Saturday,19-November-2022

Mitsubishi M700 and Servo Mitsubishi MDS-D alarm fix

EN

That is topic dedicated to alarms and trouble codes in Mitsubishi M700 control , caused by defective servo module MDS-D and low backup memory battery.

Most of that MDS-D servo units have own backup battery to keep some settings “alive”. But in my case there was common block as that one:

servo_4.jpg

Getting old and bad, the battery cause constant lose of absolute axis points. So, how that can be that issue fixed ans so on please read below :)

First here is the list of the error codes:

Z70 Abs posn error

S52 Battery voltage drop

Z73 Battery for abs data fault

and so on..

servo_1.jpg

servo_2.jpg

All axis modules in my case was connected to common battery pack:

servo_3.jpg

By the cables, I found the block at the right end of the cabinet. And it look like that:

servo_4.jpg

Then, battery been replaced:

servo_5.jpg

That remove the S52 and Z73 alarms, but still left the Z70 ones. With that matter , we will deal just in a minute.

Most important was to get rid of the servo issues. And that is because it just simply will not start:

servo_7.jpg

As it seems, that is quite common thing among the old MDS-D modules and is caused by small 33uF capacitor.

Now, need to be taken the whole servo unit out:

servo_8.jpg

open it…

servo_9.jpg

servo_10.jpg

and here is the “bad boy”:

servo_11_1.jpg

sometimes also the IC can be problem:

servo_11_2.jpg

So here is the replacement: 33uF @ 50V

servo_12.jpg

Here is the place to mention that is multilayer PCB and you need to remove it absolute carefully!!!

Once job done, you`ll see hopefully something like that:

servo_13.jpg

And I was left finally with that ones:

servo_14.jpg

For them to be solved, you need to get full access to the parameters, so on the password request write : MPARA

When there, go to ABS-set

servo_15_1.jpg

set the marked position to 1 and you`ll get the “state” condition ready. Please remember, that you need to do that for any axis what relay to battery backup!

Then, after restart of the NC-Control, you`ll get hopefully to that point:

servo_16.jpg

Hope that small write up was in any use to you!