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Product Description
The Mitsubishi MR-J2-20A AC servo amplifier, designed for high-performance applications, delivers 200W of power for precise servo control. It accepts either single-phase 230V or three-phase 200-230V AC input at 50/60Hz. With a 0-360Hz frequency range and a constant 170V output, it ensures accurate motor control. Standard features include pre-wired I/O connectors for easy system integration, a built-in communication connector for network connectivity, and analog output for PC monitoring. A four-digit, seven-segment LED display provides at-a-glance operational information, and battery backup safeguards absolute position data. Despite its capabilities, the MR-J2-20A weighs only 0.7 kg, simplifying handling and setup.
Is Your Device Showing These Signs?
The Mitsubishi MR-J2-20A servo amplifier commonly experiences issues such as overcurrent faults stemming from shorted motor windings or IGBT failures. Drive instability and erratic motor behavior often result from resolver signal degradation or incorrect gain adjustments. Power supply capacitor degradation leads to undervoltage errors and operational failure. Communication errors arise from faulty RS-422/RS-485 interfaces or incorrect parameter settings. Overheating is a frequent problem, caused by inadequate cooling or a malfunctioning heatsink fan, triggering thermal overload protection.
Technical specifications
The Mitsubishi MR-J2-20A is a compact (0.7kg), 200W AC servo amplifier for high-performance applications. It accepts single/three-phase AC input (200-230V, 50/60Hz), outputs 170V, and features pre-wired I/O, communication connector, analog output, LED display, and battery backup.
Our Repair Process for the
MR-J2-20A
Our repair process for the Mitsubishi MR-J2-20A servo amplifier begins with a comprehensive diagnostic evaluation to pinpoint the root cause of the failure, focusing on common issues such as overcurrent faults, drive instability, power supply problems, communication errors, and overheating. We thoroughly inspect motor windings, IGBTs, resolver signals, capacitors, communication interfaces, and cooling systems. Defective components are replaced with high-quality parts, and the drive undergoes rigorous testing under simulated operating conditions to ensure optimal performance and reliability. Gain adjustments and parameter settings are meticulously calibrated to factory specifications. The repaired amplifier is then subjected to a final quality assurance check before being returned.
Your Guarantee: Warranty & Lifetime Support
Your satisfaction is our top priority, and we confidently stand behind the quality of our repairs. That's why every repair service is covered by our comprehensive 24-month warranty. Furthermore, we offer lifetime phone support – if you have questions or need assistance related to our repair down the road, we're here to help. Our service commitment is straightforward: we guarantee our work, and if you're not satisfied, we will make it right. Learn More about our Repair process.
Comprehensive Repairs You Can Depend On
We take immense pride in the quality and reliability of our work. Our process goes beyond simply fixing the immediate problem. We perform a comprehensive inspection of your main board (or other equipment) and proactively replace components known to be failure-prone or showing signs of potential future failure. Before any item is returned, it undergoes rigorous functional testing to ensure it meets performance specifications and operates flawlessly. Visit our main Repair Services page to learn more.
Save Significantly
Our primary goal is to save you hundreds, or even thousands, of dollars compared to the cost of new equipment replacement. By repairing existing components, we provide an economical solution that is also eco-friendly. At Roc Industrial, our commitment to integrity and community drives our consistent growth and ensures you receive a reliable, cost-effective solution.


Please Note: Roc Industrial operates as an independent service provider and is not an authorized distributor for the manufacturers or brands mentioned. Consequently, the original manufacturer's warranty is not applicable to items repaired or sold by us. Roc Industrial provides its own 2-year warranty on all repair services performed.
Buying Options
To receive a quote within 2 hours, please provide us with the details of your requirements. Our team will promptly review your request and send you a custom offer.
Ships from Rochester, NY