Got my MR-J2S40 Mitsubishi servo drives turning and a few questions..

[CncForMe]

First WOW these AC servos are amazing. The resolution, torque, and individual steps (131072) per rev is just awesome! Proud to own such great technology and I have only just jogged these things around in Mitu’s PC Config software. Anyways I could use some feedback/advice on how hard I should push the servos in terms of loading. I know you can get closer to their peak power output than steppers because of the encoder feedback/error detection but how close would you go?


Some numbers, I have 184oz/inches of continuous torque and 3000rpm nominal per servo. Building a dual drive gantry, thinking of about something between like a 6 to 9 to 1 reduction. So tell me if I have the engineering right, going rack and pinion. 184.10oz/in x 6(reduction) x 2(radius) because I have a one inch diametrical pitch pinion thus the radius is the lever arm which in my case is .5 . So almost 140 pounds of force per motor sound right???? My gantry weighs around 100 pounds, 10' x 4' table for routing and plasma. Seems more than sufficient to me, especially if you look at peak torque and rpm that is available. Peak torque is almost triple this for 10 seconds and peak rpm can hit 5000. So maybe even more reduction would be necessary to take advantage of this reserve punch.


Also does anyone know how to hook up a smooth stepper card to use Quadrature pulses? I guess you need the right breakout board or maybe it is simpler than that. Quadrature would really allow me to utilize the full resolution of the drives. Thanks to all posters in advance. See my website for pics of my setup to be. Must type in your browser PhiladelphiaMachineWorks.com

[battwell]

did the config software come with the drives? ive been looking all over for it!

[CncForMe]

I, ahhhh, found it on line... for free. You no how it is, I did buy four of their drives. I feel like it should be free anyways. Nice program pretty simple but everything you need is there. Much easier than using the drive buttons to config everything. The test functions are great too much to hookup everything just to turn some motors. Only thing that I think could be better is the damn interface plugs man are those hard to solder, too small. Search for the MR Config part number that's how I found it

[battwell]

i ve searched everywhere but cant find it!
any chance you have a link?
or could email me something?
tried searching mr configurator etc.

[Larken]

Building a dual drive gantry, thinking of about something between like a 6 to 9 to 1 reduction. So tell me if I have the engineering right, going rack and pinion. 184.10oz/in x 6(reduction) x 2(radius) because I have a one inch diametrical pitch pinion thus the radius is the lever arm which in my case is .5 .

Go with a pinion of at least 18-20 teeth. This will give a smoother less cogging motion.
Then your 6-9/1 reduction should be good. Same, if your using a timing belt for reduction don't go less than 18 teeth on the small gear. 5M15 belt should be good.
We use 20 pitch rack on our routers. (from Moore Gear)

Also does anyone know how to hook up a smooth stepper card to use Quadrature pulses? I guess you need the right breakout board or maybe it is simpler than that. Quadrature would really allow me to utilize the full resolution of the drives.

Why , are you wanting to run double closed loop ? I don't think mach does anything with an encoder input but display it.


Larry K

[Al_The_Man]

AFAIK the drive produces a pseudo encoder output that is programmable by parameter (27) default 4000p/rev.
The most demands on a system is during the accel/decel, and the motor to load inertia ratio is the critical number (must be under 10:1) and increases as acceleration increases, try one of the sizing programs, if you search here for Kollmorgen you will find the download link, it is on the ElectroMate site.
Al.

[CncForMe]

I just wanted more resolution but after running the numbers i should be good with just step and direction input.


Battwel sent you an emial with the MRZJW3-SETUP151E software.

[krazatchu]

Hi...

I've just used the same drive with a HC-KFS43 Servo for an art project...
For controlling the driver, I used step and direction....

Interfacing it with 5v logic from an AVR was done with a 2n2222 and some other parts...
I can give details on the interface if you want...

I'm having some trouble tuning it, but that is a new thread...

[battwell]

cnc for me thanks for the email. works great!

any chance you came accross the software for mr-j2 series too? not j2s.

[battwell]

just in case you havnt come accross this yet. the mitsubishi drive is looking for a 24 volt step/direction input not 5v

i tried feeding it with 5 volts into the interface but it wouldnt have it.

i used a uln2803a chip fed with 24 volts accross pins 9 and 10 (pin 10 24v pin 9 common)
inputs into pins 1 to 8 give outputs on pins 18 to 11 (opposite one to one so nice and easy) works perfectly at all frequencies i tried.
using mach3 and 100 steps per mm i can get 15000 mm per minute which is as fast as my commercial cnc. (ive set up electronic gearing in the drive)


with the 2803a chip you need no other circuitry, pull up resistors etc its all in there!
having 8 inputs and outputs one chip is good for 4 axis.
hope this helps anyone else.

[krazatchu]

Hey...

I used the open collector input...
With a 2n2222 and a 1k resistor....
It's working allright...

Michael

[macona]

The Mitsubishi drives work just fine off of 5v logic input. Heres the thing. There is an error in the manuals. Where they show wiring to a pulse control the + and - labels are backwards. I found out this the hard way...

So pins 12 and 13 are positive and 2 and 3 are negative. There is a 91 ohm resistor in series with the opto and a reverse polarity protection diode there as well.

Anyways my Hercus Computurn is running with two MR-J2 drives right now. 400w on the Z and 200w on the X. Both running on the