Mitsubishi MR-J2/J2S to MR-J4 Servo Migration Kits
Upgrade Legacy Servo Systems with Pre-Packaged Migration Kits
Many facilities still rely on Mitsubishi MR-J2 or MR-J2S servo systems to keep critical equipment running. However, as these legacy systems continue to age, replacement parts can become more difficult to source. As a result, relying on used or refurbished components may increase the risk of unreliable repairs, unexpected downtime, and costly production interruptions.
To help address these challenges, Kim Controls helps simplify the move to MR-J4 technology with Pre-Packaged Migration Kits for A-Type and B-Type amplifier applications. In addition, these kits are designed to make the upgrade process easier, reduce installation challenges, and support a smoother transition with less disruption to production.
With the right migration kit, you can:
- Reuse existing wiring with conversion cables that help reduce rerouting and rewiring
- Simplify installation with drop-in mounting compatibility
- Support accurate parameter conversion to help maintain system performance
- Plan ahead for aging servo equipment and reduce the risk of unplanned downtime
- Get support from Kim Controls for kit selection, upgrade planning, startup, and troubleshooting
Simplify MR-J2/J2S to MR-J4 Upgrades with Complete Migration Kits
Kim Controls helps make MR-J2/J2S to MR-J4 upgrades easier to plan with Mitsubishi Servo Migration Kits built for active production environments. In addition, each kit includes the components needed to simplify the migration, including pre-packaged hardware, exact-fit amplifier options, conversion cables, and flexible motor planning.
As a result, these kits help reduce wiring changes, shorten installation time, and support accurate parameter setup. This makes it easier to modernize aging servo systems while reducing guesswork, downtime risk, and production interruptions.
Pre-Packaged Convenience
Each kit includes the key components needed for your upgrade, including the amplifier, conversion cables, and motor when required. This helps simplify ordering with one part number and makes inventory planning easier.
Conversion Cables Included
Included conversion cables let you keep existing wiring in place. This helps reduce rerouting, rewiring, installation time, and potential wiring errors during the upgrade.
Exact Fit & Mounting Compatibility
MR-J4 amplifiers are designed to match the mounting patterns of existing MR-J2/J2S units. This supports a drop-in replacement that helps simplify installation and minimize downtime.
Expert Support
Kim Controls provides guidance for parameter conversion, startup, and troubleshooting to help support a smoother migration. Most support is available at no cost during normal business hours within our APR region.
Fast, Reliable Upgrades
Pre-configured kits and parameter conversion tools help make the move from MR-J2/J2S to MR-J4 faster and more efficient, reducing production interruptions during the upgrade.
Flexible Motor & Amplifier Options
Amplifiers can be replaced separately from the motor, giving you flexibility for staged upgrades or backup kit planning. If a motor needs to be replaced, the corresponding amplifier must also be replaced to maintain proper operation and system performance.
Our Servo Migration Kits: All-In-One Solutions
A-Type Amplifier Kit: MR-J4-A
- Servo Amplifier
- Encoder Conversion Cable
- I/O Conversion Cable (I/O cable require external 24VDC)
- Monitor Conversion Cable

Use Your Existing Wiring
The MR-J4-A kit allows you to keep current MR-J2/J2S wiring in place without rerouting or rewiring. This helps reduce installation time, limit wiring errors, and minimize production downtime.
Parameter Conversion for Fast Startup
MR-J2/J2S to MR-J4 parameter conversion is included to help ensure your servo system operates correctly after the upgrade. Pre-configured settings preserve motion profiles and operating parameters, making the transition fast, reliable, and efficient.
Same Size and Mounting Compatibility
MR-J4-A amplifiers match the size and mounting patterns of existing MR-J2/J2S units. This drop-in compatibility helps simplify installation, avoid cabinet modifications, and reduce downtime for industrial automation systems.
- Upload parameters from old amplifier
- Replace old amplifier with new amplifier in the cabinet
- Connect existing cables to new conversion cables
- Download converted parameters to new amplifier
- Power up amplifier
- Ready for operation
- Upload parameters from old servo amplifier
- Convert parameters (Full detail instructions will be provided)
- Disconnect existing cables from old servo amplifier and remove amplifier from cabinet (Make sure existing cables are labeled appropriately (they will be reconnected to new amplifier)
- Mount MR-J4 amplifier in the cabinet (MR-J4 amplifiers have the same dimensions for mounting)
- Connect IO, Encoder, and Monitor conversion cables to the MR-J4-A amplifier
- Connect existing cables to their respective conversion cables
- (If using on-board IO) – Connect 24VDC to the 2-pin (red/white) breakout connector on IO conversion cable
- Power up new MR-J4-A amplifier
- Download the converted parameters to the new MR-J4-A amplifier
- Cycle power on MR-J4-A amplifier
- Home servo amplifier
- Ready to begin normal operation
B-Type Amplifier Kit: MR-J4-B
- Servo Amplifier
- Encoder Conversion Cable
- I/O Conversion Cable (I/O cable require external 24VDC)
- Network Conversion Module

No Program Changes Required
The MR-J4-B amplifier is pre-configured in MR-J2S compatibility mode, eliminating the need for programming adjustments and allowing the system to operate immediately after installation.
Pre-Configured for MR-J2S Compatibility
Designed to match MR-J2S parameters, the B-Type kit supports a seamless transition to MR-J4 technology without changing existing motion profiles, safety limits, or operating settings.
Quick Swap with Minimal Downtime
A drop-in design and included conversion modules help make amplifier replacement fast and efficient, reducing installation time, minimizing downtime, and keeping production moving.
- Attach SSCNET adapter module to the side of the new amplifier
- Replace old amplifier with new amplifier in the cabinet
- Connect existing cables to new conversion cables
- Power up amplifier
- Ready for operation
- Disconnect existing cables from old servo amplifier and remove amplifier from cabinet (Make sure existing cables are labeled appropriately [they will be reconnected to new amplifier])
- Attach the SSCNET adapter module to the side of the MR-J4-B amplifier (The male socket on the side of the SSCNET module connects to the female socket on the side of the amplifier)
- Mount MR-J4-B amplifier in the cabinet (MR-J4-B amplifiers + adapter module have the same dimensions for mounting )
- Connect IO, Encoder, and Monitor conversion cables to the MR-J4-B amplifier (if using)
- Connect existing cables to their respective conversion cables
- (If using on-board IO) – Connect 24VDC to the 2-pin (red/white) breakout connector on IO conversion cable
- Power up new MR-J4-B amplifier
- Home servo amplifier
- Ready to begin normal operation
Technical Considerations for Migration Kits
- Flexible Upgrades: Replace the amplifier independently of your existing motor, allowing staged upgrades or backup kits.
- Motor Replacement Requirement: You cannot replace a motor without also replacing the amplifier due to the higher encoder resolution of MR‑J4 motors.
- Compatibility Assurance: Older MR‑J2/J2S amplifiers cannot process the MR‑J4 motor’s feedback; this ensures your system operates reliably.
- Minimized Downtime: Separate kits let you plan upgrades efficiently while keeping production running smoothly.
- What It Does: MR‑Configurator2 software converts your old MR‑J2/J2S amplifier parameters to the new MR‑J4 format, ensuring your servo system operates correctly after the upgrade.
- No License? No Problem: If you don’t have MR‑Configurator2, you can send us your existing parameter file, and our team will perform the conversion for you.
- Why It Matters: Proper parameter conversion preserves your system’s motion profiles, safety limits, and operational settings, avoiding unexpected downtime or errors.
- Ease and Confidence: Whether you convert parameters in-house or through Butler & Land, the process is streamlined so your MR‑J4 upgrade is smooth and reliable.
- Advanced Control Modes: CP and CL series amplifiers include specialized positioning methods, such as point tables and other modes that are not automatically converted to MR‑J4.
- Manual Entry May Be Required: Certain settings may need to be manually configured on the new MR‑J4 amplifier to preserve your system’s motion profiles.
- Our Guidance: Butler & Land will gather information about your CP/CL units to determine the exact software steps needed, ensuring a smooth upgrade.
- Why It Matters: Proper handling of CP/CL models avoids unexpected behavior, maintains precision, and minimizes downtime during your migration.
Check Your MR-J2S Models and Plan Your Upgrade
Confirm your current servo system before planning the move to MR-J4 technology. To make this easier, the complete MR-J2S Motors and Amplifiers list includes compatible models across A, B, CP, and CL series. With this information, you can identify your units, plan the right migration path, and order the correct kit.
Then, download the list to simplify upgrade planning, reduce guesswork, and support a faster, more confident servo migration with less downtime.
Get Clear Answers Before You Upgrade
Kim Controls can support Mitsubishi MR-J2 and MR-J2S servo migrations across A, B, CP, and CL series. A-Type and B-Type applications are the most common, while CP and CL models may require additional review because of advanced positioning methods or specialized settings.
In many cases, yes. Amplifiers can often be replaced while keeping the existing motor in place, which can support phased upgrades or backup kit planning. However, if the motor is being replaced, the matching amplifier must also be replaced because MR-J4 motors use higher encoder resolution.
No. Mitsubishi Servo Migration Kits include conversion cables that allow you to keep existing wiring in place. This helps reduce rerouting, rewiring, installation time, and potential wiring errors during the upgrade.
Yes. MR-J4 amplifiers are designed to match the size and mounting patterns of existing MR-J2/J2S units. This drop-in compatibility helps simplify installation, avoid cabinet modifications, and reduce downtime.
For A-Type migrations, MR-Configurator2 software converts existing MR-J2/J2S amplifier parameters into the MR-J4 format. If you do not have MR-Configurator2, you can send Kim Controls your parameter file and our team can complete the conversion for you. For B-Type migrations, the MR-J4-B amplifier comes pre-configured in MR-J2S compatibility mode.
Kim Controls can help with kit selection, parameter conversion, startup guidance, and troubleshooting. Our team can review your current setup, identify the correct migration kit, and support the technical details needed for a smoother upgrade.
Yes. Migration kits can be ordered for planned upgrades, critical machines, or backup inventory. Because each kit is packaged under a single part number, it is easier to simplify ordering, support spare parts planning, and prepare for aging servo system failures.
Start by identifying your current MR-J2 or MR-J2S amplifier and motor models. Kim Controls can review your equipment information and help match your system to the correct MR-J4 migration kit for your application.
