Need Help!- I need help with getting a Stepper driver

[purecnc]

Im trying to get an old Shopbot machine working for School.
My dad bought this machine from friend like 12 years ago and has only used it a couple times and all the computer software and stuff is outdated and a few things are missing.
its one of the first shopbot has made so they have no documentation for it.
More info, the machine is 12ft long and about 8ft wide the
it will be cutting foam blocks
and it has
2 = X-axis stepper motors
1 = Y-axis stepper motor
and
1 = Z-axis stepper motor (and an extra that im not going to use yet)
I have 2 pics of the stepper motors
the first is the X and Y axis steppers
the second is the Z axis stepper

im on a max budget of $200 max for the stepper driver cause im going to buy mach 3
will this driver work for these motors?
5 Axis Stepper Motor Driver Board Controller TB6560 +CD - eBay (item 180586505509 end time Dec-11-10 22:23:06 PST)
or can anyone else suggest a driver that will work for what i have?

Sorry if i never explained myself or what im trying to do well, i have a hard time explaining

[vger]

It looks like that driver should work for you. You would set the current at minimum (1.5 Amps) for the x and y motors, and at 2 Amps for the Z motors.

Are the drivers currently in the machine not working? If they are still operational, and the power supply for them is there, you may be able to use them. Can you post some pics of the drivers in the machine?

Steve

[purecnc]

Originally Posted by vger It looks like that driver should work for you. You would set the current at minimum (1.5 Amps) for the x and y motors, and at 2 Amps for the Z motors. Are the drivers currently in the machine not working? If they are still operational, and the power supply for them is there, you may be able to use them. Can you post some pics of the drivers in the machine? Steve

Thanks for replying Steve,

The original drivers are made by shopbot so i called them up and the guy told me that only a shopbot program can run the drivers. they are funtional but the computer isnt, it is a old win 95 computer with usb 1.0 on it and i cant get past the boot screen since i dont have a old Usb 1.0 keyboard
i do have the original powersupply and that does work though but its 24v and i dont know the voltage of the motors, any idea on how to find them with the amperage and the Ohms?

i'll get a few pics of the drive for you when i can

Edit: heres a pic of the whole board
http://www.cnczone.com/forums/attach...1&d=1269467299

Edit: are the z axis steppers 3.6v? and the X, Y axis steppers 3.3v?

[James Newton]

I strongly recommend that you google around a bit to see the problems people have with those cheap Chinese drivers before you spend your money.

[vger]

James is right about some people having problems with those boards. Check out this thread...
http://www.cnczone.com/forums/genera...r_updated.html

The picture you have of the whole board is way too small to see much but it appears there are 4 individual drivers.

As to the stepper voltage... The current rating is what you will be setting the driver up for. The voltage rating on a stepper is the continious DC voltage that it would operate at for full current. Chopper drivers run with a much higher voltage than the continious DC voltage rating.

I find it difficult to believe that the drivers will work "ONLY" with a shopbot program. Is there a grand total of 9 or 10 wires connecting to each driver (including the motor leads) ?

Steve

[purecnc]

Ok, i looked into those and found a bunch of problems. thanks guys for letting me know

I uploaded some more pictures of the drive, sorry for that other 1 for being so small.

Each driver has 6 wires (well 12 but 2 of them are connected) and it connects to some type of break out board for a serial port

Heres another pic but it wouldn't upload
http://img535.imageshack.us/img535/8...1071434441.jpg

Any suggestions for a driver that can do at least 4 axis and is under $200?

Is the Hobby Cnc Pro driver any good?

[vger]

Ok, I think I get the idea now... Couple of more questions....

On each driver is a module that is attached to the common aluminum heat sink. Can you read the number on one of those modules?

It looks like there are 6 motor lead connections, is that correct?

The chips on the smaller board are a microcontroller, memory, and periphrial interface. It appears as if the drivers are simple unipolar drivers that require 4 inputs. Each input probably corresponds to an individual coil in the stepper motor. Knowing the number on the driver module will tell me for sure.

It might be possible to use those drivers as they are with the software set up to ouput motor phase signals on 4 outputs, rather than step and direction on 2. I know TurboCNC allows you to do that, but I don't think Mach3 or EMC2 have that capability. You would need 2 printer ports to use all 4 motors in that manner but it would probably work.

Steve

[purecnc]

Originally Posted by vger Ok, I think I get the idea now... Couple of more questions.... On each driver is a module that is attached to the common aluminum heat sink. Can you read the number on one of those modules? It looks like there are 6 motor lead connections, is that correct? The chips on the smaller board are a microcontroller, memory, and periphrial interface. It appears as if the drivers are simple unipolar drivers that require 4 inputs. Each input probably corresponds to an individual coil in the stepper motor. Knowing the number on the driver module will tell me for sure. It might be possible to use those drivers as they are with the software set up to ouput motor phase signals on 4 outputs, rather than step and direction on 2. I know TurboCNC allows you to do that, but I don't think Mach3 or EMC2 have that capability. You would need 2 printer ports to use all 4 motors in that manner but it would probably work. Steve

The driver chips are
"SLA7026M" then it has 4 little numbers under that "9508"

yes the steppers are 6 wire unipolar

for the software i know about the turbo cnc phase drive but i dont have 2 printer ports on my computer. i onyl have 1. and i wouldnt know the phase to use
xooooo
oxoooo
ect.

thanks

[vger]

The SLA7026's are 3 amp unipolar drivers. Here is the datasheet on them...
http://www.futurebots.com/7024.pdf
(that covers the 7024, 26, and 29) so they would require phase drive. If you look at the 4th page there it shows the truth tables for stepping in either full or half step.

The 9508 on the cihps is a date code... manufactured in the 8th week of 1995.

You could add a second parallel port to the computer (unless it's a notebook) to handle the other 2 drivers. I think that would be your cheapest option for getting it to run. Of course you would have to use TurboCNC, but it's not too bad (I've been using it for a couple of years).

It would be possible to build a small translator to accept step and driection signals and output the phase signals. It would require 5 chips total, 4 7494 shift registers to produce the phases and a 7404 inverter to handle the direction control.

Steve

[James Newton]

The SLAm driver uses that same class of chip and 4 will cost you $139.80
SLAm1: SLA 7062M Stepper Motor Controller.

A complete kit with break out board, PC parallel port and driver cables, +5 regulator for logic power and 4 drivers would cost $164.70
http://www.ecomorder.com/techref/eco...6&q=1&416056=4

[purecnc]

Originally Posted by vger The SLA7026's are 3 amp unipolar drivers. Here is the datasheet on them... http://www.futurebots.com/7024.pdf (that covers the 7024, 26, and 29) so they would require phase drive. If you look at the 4th page there it shows the truth tables for stepping in either full or half step. The 9508 on the cihps is a date code... manufactured in the 8th week of 1995. You could add a second parallel port to the computer (unless it's a notebook) to handle the other 2 drivers. I think that would be your cheapest option for getting it to run. Of course you would have to use TurboCNC, but it's not too bad (I've been using it for a couple of years). It would be possible to build a small translator to accept step and driection signals and output the phase signals. It would require 5 chips total, 4 7494 shift registers to produce the phases and a 7404 inverter to handle the direction control. Steve

Thanks Steve , i'll talk to my dad about it today.
would the small translator be hard to build/buy and do they work good?

James i'll look into the driver to thanks for posting it

[James Newton]

If you just want to translate the standard step and direction singles into a full step wave form, you can do that with two commonly available logic chips:
03.26.98 Design Ideas logic the circuit is part way down the PDF linked to from this article.

A more indepth but somehow less understandable (to me) version of the same thing is at:
Jones on Stepping Motor Midlevel Control

But honestly, that provides only full step control, and unless you have already made a PCB and have the materials handy, it's probably best to purchase a replacement stepper controller which supports more advanced modes.