Stepper motor drive modules - faulty?

K8200 3D Printer K8200 - Wiring and electronics
1

Hi I have just completed the electrical part of a K8200 build. Having checked all the wiring prior to connecting to the controller and installing all the software. When I use repetier to drive the stepper motors in manual mode. I find that only the X-axis motor will do anything.

Before I started to manually control the motor’s I adjusted the reference voltage as described in the instructions all to 0.425V +/-5mV using a plastic tipper trim tool.

I have read / assume that there may be a temperature related lockout on the extruder drive?

Having found that the x-axis motor & wiring seems to work. I removed the other motor connections from the controller and I tested each axis by connecting the x-axis motor to each motor port in turn. I still find that Y, Z & Extruder outputs don’t do much. The ‘step LEDs’ on the controller flash with manipulation of each axis but no motor drive.

My final test was to revert to connecting the x-axis motor to the x-axis motor output of the controller and test each of the motor drive modules in turn into the x-axis stepper module position on the control board (obviously being very careful to ensure that they are fitted in the correct orientation) I find that only two out the the four modules work??? These are supposed to be new modules and have been treated as such in accordance with usual anti-static handling procedures. Each module has probably been connected to a power supply for around 3-5 minutes.

I read that there seem to be many other users with duff stepper motor modules from the start? Is there no quality control?

Following an evening of annoyance:
1/ how do I go about getting these modules replaced?
2/ what are the typical failure modes of these modules. Is it the stepper motor driver chip itself / solder joints / components?

kind regards

Geoff
(Electronics engineer)

2

Did you try adjusting them to 0.5 or even 0.55V? This seems to be a more realistic value, to make sure they do not loose steps under any circumstances.

3

Hi,

Thank you for a prompt reply.

All four stepper driver modules were calibrated to 0.425V. With the modules that I am calling faulty there was no torque output from the motor (x-axis) that I used to test all stepper drive modules.

I understand that if the motors are on the verge of stalling, tweeking the reference voltage will have an impact on current delivered to the motor and hence an increased torque output. However two modules show no sign of life even before we start thinking about skipping steps?

regards

Geoff

4

Hi,

OK, some more time spent this evening trying the two troublesome stepper motor driver modules. I increased the reference voltage to 0.5V and connected the known to work x-axis motor. As expected nothing happens. Increasing the reference volatage to 0.55V, again nothing happens when trying to control the motors manually from Repetier.

I have now successfully tried the other two (known to work) stepper driver modules with all four motors in turn without issue.

Looks like I could do with a pair of replacement stepper motor drivers?

I would still be interested in hearing what typical failure modes of these devices are prone to?

regards

Geoff

5

Hi,

What is the procedure for obtaining a pair of replacment stepper drive modules?

Is an RMA issued?

regards

Geoff

6

Sorry for the inconvenience.
Please open a support ticket.
http://support.velleman.eu

7

Thanks,

A support ticket has now been raised