Machsupport Forum
Mach Discussion => General Mach Discussion => Topic started by: cgabe on October 29, 2012, 08:45:10 PM
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Trying to set up, configure? Using ZETA 87-135 motors, ZETA4 Drives. These motors and drives are made for each other, I have used them on my previous DOS based system and they work fine. Now I want to go to Mach3. All 3 axis motors turn, both direction butTOOOOOOO slow.
Specs from compumotor say the 87-135 motor is 200s/rev or 12,800 microsteps/ rev. which number do I use in the Mach3 formula? Mach3 is set at 25,000 and the ZETA4 drives are set at 25,000 steps per rev. ( this is the default setting for the drives). My motors are connected directly to a 5TPI screw. I want my router to move at 40ipm. I have tried to understand the formula for tuning but I cant get the numbers to add up or to look anything like the sample screens in the manual.
screw is 5TPI, to move 40 ipm, motor should turn at 40x5=200 rev/min???? I just cant seem to get that 200 number to fit into the mach3 formula???in the motor tuning section. Sorry but I must be missing somthing. Can someone give me approx numbers to put into the motor tuning screen to get me close?
Thank you
Garth
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Hi Garth,
If your motor drive is set for 25,000 steps per revolution and your lead-screw requires 5 turns to progress 1 inch and you want to travel at 40 inches per minute then...
In Mach3 Motor Tuning 25,000 x 5 = 125,000 Steps per unit : Velocity = 40 : Acceleration 18 (or so).
Also check that you have Mach3 configured for Inches and not mm.
Tweakie.
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Your drives seem to be set to 64 micros steps, if you can set to 8 or 10 you would likely get better performance.
Anyway heres how you work out the steps per unit for Mach.
Motor steps per rev x microstepping x gearing x tpi
So in your case that would be (assuming you have no gearing between motor and screw)
200 x 64 x 5 = 64,000
At a velocity of 40IPM then the frequency needed for the kernel in Mach would be (40 x 64,000)/60) = 42,666 Hz or 42.666 KHz so you would need to set the kernel to 45KHz in Mach.
Hood
EDIT
My calscs are based on the " motor is 200s/rev or 12,800 microsteps/ rev" you quoted.
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gday, thanks for that hood , was about to post a question in regards to kernel speed settings but you have sorted. still would like to know about the relationship between velocity and acc? and step per unit and dir pulse settings? can you shed some light on these for me please?
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Thank you all I will try this tomorrow!
cgabe
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would like to know about the relationship between velocity and acc? and step per unit and dir pulse settings?
Attached should shed some light on what your asking.
RICH
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thank you very much rich, just what i needed :)
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Sorry guys I am still not getting results, missing somthing.
SUPER KITTY suggested setting of 125,000 steps per, velocity =40, acceleration = 18.
I cannot get this combination, as soon as I enter the 125,000 the velocity goes to 12 , if I enter40 it just changes when I hit return
Now HOOD said the steps per unit should be 64,000, not 125,000. I did up the Kernal to 45,000. What am I missing??
I have tried many combinations without sucess so I will give the system specs again just in case.
MOTOR is ---Compumotor ZETA 87-135 ( specs are on line at Compumotor site) it says 200steps per then in brackets sya 12,800 microsteps per rev. Which number is the real number??
DRIVER is -----Compumotor ZETA4 driver (specs are on line at compumotor site) and these two are made to work together, they spec the motor right on the side of the driver. The driver has many option via dip switches and I can set the "steps per rev" in the driver fromm 200 to 50,000. 25,000 is the default setting.
My axis screw rotates at approx 5rpm so my table is hardly moving but it moves reliably in both directions.
Is anyone else using Zeta drives?
The maddening thing is that my system runs fine, normal speeds, under my old DOS control but I am trying to upgrade to Mach 3.
I would gladly pay somone for their time if I could call somone for phone support.
Thank you!
Garth
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What are the dip switches set to at the moment?
Do you have any gearing between motor and screw?
Hood
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FIRST THANKYOU FOR YOUR INTEREST! Dips are as follows, 1on,2on,3off,4on,5off,6off,7off,8off, 9off,( this is the default setting for 25,000)10off,11off,12off second switches 1off,2off,3off,4on,5on,6on. Kernal 45,000. steps per 64000. vel 40, accel 18. The axis move at this setting but SLOOOOW. When I used the old DOS system controller I had the ZETA4 driver set at 2000 steps per rev, that was 6on,7on,8off,9off,. Motors are connected directly to the screw which is 5TPI
I am going to take a scope out and look at the pulse train, I have a C10 board on the PP output
thank you
PS BINGO -I went back to your first reply and decided to try 200stepx10 or 2000 microsteps, I also set the pulse width to 5us, and seps per 10000, velocity 190, accel 100 and things started moving!! so I am now close enough to start tuning etc. don't know why I set the velocity at 190 to get approx 20ipm motion but I am close enough to start investigating. THANK YOU
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Ok I would suggest you change it so somewhere in the region of 2,000 on the dip switches.
How things are worked out is as follows. Your drive is saying 25,000 because of the dip switch setting, that is only true if you have a 1.8 degree stepper but it seems you do, so
25,000 x TPI and Gearing so for your example assuming no gearing that will be 125,000 steps per unit in Mach. That is quite a high value and you would need the kernel in Mach set to 100KHz to get your 40IPM. You are unlikely to get 100KHz kernel reliably and really 25 to 45KHz should be the range you aim for with a stepper system.
If you alter the dip switches on the drive so that they equal 2000 (if possible) then your steps per unit would be 10,000 and the kernel required would be 25KHz ( the lowest and most stable)
At the 2000 setting of your drive and using 26KHz kernel your max potential axis speed would be 150IPM. Note however this is just a potential number and you may not be able to achieve that but I am just trying to show that having the microstepping set very high is often not a good thing.
Hood
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Ah I just noticed your PS bit in your last post, looks like you are getting close :)
Hood