DMM DYN4 Spindle Set-up - receiving 1V at power up - voltage drift (solved)

[cnckeith]

and watch martys video on it..

viewtopic.php?f=61&t=2446

[Nick4Maker]

Thanks again Keith, I have a direction to chase down.

[Nick4Maker]

Keith,

I verified M5 is configured in the Wizard. So I'm stuck for next steps.
Please note, the spindle moves even when Acorn Program is not started, simply panel being on.
Also, I took the Output 5 out, just to see what hapens and the spindle still turns.

I'm thinking about your contactor workaround, from M5 to power up & down the drive.
Going on the same idea, could I put the 0-10V in a relay, that would be controlled by the M5 signal? I simply do not know if this is a dumb idea, however my thinking this method would be less harsh on the system to remove 0-10V signal vs. powering the drive on & off every time the motor stops.

Really appreciate your help, I'm swimming in uncharted waters.

Thanks,

Nick

[mick41zxr]

Nick can you post a screen shot of your outputs from the wizard. As Kieth has stated you need to be able to enable the drive separately from the Analogue circuit. I use a different servo a spindle & use an separate output for spindle fwd & rev as you would with a VFD.
Looking at DMM Manual it only had input for analogue circuit when in speed mode.
In your case I would use a pair of relays that would close the analogue circuit with a M3 command & invert it the analogue signal with M4.
With M5 command or start up, both Analogue +ve & -ve would be switched to Common. Not ideal but this should prevent drift when system idle.
Something like sketch below.
Also check the tech bulletins for the diode to install across the analogue outputs.
Regards,
Michael

[Chaz]

For what its worth, my setup also spins the spindle slightly (normal VFD on induction motor) IF (and its IF) the start signal is bypassed and forced on. Before I fully wired my relays and during testing, I'd see this.

[Nick4Maker]

Thanks for the awesome feedback and definitely a good path to chase.
It won't be till the weekend to dig into it. I will report back results.

[martyscncgarage]

Analog signal on Acorn is never at perfect ZERO. Nor should you rely on that.
You need to be able to inhibit the drive, in this case you would apply an inhibit signal to the drive and it should set it free and ignore commands until the inhibit is removed. You could use SpindleBrakeRelease I would think, that would drive a relay that controls the inhibit on the DYN4 drive.

I really don't know the infatuation with trying to use a servo motor as a spindle drive other than the fact that the encoder is built onto the motor. You have to still run the servo to the spindle at 1:1. If you are trying to drive the DYN4 at 120V, then your servo RPM will be limited. If you drive it at 240VAC, then you'll have more usable RPM.

There is also a CRAZE to try and use the same servo as a "C" axis, that is, its a spindle motor and then when commanded, its a positional motor.
That's all well and good but it takes special firmware on DMM's part to do that and maybe even some special PLC work on the Centroid side.

You still need to lock the spindle or be cognizant of the cutting forces imposed on the spindle, in which one is asking the servo to try and hold position with no other help like a physical brake on the spindle. If not, when you push the drive to much, it will fault and free wheel, which, might be catastrophic....


Marty

[Nick4Maker]

Marty,
As far as I know, the only inhibitor to the DMM set-up is the dead-zone, which is lower than the voltage drift. I need to reach out back to DMM and ask why is the motor rotating if the input signal M5 is not sending. How is the M5 signal utilized.

Thanks, Nick

[martyscncgarage]

Marty,
As far as I know, the only inhibitor to the DMM set-up is the dead-zone, which is lower than the voltage drift. I need to reach out back to DMM and ask why is the motor rotating if the input signal M5 is not sending. How is the M5 signal utilized.

Thanks, Nick

You have M3 SPINFWD (OUTPUT)
M4 SPINREV (OUTPUT)
M5 cancels both of them it has NO OUTPUT
SPINDLEBRAKE (OUTPUT) Active when an M3 or M4 is called, cancelled when an M5 is called.
The DYN4 drive most certainly has an ENABLE input signal. I would try and use SPINDLE BRAKE to activate/deactivate it.

[Nick4Maker]

Marty,

The drawing that I followed does not include wiring diagram for M3 & M4, where the pin out would be identified. I believe the file was call DMMAcornSpindle_R2.pdf. If anyone has a newer diagram that utilizes M3 & M4, I love to look it over.

I just word back from DMM support, they will try to recreated the issue.

Thanks, Nick