Precision Zone Expertly Repairs Drives-AC Servo Mitsubishi MR-S2

Here at Precision Zone, one of our specialties is the repair services of Mitsubishi servo units. One series that we often work on is the MR-S2 servo series.

Mitsubishi's MR-S2 is a series of 2-axis integrated AC servo amplifiers. There are 6 different offerings of capacities ranging from 0.2kW up to 2.0kW. These units have digital control that had replaced the analog circuitry of past series which now provides better response repeatability and reliability. This also leads to a reduction in parts and components which reduces the possibility of failure and increases reliability.

When assessing the functionality of a drive, our repair team conducts a four-step check:

    1. Visual Overview
    2. Static Test
    3. Checks Under Power
    4. Alarm Codes Verification

This overview is Precision Zone's basic troubleshooting process. Once our repair team starts on the job, we use specialized and customized testing fixtures, Huntron trackers, signal generators, oscilloscopes, milli and megaohm meters, as well as any other necessary tools we have available to assure quality repair work. Most importantly, every repair is fully tested in our custom-built simulators under load with a motor to replicate real-life working environment.

Precision Zone goes as far as using heating chambers and overnight dynamic testing, when applicable, to guarantee performance of the repaired product when it arrives back with the customer.

Repair Process for Mitsubishi MR-S2 AC Servo Drives

Visual Overview

When conducting a visual check, the technician inspects the drive for any mechanical damage to the drive itself and any printed circuit boards (PCB). The technician then proceeds to verify connections are tight and correct inside the drive and there are no loose screws, wires or debris. Additionally, the unit is checked for any burn marks on the components, PCBs or chassis. During the visual inspection, excessive dirt on cooling components is noted as well as the functionality of the heat sink.

Basic Static Check

Input Module Testing

The input modules on these units can be tested by use of a digital multimeter with diode checking capabilities. Upon removing the cover, all of these terminals can be located along the terminal strip found within the unit. The 'P' and 'N' terminals are the positive and negative sides of the bus respectively.

Output Module Testing

Using the same type of test as above, the output modules can be checked as well. Our technicians are also equipped with huntron devices further verify their integrity. The 'P' and 'N' terminals are the positive and negative sides of the bus respectively.

Positive Lead Negative Lead Reading
(L/M) U 'P' Terminal 0.34V - 0.38V
(L/M) V 'P' Terminal 0.34V - 0.38V
(L/M) W 'P' Terminal 0.34V - 0.38V
'N' Terminal (L/M) U 0.34V - 0.38V
'N' Terminal (L/M) V 0.34V - 0.38V
'N' Terminal (L/M) W 0.34V - 0.38V

Common Alarms for the Mitsubishi MR-S2 Servo Drive Units

Alarm Code Description Quick Checks
10 Under Voltage
  • Verify incoming 3 phase power to the drive
  • Ensure all phases are present, balanced, and within the correct range
31 Overspeed
  • Check motor code to make sure the proper motor code/speed is selected
  • Reduce rapid traverse rate
  • Increase acceleration/deceleration time constant
  • Check cabling, especially between drive and encoder
  • Check position detector/encoder unit
32 Overcurrent
  • Check wiring
  • Meg out the motor cable and motor for issues with insulation resistance
  • Check for motor grounding or shortcuts on the drive outputs
  • if alarm happens at poer up, try to disconnect U, V, W cables (with power off) and power up. If alarm remains, check out put transistors
37 Parameter Error
  • Check control for specific parameter that is being indicated
  • Verify all jumper and switch settings
  • Make sure any option boards are properly seated and making good connection
  • Check wiring and connections
50 Overload 1
  • Ensure that the motor has not overheated
  • Check wiring
  • Meg our the motor cable and motor for issues with insulation resistance
  • Check for motor grounding or short circuits on the drive's outputs
  • If alarm happens at power up, try to disconnect U, V, and W cables (withpower off) and power up. If alarm remains, check output transistors

This list of checks for certain alarms is primarily a good starting point and if any further troubleshooting or technical support is needed feel free to contact us via phone or email to get in touch with our experienced tech support team.

Precision Zone offers free technical support on any component that you may be having issues with. We understand that when your machine goes down, your business stops. That is why our number one goal is to provide you with the best service possible so that you can get back up and running immediately. FFor any further product information or troubleshooting assistance is needed, please contact us via phone at 800-551-4420 or email us.

Precision Zone Repair Benefits for Mitsubishi MR-S2 Servo Drive Units

  • Free quotes and evaluations by our expert technicians include:
  • 12-Month Warranty on Our Parts and Labor
  • Decades of Industry Experience
  • Exchange Options
  • Rush Service Options

Contact Us To Start Your Repair Today!


Recently Repaired Products

Mitsubishi MR-S2-80A-E31 image MR-S2-80A-E31 is an
Drives-AC Servo manufactured by Mitsubishi
Discovered issues: Bad Capacitor(s), Bad Circuit Board Component(s), Excessive Dirt/Debris
Drive Type: MR-S AC Servo Drive
Axis Specification: 2 Axis
Output Capacity: 1kW/1kW
Option card: RF-312 for closed loop

Mitsubishi MR-S2-80B-E01 image MR-S2-80B-E01 is an
Drives-AC Servo manufactured by Mitsubishi
Discovered issues: Bad Capacitor(s), Bad Gate Section/Board, Leaky Capacitors (Open, Corroded Traces)
Drive Type: MR-S AC Servo Drive
Axis Specification: 2 Axis
Output Capacity: 1kW/500W
Option card: no card

Mitsubishi MR-S2-100B-Z33 image MR-S2-100B-Z33 is an
Drives-AC Servo manufactured by Mitsubishi
Discovered issues: Bad Capacitor(s), Bad Gate Section/Board
Drive Type: MR-S AC Servo Drive
Axis Specification: 2 Axis
Output Capacity: 2kW/1kW
Option card: RF-332 for absolute value detection

Mitsubishi MR-S2-100B-E01 image MR-S2-100B-E01 is an
Drives-AC Servo manufactured by Mitsubishi
Discovered issues: Bad Circuit Board Component(s)
Drive Type: MR-S AC Servo Drive
Axis Specification: 2 Axis
Output Capacity: 2kW/1kW
Option card: no card

Mitsubishi MR-S2-100A-E01 image MR-S2-100A-E01 is an
Drives-AC Servo manufactured by Mitsubishi
Discovered issues: Bad Magnetic Contactor, Relay, Bad Power Section/Board, Excessive Dirt/Debris, Leaky Capacitors (Open, Corroded Traces)
Drive Type: MR-S AC Servo Drive
Axis Specification: 2 Axis
Output Capacity: 2kW/2kW
Option card: no card

Mitsubishi MR-S2-40A-E01 image MR-S2-40A-E01 is an
Drives-AC Servo manufactured by Mitsubishi
Discovered issues: Bad Circuit Board Component(s), Bad Power Section/Board, Excessive Dirt/Debris, Leaky Capacitors (Open, Corroded Traces)
Drive Type: MR-S AC Servo Drive
Axis Specification: 2 Axis
Output Capacity: 500W/500W
Option card: no card

Mitsubishi MR-S2-40A-Z33 image MR-S2-40A-Z33 is an
Drives-AC Servo manufactured by Mitsubishi
Discovered issues: Bad Circuit Board Component(s)
Drive Type: MR-S AC Servo Drive
Axis Specification: 2 Axis
Output Capacity: 500W/500W
Option card: RF-332 for absolute value detection

Mitsubishi MR-S2-80A-Z33 image MR-S2-80A-Z33 is an
Drives-AC Servo manufactured by Mitsubishi
Discovered issues: Bad Capacitor(s), Bad Circuit Board Component(s), Bad Cooling Fans, Leaky Capacitors (Open, Corroded Traces), No Display
Drive Type: MR-S AC Servo Drive
Axis Specification: 2 Axis
Output Capacity: 1kW/1kW
Option card: RF-332 for absolute value detection