Set up of stepper motion control system

[y3k]

Hi,

Currently I am using the NI controller card 7734 and the UMI 7764 connected to my 3rd party driver and a EAD stepper motor with an encoder attached to it( The encoder has 5 ports- B,5v,A,I,G).

I connected the wiring connections according to the forums online. The STEP and DIR ports from the UMI 7764 are connected to my 3rd party driver.

The encoder A, B and Index are connected to the UMI as well.

The +5 and GRD ports from the encoder are connected to the UMI as well.

I have a 5V supply to the UMI.

My encoder has 200 CPR thus I input 800 CPR in MAX. When I started the MAX program the 1-D interaction is running well. However there is no rotation of my stepper motor. What went wrong or did I miss out any connections?

Regards

Alvin

[Brian_Beal]

I suspect that it has to do with the connections to your drive.  Please let us know what drive you are using.

[y3k]

Hi

I am currently using the Dragon Driver model 29A55. There are 10 screw terminal block namely

1) Step out

2) Step in

3) +5V

4) Half/Full step

5) CW/CCW

6) Enable

7) GND

😎 Fast

9) Slow

10) GND

On the right hand side there is a six screw terminal block namely

1&6)  Power supply

2&3)  A

4&5)  B

Please advice on the connections. Thank you

Alvin

[Buechsenschuetz]

Besides the "usual" signals like STEP, CW/CCW and ENABLE, your motor driver seems to have some specific signal connections and/or configuration terminals. Usually it is the best to refer to the manual/instructions of the manufacturer of the motor driver, they usually give hints how to use all those terminals and how to connect the driver to a controller board.

[Buechsenschuetz]

< Step out> probably a signal providing one pulse per full step < Step in> connect this to the STEP terminal of UMI < +5V> connect this to the +5V terminal of UMI (check power consumption!!) < Half/Full step> this terminal probably controls whether the motor moves one full step or a half step for each step pulse < CW/CCW> connect this to the DIR terminal of UMI connect this to the EN terminal of UMI (check voltage level, if no information leave this terminal open for a test) connect this to GND of UMI < Fast> ?? < Slow ?? <10) GND

1&6)  Power supply> connect this to a power supply with suitable voltage and current rating, usually motor drivers run on 24VDC, current rating is also determined by the motor connected

2&3)  A> connect this to the phase A wires of the motor, there should also be a +/- designator

4&5)  B> connect his to the phase B wires of the motor direction of turning is not only determined by CW/CCW setting but also by proper wiring of the phase wires Since there is no information about voltage level of the ENABLE pin, and what to do to with the FAST and SLOW terminal, this setup is NOT complete and maybe it will not run this way.

[y3k]

Hi

I found the manuel for the drive online and I have attached it. The connection from the motor to the driver and the encoder to the driver has been established. However I am not sure about the connections between the UMI 7764 and the driver. For the driver I have connected (1)<step out> and (2)<step in> together and (9)<slow> and (10)<GND> together.

Can you advise on the connections? Many thanks

Alvin  

[Buechsenschuetz]

As far as I can see, the STEP_OUT is an output of an internal step pulse generator. If you are using an external step pulse into STEP_IN, you don't have to connect STEP_OUT. Also, the FAST and SLOW inputs seem to select the pulse rate range for the internal oscillator only, it seems as if their connection is not relevant when using external pulse source. You mentioned that you connected the encoder to the driver unit, I cannot see any terminals for an encoder. Usually, if you are using a NI motion controller, the encoder is connected to the motion controller board (via the UMI box if necessary). Don't forget to set the motor current properly. Check the rating of the motor you are using. Effective current also depends on the wiring of the coils. As a starting point, I would recommend setting the driver current to one half ( 1/2 ) of the rated motor current.

[y3k]

Hi there again,

Thanks for the advice on the connections. Now that the set up is done, I need to achieve, let's say, a step output of 5rev/s for 10 secs- both clockwise and counterclockwise direction.

Can this be done with solely measurement and automation explorer alone?Or do I need Labview to program it?

Lastly, for stepper motor operating in an open loop, would any calibration be needed?

alvin

[VGA_CD-ROM]

Hi y3k,
You can use the 1-D Interactive control to do these simple moves for your axis in Measurement & Automation Explorer (MAX). This can be found in MAX under NI-Motion Devices » (Your motion card) » Interactive » 1-D Interactive

In there you can choose an axis, choose open-loop mode, and choose relative position for your operation mode so that you can move CW or CCW relative to the position you're currently in. You can then specify your velocity and a target position (in steps, which would be X steps/rev * 5 revs/min * 1/60 mins/second * 10 seconds), and press apply to begin your move. You can set the target position as negative to go in the other direction.

As for software-based calibration, if you are operating in an open-loop configuration, you will not be able to calibrate your motion controller for your motor. This requires a closed-loop system so the controller can determine where the motor is versus where it expects it to be, and adjust its output accordingly. If you meant mechanical calibration to improve the motor's response to the controller, that is something you would need to check your motor's service manual about.

For simple applications and when using well-maintained equipment, you often don't need to perform any controller calibration.


Message Edited by VGA CD-ROM on 02-20-2008 10:18 AM

[y3k]

Hi there,

I currently have a problem with my stepper motion set up. It seems like the stepper motor only stops running when I click on "kill" in MAX. When the motor is not running, it can be started by clicking "start" or "halt". Seems like only when the axis is killed, the motor will stop running. How can I configure such that the motor starts running when I click on "start" and stops when I click on "halt" in MAX?

Thank you