Here at Precision Zone, one of our specialties is the repair services of Mitsubishi spindle drive units. One series that we often work on is the MDS-B-SPJ2(X) series.

The MDS-B-SPJ2(X) series spindle from Mitsubishi has a few different attributes which make unique, easy to use, and precise. Compared to the previous revision, this unit has been downsized as well as reduced in weight allowing a smaller amount of space to be used within the machine while also increasing the overall performance with high-speed DSP and IGBT units and high integration LSI. The high-speed DSP has been integrated to allow improved speed response, cutting capacity, and cutting precision while using positioning control.

This series is offered in various sizes, starting at 200W and going up to 11kW options. There are two conveniently located 7-segment displays that allow for quick troubleshooting if alarms occur and also a blue rotary dial switch next to them which is used for quick and easy drive addressing. All spindle parameters can be set from the NC side display screen allowing for easy operation and swapping of spindle drives when necessary. The main difference between the standard SPJ2 and SPJ2X is the X version is used with SJ-(V), SJ-N, SJ-P, or SJ-PF motors using C axis control functions and magnet sensor orientation.

When assessing the functionality of a drive, our repair team typically 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 MDS-A-SP & MDS-B-SP Series

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 output modules on these units can be tested by use of a digital multimeter with diode checking capabilities. Upon removing the cover, one can now access the required terminals to properly conduct this test. Our technicians are also equipped with huntron devices further verify their integrity.

Output Module Testing

Using the same type of test as above, the output modules can be checked as well.¹ Our technicians are also equipped with huntron devices further verify their integrity.

¹ Readings will vary by drive capacity, however, on each individual unit the readings should be within 10% of one another.

MDS-B-SPJ2(X) Common Alarms

List of Alarms

For a full list of Mitsubishi spindle drive alarm troubleshooting, see manual below:

The list of alarms within the manual is a good starting point for troubleshooting Mitsubishi MDS-A-SP and MDS-B-SP spindle drives. If any additional troubleshooting assistance is needed for the MDS-A-SP or MDS-B-SP or any other product, Precision Zone offers free technical support. Feel free to contact us via phone or email to get in touch with our experienced technical support team.

Precision Zone Repair Benefits for Mitsubishi Spindle Drives

1. FREE evaluation by expert technician includes:

• Visual Inspection

• Static Check

• Power Tests

2. FREE job estimate

3. 12 month warranty on our parts and labor