[Emc-users] Running Mitsubishi Meldas DC servo motors with LinuxCNC

[Leonardo Marsaglia]

Hello to all!

A few months ago our Mazak spindle died and we replaced it with a new one
of the brand Yaskawa. The lathe is behaving well but it's a good idea to
replace the control with a LCNC machine following a planned schedule just
to avoid the emergency of replacing it in case of a sudden failure on the
Mazak original cpu.

I've seen that there's a link on the wiki with a VMC Mazak retrofitted to
LinuxCNC. (http://webpages.charter.net/bengvall/emc/emcconversion.html).

From what I can read on that link and what I found about the DC servos on

our Mazak, both work the same way comparing the phase to eliminate the
following error. I've got some info on the manuals that came with my lathe
that says the following:

X Axis Servo Motor Z Axis Servo Motor
HD81-125 HD101-12
0.8 Kw - 1.5 Kva 1.1 Kw - 2.2 Kva

Here are two links to pictures of the drivers to see if there's a
possibility to use them with LinuxCNC or if it's better to replace the
drivers for simpler ones.

Loading Image...

Loading Image...

What I find a little strange is the power of the motors, I thought that for
the size of this lathe 0.8 and 1.1 kw it's not that much, but may be that's
because I'm not used to work with servos, I only worked with steppers so
far. Although the ballscrews on both axis are really easy to move by hand
so this might be the right specs for the motors.

Sorry for the long description but my question is: Is it possible to use
these drivers? or is it going to be a lot of trouble to get them to work
with LinuxCNC??

Thanks as always for your help!

[Leonardo Marsaglia]

It seems that something went wrong with the last part of the message and
it's hidden.

It was:

Sorry for the long description but my question is: Is it possible to use
these drivers? or is it going to be a lot of trouble to get them to work
with LinuxCNC??

Thanks as always for your help!

Post by Leonardo Marsaglia
Hello to all!
A few months ago our Mazak spindle died and we replaced it with a new one
of the brand Yaskawa. The lathe is behaving well but it's a good idea to
replace the control with a LCNC machine following a planned schedule just
to avoid the emergency of replacing it in case of a sudden failure on the
Mazak original cpu.
I've seen that there's a link on the wiki with a VMC Mazak retrofitted to
LinuxCNC. (http://webpages.charter.net/bengvall/emc/emcconversion.html).
From what I can read on that link and what I found about the DC servos on
our Mazak, both work the same way comparing the phase to eliminate the
following error. I've got some info on the manuals that came with my lathe
X Axis Servo Motor Z Axis Servo Motor
HD81-125 HD101-12
0.8 Kw - 1.5 Kva 1.1 Kw - 2.2 Kva
Here are two links to pictures of the drivers to see if there's a
possibility to use them with LinuxCNC or if it's better to replace the
drivers for simpler ones.
http://imageshack.com/a/img537/5573/lgfKjB.jpg
http://imageshack.com/a/img743/4134/rk1IuG.jpg
What I find a little strange is the power of the motors, I thought that
for the size of this lathe 0.8 and 1.1 kw it's not that much, but may be
that's because I'm not used to work with servos, I only worked with
steppers so far. Although the ballscrews on both axis are really easy to
move by hand so this might be the right specs for the motors.
Sorry for the long description but my question is: Is it possible to use
these drivers? or is it going to be a lot of trouble to get them to work
with LinuxCNC??
Thanks as always for your help!
--
*Leonardo Marsaglia*.

[andy pugh]

On 19 November 2014 01:05, Leonardo Marsaglia

Post by Leonardo Marsaglia
http://imageshack.com/a/img537/5573/lgfKjB.jpg

Google images suggests it is a Mazatrol TRA31
http://www.dubuque-forsale.com/OLD-ADS-FROM-PREVIOUS-YEARS/2007/June/Mitsubishi-meldas-mazatrol-tra-31A-31-servo-drive-TRA31.php

There is a manual of sorts here:
http://www.meau.com/functions/dms/getfile.asp?ID=010000000000000001000000465000000
but I am not sure that it answers the important questions.

[Jeff Epler]

this thread has a reverse-engineered pinout for "ZP1".
http://www.cnczone.com/forums/mazak-mitsubishi-mazatrol/77549-mitsubishi-tra41-servo-drives-interface-help-please-2.html

as you might have expected, it looks like the amp is analog velocity
input.
Loading Image...

Andy's PDF shows resolver feedback.

Both Mesa and Pico have solutions for analog servo amp + resolver
feedback that work nicely with LinuxCNC.

Jeff

[Leonardo Marsaglia]

Post by Jeff Epler
this thread has a reverse-engineered pinout for "ZP1".
http://www.cnczone.com/forums/mazak-mitsubishi-mazatrol/77549-mitsubishi-tra41-servo-drives-interface-help-please-2.html
as you might have expected, it looks like the amp is analog velocity
input.
http://innovative-rc.com/tra41.jpg
Andy's PDF shows resolver feedback.
Both Mesa and Pico have solutions for analog servo amp + resolver
feedback that work nicely with LinuxCNC.

That forum discussion pretty much solves all my doubts. It seems the driver
uses tacho generation to close the speed loop within itself, and the only
signals I need to replace are the analog voltage for the velocity command
and some of the ready and fault signals to make it work. Also the pin
information is a great help to start testing.

I'm not sure about one thing in the pictures of my drivers and it's the
fact that there's a connection between the two of them, I'm going to see if
I can find out something on my PDFs but I'm not sure about what that might
be for.

I'm planning on use the resolvers as you suggested since they work really
great and also everything is already mounted so practically I don't have to
touch anything of the mechanical units.

I hope I can do some testing soon because replacing the original control
will give me a lot of new functionalities.

Thanks Jeff for info!

[Kirk Wallace]

Post by Jeff Epler
this thread has a reverse-engineered pinout for "ZP1".
http://www.cnczone.com/forums/mazak-mitsubishi-mazatrol/77549-mitsubishi-tra41-servo-drives-interface-help-please-2.html
as you might have expected, it looks like the amp is analog velocity
input.
http://innovative-rc.com/tra41.jpg
Andy's PDF shows resolver feedback.
Both Mesa and Pico have solutions for analog servo amp + resolver
feedback that work nicely with LinuxCNC.
Jeff

Not that it means anything, but I got the same impression. It looks like
a brushed DC motor with tachometer and resolver. The bit I haven't
worked out is where the velocity input connection is. See attached.

[Leonardo Marsaglia]

Not that it means anything, but I got the same impression. It looks like a
brushed DC motor with tachometer and resolver. The bit I haven't worked out
is where the velocity input connection is. See attached.

Yes indeed kirk. They are Mitsubishi DC servos, and the drivers look like
they are Meldas, although they have the Mitsubishi logo.

They have the tachometer on the motors, and resolver directly coupled on
the screws.

[Leonardo Marsaglia]

Post by andy pugh
http://www.meau.com/functions/dms/getfile.asp?ID=010000000000000001000000465000000
but I am not sure that it answers the important questions.

Thanks as always Andy!. There's an interesting section there about how to
tune the parameters using the presets on the driver. I think I saw
something like that in one of the PDFs that I have, I don't know if it's
the same. I hope I don't have to touch any of that, since the mayority of
those parameters are factory set up.

[robert - Innovative-RC]

hi
looks the same servos as on the M0 which is a machine i retrofitted, its
a Mill but the same deal.... check the linuxcnc forum i put alot of info
on the drives on there when we did our retrofit with the old DC servo
drives...


if you need to know anything else let me know ill try and help the best
i can...

what is the melda control model? or more so what are the servo drive
numbers i might have a manual of sorts

rob

[Leonardo Marsaglia]

Post by robert - Innovative-RC
hi
looks the same servos as on the M0 which is a machine i retrofitted, its
a Mill but the same deal.... check the linuxcnc forum i put alot of info
on the drives on there when we did our retrofit with the old DC servo
drives...
if you need to know anything else let me know ill try and help the best
i can...
what is the melda control model? or more so what are the servo drive
numbers i might have a manual of sorts
rob

Hello Rob and thanks for your interest in helping me!

I was trying to find your posts on the forum but there are so many that I
can't. Can you point me to the post if you remember the name of it? or may
be your user name on the forum?.

The control of the machine is a Mazatrol T1. The servo motors are
Mitsubishi, and the drives are Meldas. The servo drives model numbers are
TRA-31A and TRA-41A.

The main concern for me is how to set up the connection to run the drives
with LinuxCNC. From what I could read, it seems that if I let everything as
it is, and run the drives with the ready signals and the analog voltage for
the velocity they should turn. The tachos will be telling to the drives the
actual speed and I would only have to close the loop on LinuxCNC using the
resolvers. I guess it's not more difficult than that. But I would love to
hear suggestions!

[robert - Innovative-RC]

HI there

going from memory here but you need two volages to the drvie so need a
power supply thats all, as control does that right now from its power supply

then feed the tachos back into the drive, on the M0 they went into the
control card, then back out that was all, so was a case of moving the wires.

then anlogo in yes +10 to -10v
here is forum link
http://www.linuxcnc.org/linuxcnc/index.php/russian/forum/30-cnc-machines/559-emc-gets-fitted-to-a-leadwell-cnc-vmc

sorry should of said the title etc

you can always find me on IRC under the name, rob_h
31A im sure i have a manual ill look at work today migth be lucky and
have it in PDF also, some used to be on Mitsubishi website

rob

Post by Leonardo Marsaglia

Post by robert - Innovative-RC
hi
looks the same servos as on the M0 which is a machine i retrofitted, its
a Mill but the same deal.... check the linuxcnc forum i put alot of info
on the drives on there when we did our retrofit with the old DC servo
drives...
if you need to know anything else let me know ill try and help the best
i can...
what is the melda control model? or more so what are the servo drive
numbers i might have a manual of sorts
rob

Hello Rob and thanks for your interest in helping me!
I was trying to find your posts on the forum but there are so many that I
can't. Can you point me to the post if you remember the name of it? or may
be your user name on the forum?.
The control of the machine is a Mazatrol T1. The servo motors are
Mitsubishi, and the drives are Meldas. The servo drives model numbers are
TRA-31A and TRA-41A.
The main concern for me is how to set up the connection to run the drives
with LinuxCNC. From what I could read, it seems that if I let everything as
it is, and run the drives with the ready signals and the analog voltage for
the velocity they should turn. The tachos will be telling to the drives the
actual speed and I would only have to close the loop on LinuxCNC using the
resolvers. I guess it's not more difficult than that. But I would love to
hear suggestions!

[Leonardo Marsaglia]

Post by robert - Innovative-RC
HI there
going from memory here but you need two volages to the drvie so need a
power supply thats all, as control does that right now from its power supply
then feed the tachos back into the drive, on the M0 they went into the
control card, then back out that was all, so was a case of moving the wires.
then anlogo in yes +10 to -10v
here is forum link
http://www.linuxcnc.org/linuxcnc/index.php/russian/forum/30-cnc-machines/559-emc-gets-fitted-to-a-leadwell-cnc-vmc
sorry should of said the title etc
you can always find me on IRC under the name, rob_h
31A im sure i have a manual ill look at work today migth be lucky and
have it in PDF also, some used to be on Mitsubishi website
rob

Thank you Rob for the link and for your help! I'm going to check out now
the forum to know a little more about how you did it.

So the drivers work with +/- 10 volts, that's great because I couldn't find
anything about that yet, but anyway I could measure the input of the
drivers since the machine is working.

[andy pugh]

On 20 November 2014 02:16, Leonardo Marsaglia

Post by Leonardo Marsaglia
The main concern for me is how to set up the connection to run the drives
with LinuxCNC. From what I could read, it seems that if I let everything as
it is, and run the drives with the ready signals and the analog voltage for
the velocity they should turn. The tachos will be telling to the drives the
actual speed and I would only have to close the loop on LinuxCNC using the
resolvers. I guess it's not more difficult than that.

Indeed, once you find where the analogue voltage has to go and which
wire is which on the resolvers it should all be relatively simple.

With apologies to ***@pico-systems (who has a system that would work
well) I think this sounds like a perfect fit for the Mesa 5i24 and
7i49 combination. Depending on how much GPIO you need you would
probably also want one or two 7i37TA boards too. (or if you need more
GPIO than that, possibly 7i44 + N * smart-serial GPIO boards)

I don't see any mention of Resolver interfaces on the General
Mechatronics site.

[Leonardo Marsaglia]

Post by andy pugh
Indeed, once you find where the analogue voltage has to go and which
wire is which on the resolvers it should all be relatively simple.
well) I think this sounds like a perfect fit for the Mesa 5i24 and
7i49 combination. Depending on how much GPIO you need you would
probably also want one or two 7i37TA boards too. (or if you need more
GPIO than that, possibly 7i44 + N * smart-serial GPIO boards)
I don't see any mention of Resolver interfaces on the General
Mechatronics site.

It looks really less difficult than I thought now. I was afraid because in
the Mazak VMC from the wiki the author decided to replace the drives.

What I have to do know is to look for some information about the resolvers
and I think I could try it out in the near future (January most likely). My
idea is to make the first test without touching anything on the original
CNC. I think I'm going to put the PC next to the machine and move the
servos and try to tune them.

The other thing I need to control is the turret DC motor, now it's working
with hall sensors only, I guess some hal logic will work just fine.