Stepper motor is stalling

[bgolash]

Hi
Yesterday I had a strange problem with my x axis that`s powered by a
1200 ozin motor. The first time I used it I had no problems then the
second time that day the x axis seemed to be stalling. I had not
changed any of the Mach3 settings and I manually turned the ballscrew
to see if the axis was binding... no problems with binding were
detected. Today I started up the machine and had the same problem but
I lowered the acceleration and velocity and now it works. But sometimes
the motor still stalls.Does anyone have a idea as to what caused this
sporadic problem.

Regards Barry

[Jason Marsha]

If you relocated any of your motor, or spindle wires it could be causing a problem with with induced signals, tripping your limit switches, if you have any.


Jason

[JonLed]

Have you tried swapping your X and Y drives to see if the problem follows the drive or stays with the motor? It could be somethink like a bridge rectifier only delivering half the power. This would only be valid if each drive is fed AC instead of DC. This is only a guess as you didn't give a lot of details

Jon

[bgolash]

Hi

I didn`t have much to mention to clarify the problem with the stepper because this machine has been up and running for 6 months. I have not made any changes to any electronic components or the software ...Mach3. Up until now I didn`t have any problems with any one of the three motors. I had thought about swapping the X and Y drives to help eliminate some of the troubleshooting variables. That will be my next move.

Regards Barry

[bgolash]

Hi
I thought I had this problem solved by switching the x axis
driver for a spare Gecko I had. The machine worked for two
weeks now I have the stalling problem again. I had this machine
working fine for months. I can`t seem to get a handle on the
problem. I`d appreciate some troubleshooting tips.

Regards Barry

[ger21]

Did you call Gecko? Sounds like the drive was bad? Possibly overheating due to hot weather?

[xyz100]

Mi impression is that Gecko drives require external current sensor resistor. I wonder if it goes open under heat. Since you replaced the driver with new one the resistor got relocated too. Quite often mechanical stress can make the resistor problem dissapear for a while. But it comes back later. Replace the resistor.

Also could you monitor the power supply current (not the voltage) and see if there is any difference between normal operation and stalling. If current goes higher when stalling it points to the motor problem. If current goes lower it points to the controller or wiring between controller and a motor.

[Mariss Freimanis]

Set the jumper for "NEMA-42" if your motor has 800 in-oz or higher holding torque.

Mariss

[danr50]

I've just touble shooted a similar problem. X axis didn't stall but moved extremely slow while measuring twice the amperage of the Y axis. Switch the cabling to eliminate the board and pointed to a bad Xaxis motor. Switched motors and it is the motor.

Question: System is using MDrive 34 (MDMF3424) steppers with IMS encoder and I have been quoted high dollars for a full replacement from the CNC manufacturer. Can I easily verify that it is the motor and can the stepper be replaced and matched to the original encoder?

[JonLed]

If you know what the phase resistance is supposed to be, you should be able to ohm it out and compare.

Jon

[danr50]

Jon,

I don't find any reference to the phase resistance and no help from th manufacture. Can I compare the reading from the good drive? Where would I measure from?

Danr

[JonLed]

How many leads does your motor have? What colors are the wires? What are the labels on the drive where they are connected?

Jon