

Only 10 item(s) left in stock

Manufacturer: Mitsubishi Electric
Product No.: MR-J3-700B
Country of origin:United States
Product Type: Servo Amplifiers
Payment: T/T, Western Union
Weight: 500g
Shipping port: Xiamen
Warranty: 12 months

Description

Engineered for high-performance motion control, the Mitsubishi Electric MR-J3-700B is a digital, fully digital servo amplifier designed for seamless integration within the MELSERVO-J3 system architecture. Operating on a high-speed SSCNET III optical fiber bus interface, this 7.0 kW drive unit achieves highly synchronized multi-axis control with minimal electrical noise interference. The unit coordinates with high-resolution 18-bit absolute and incremental rotary encoders to provide exceptional velocity stability and positioning accuracy in demanding automation environments. Integrated real-time auto-tuning and advanced vibration suppression algorithms automatically adjust control loop gains to compensate for mechanical resonance, minimizing settling times on complex machinery.

Key Technical Features

SSCNET III Bus Connection: Fiber-optic communication interface enabling 0.44 ms cycle times and complete noise immunity over long physical runs.
Advanced Vibration Suppression: Dual-frequency adaptive vibration filters suppress both structural resonance and end-of-arm oscillation.
High-Resolution Feedback: Native decoding of 18-bit (262,144 pulses per revolution) absolute encoders for highly stable low-speed performance.
Adaptive Auto-Tuning: Continuous online inertia ratio calculation adjusts gain parameters dynamically during machine operation.
Compact Force-Cooled Chassis: Built-in cooling fan assembly optimizes heat dissipation for high-duty cycle heavy industrial applications.

Applications

Multi-Axis CNC Machining Centers: High-speed interpolation and synchronous path contouring.
Semiconductor & Electronics Assembly: Micro-positioning stages and high-throughput pick-and-place lines.
Automotive Press and Gantry Systems: Synchronized transfer systems requiring high torque output and rapid acceleration.
Packaging & Converting Machinery: Precision tension control, flying shears, and continuous rotary sealing axes.

Technical Specifications

Manufacturer	Mitsubishi Electric
Model Designation	MR-J3-700B
Series	MELSERVO-J3 Type B
Rated Output Power	7.0 kW
Output Rated Current	37.0 A
Output Rated Voltage	3-phase 170 V AC
Power Supply Input	3-phase 200 V AC to 230 V AC, 50/60 Hz
Control Interface	SSCNET III (High-Speed Serial Bus)
Speed Frequency Response	2100 Hz
Cooling System	Forced Air Cooling (Internal Fan)
Protection Rating	IP20 (Open Chassis)
Operating Temperature	0 to 55 degC (non-freezing)
Shipping Weight (Calculated)	7.2 kg

Interface and Power Connections

Terminal / Port	Connection Assignment & Function
L1 / L2 / L3	Main Power Supply Input (3-phase 200-230 V AC)
L11 / L21	Control Circuit Power Supply Input (Single-phase 200-230 V AC)
U / V / W	Servo Motor Power Output (Phase connection to motor windings)
CN1A / CN1B	SSCNET III Optical Fiber Connector (In / Out bus links)
CN2	Encoder Feedback Connector (High-speed absolute/incremental input)

Empirical Engineering Insights

Alternative Models & Compatibility

The MR-J3-700B can be integrated into existing SSCNET III lines but cannot directly share the same network loop with older SSCNET II or newer SSCNET III/H devices without using compatible gateway interfaces or configuring the master controller (e.g., Q-Series Motion CPU) for legacy mode compatibility. If retrofitting to MR-J4 series hardware, use the MR-J4-700B-RJ amplifier running in J3 compatibility mode.

Application Pitfalls & Engineering Notes

Given its 7.0 kW power output, this amplifier generates considerable heat during continuous deceleration profiles. If the internal regenerative braking resistor capacity is exceeded, the unit will trip with AL.30 (Regenerative Error). For high-inertia operations, installing an external regenerative option (such as the MR-RB5E or MR-RB137) is highly recommended. Always verify the cooling clearance: a minimum of 40 mm spacing is mandatory on both sides of the drive enclosure to avoid localized thermal pocketing.

Commissioning & Wiring Tips

Pay strict attention to the SSCNET III optical fiber cables (MR-J3BUS). They are highly sensitive to physical stress. Maintain a minimum bend radius of 25 mm. Sharp kinks or pinching will attenuate the light signal, leading to intermittent AL.37 (Parameter Error / Communication Error) faults that are notoriously difficult to diagnose in field environments.

Installation Guidelines

CRITICAL WARNING: HIGH VOLTAGE RISK

Ensure main and control power supplies are completely disconnected and locked out before initiating wiring. Wait at least 20 minutes after de-energizing to allow internal high-capacity bus capacitors to discharge. Verify the DC bus voltage across terminals P+ and N- is below 20 V using a verified voltmeter before touching any electrical terminals.

Mount the unit vertically onto a flat, metal panel plate. Ensure clean, conductive grounding contact through the mounting chassis screws to the backplane.

Wire the power inputs: connect L1/L2/L3 to the main 3-phase line, and L11/L21 to the separate control supply. Install a molded case circuit breaker (MCCB) and an electromagnetic contactor (MC) for system safety.

Connect the motor output lines (U, V, W) directly to the servo motor power terminals. Never wire utility AC mains directly to U/V/W as this instantly destroys the internal IGBT output module.

Insert the CN2 encoder connector until the locking tabs snap firmly into place. Connect the SSCNET III optical fiber cables to CN1A (and CN1B if in a daisy chain configuration). Keep optical dust covers on all unused ports.

Key Features:

#MELSERVO-J3 #Servo Amplifiers

What is the primary difference between the MR-J3-700B and MR-J3-700A?

The MR-J3-700B features an SSCNET III fiber-optic communication interface for digital motion network control. The MR-J3-700A uses an analog and pulse-train interface for point-to-point and traditional signal-based control layouts.

What causes the AL.30 error on the MR-J3-700B, and how is it resolved?

An AL.30 fault indicates a Regenerative Error. It occurs when regenerative energy returned from the motor exceeds the power dissipation limit of the built-in resistor. To resolve this, install an external regenerative resistor option (like MR-RB5E or MR-RB137) and adjust parameter Pr. PA02.

Can I use an optical cable longer than 20 meters with this drive?

Yes, standard SSCNET III fiber optic cables (such as the MR-J3BUS line) support runs up to 20 meters. For distances between 20 meters and 50 meters, special long-distance plastic optical fiber (POF) cables or glass fiber optic cables must be sourced to prevent transmission loss.

How long should I wait before servicing the wiring on a de-energized drive?

You must wait at least 20 minutes after switching off the primary power. The high-capacity internal DC bus capacitors store high voltage (over 300 V DC) and require this time to safely discharge through internal bleed circuits. Always measure DC bus terminals P+ and N- before servicing.

Global Express Shipping

Standard Delivery: 4-6 Business Days via DHL, FedEx, and UPS.
Express Dispatch: Same-day dispatch for in-stock orders placed before 2:00 PM (GMT+8).
Worldwide Coverage: Serving over 150 countries, including rapid delivery to Saudi Arabia and UAE.

Returns & Warranty

30-Day Guarantee: Returns accepted for in-stock products in original, factory-sealed packaging.
12-Month Warranty: Every industrial component is backed by our professional technical warranty.

Orders are processed and delivered Monday-Friday (excluding public holidays).

For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .

TECHNICAL SPECIFICATIONS

Country of origin

Technical knowledge

Electric Actuators Designed to Replace Fluids: Hands-on Tutorial

Electric Actuators Designed to Replace Fluid Power Systems: A Practical Industrial Automation Guide

This article explains how integrated electric actuators, such as SMC’s e-Actuator series, are transforming industrial motion control by replacing traditional pneumatic and hydraulic systems. It...

June 23, 2026

$Math Operations Using OpenPLC for Industrial Automation Applications$

Mitsubishi Electric MR-J3-700B MELSERVO-J3 Servo Amplifier