Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
Well, if you are using DYN4 servos, like most servos using absolute encoders your are already using "very short needle like pulses" in the serial encoder connections
This is why these are almost always differential.
As a concrete example, Yaskawa Sigma5 drives will accept 1 MHz step/dir or 4 M count/sec quadrature position commands.
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
I would use industrial drives and controller instead not step/dir with those high resolution encoders.
That something is rated to something does not always mean that it can be safely used in all circumstances.
For example I can stand on a needle bed, but my sole will be full of pin-pricks. :)
But we are really off topic now, because the OP requires only a bit more than 100kHz which all of those controllers can do and we talking about MHz ranges.
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
You said:
"just 400kHz"? Show me a stepper drive which can input more than that.
And tell me how safe is to put MHz signals into cables in noisy environments.
Doing that is megalomanic idiotism.
Furthermore the OP needs not much more than 100kHz frequency.
The DYN 4 uses MHz signaling in noisy environments successfully (as do many many drives)
and has a 500 KHz maximum step/dir input rate (And many servo drives take much higher)
So your original statement was basically just plain wrong...
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
I had exact problems running the Dyn4 at even 400kHz is why my original statement. Reducing the frequency to about 200kHz solved the problem.
I also had issues with several stepper drives when I have tried to run about 50kHz (some of them), above 100kHz (some others) while they were all rated to 200kHz. (Ok they were all cheap chinese drives.)
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
Quote:
Originally Posted by
OlfCNC
I had exact problems running the Dyn4 at even 400kHz is why my original statement. Reducing the frequency to about 200kHz solved the problem.
I also had issues with several stepper drives when I have tried to run about 50kHz (some of them), above 100kHz (some others) while they were all rated to 200kHz. (Ok they were all cheap chinese drives.)
Yes, many if not most Chinese step motor drives will not meet their minimum step length specs,
but I would expect the DMM servo to be better.
When you get close to the limits, accurate pulse width and spacing become more important
and this is a limitation of systems with low base clocks.
(BTW it looks like the DYN4 can run quadrature at 500 KHz = 2 M steps/sec)
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
I wanted to update this post for anyone else who may have the same issue - the Smoothstepper was installed and pulse rate set to 100kHz (max setting in Mach3). Unfortunately, the X-axis alarmed out 5 minutes into a program. It appears that the 400W DMM servos are not robust enough for the G0704. I'll be pulling them and stepping up to the 750W motors. The Smoothstepper is pretty nice with all the additional I/O it makes available, so I'll be keeping it. Thanks to Mactec54 for the good suggestions, and thanks to DMM for stellar support thus far. I'll definitely be using DMM servos on future projects.
-Mike
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
Quote:
Originally Posted by
mikegiraud
I wanted to update this post for anyone else who may have the same issue - the Smoothstepper was installed and pulse rate set to 100kHz (max setting in Mach3). Unfortunately, the X-axis alarmed out 5 minutes into a program. It appears that the 400W DMM servos are not robust enough for the G0704. I'll be pulling them and stepping up to the 750W motors. The Smoothstepper is pretty nice with all the additional I/O it makes available, so I'll be keeping it. Thanks to Mactec54 for the good suggestions, and thanks to DMM for stellar support thus far. I'll definitely be using DMM servos on future projects.
-Mike
When you use the Smooth Stepper you should have Mach3 settings Kernel speed at no more than 45Khz ( 25Khz )is the normal setting when using the Smooth Stepper, as this is not in control the Smooth Stepper is in control and the step pulse rate is coming from the Smooth Stepper so try a few more settings
In your max Frequency settings for X Y Z start at 256
In Mach3 what do you have the Motor Home / Soft limits Speed set to, lower this number
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
Ok, I'm understanding a bit better. My max frequency settings are set at the default 256. I don't have homing setup yet, so the homing speeds are all 0 at the moment.
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
Quote:
Originally Posted by
mikegiraud
Ok, I'm understanding a bit better. My max frequency settings are set at the default 256. I don't have homing setup yet, so the homing speeds are all 0 at the moment.
Ok in General Config. for Mach3 look for Lock Rapid if this is checked uncheck it and try again you may be able to lower the rapid moves with the slider on the Mach3 screen under feed rate slider for Rapid this will help to not over load the motors
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
Mactec54, thanks for the help. I've thrown in the towel. I've uninstalled the 400W servos and drives. They will ship back to DMM for exchange to 750W Nema34 motors and DYN4-H drives. I'll feedback in 2 weeks once I have the 750W motors installed. I think this is the overall best path for machine reliability. The 750W motors should allow some solid rapids on the G0704. Thanks again for the help.
Sent from my SM-G892U using Tapatalk
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
Wanted to follow up on this to close out the issue for anyone who may choose DMM 400W Nema 23 motors for a G0704 sized machine using direct drive. It turns out that the 400W Nema 23 motors from DMM and the Dyn4-L drives at 120VAC are a bit marginal for the G0704 X and Y axes. I returned them, installed the 750W Nema 34 motors with Dyn4-H drives at 240VAC and the random alarm issue hasn't appeared in a few days of machining. So in short, stay with the Nema 34 motors or use a 2:1 reduction if you must use the 400W motors.
I'll reiterate that DMM was absolutely awesome to work with. They provided support above and beyond not only with this issue, but the RMA process was fast and smooth. Also, they took the time to sketch up some wiring diagrams specifically for my BOB and held my hand through wiring up the 24VDC Z-axis brake. I'll definitely be using DMM servos on my future projects.
Thanks again to Mactech54 and those who chime in to help.
-Mike
Sent from my SM-G892U using Tapatalk
Re: DMM Servos with DYN4 Drives on G0704 Random Alarm Issue
Quote:
Originally Posted by
mikegiraud
Wanted to follow up on this to close out the issue for anyone who may choose DMM 400W Nema 23 motors for a G0704 sized machine using direct drive. It turns out that the 400W Nema 23 motors from DMM and the Dyn4-L drives at 120VAC are a bit marginal for the G0704 X and Y axes. I returned them, installed the 750W Nema 34 motors with Dyn4-H drives at 240VAC and the random alarm issue hasn't appeared in a few days of machining. So in short, stay with the Nema 34 motors or use a 2:1 reduction if you must use the 400W motors.
I'll reiterate that DMM was absolutely awesome to work with. They provided support above and beyond not only with this issue, but the RMA process was fast and smooth. Also, they took the time to sketch up some wiring diagrams specifically for my BOB and held my hand through wiring up the 24VDC Z-axis brake. I'll definitely be using DMM servos on my future projects.
Thanks again to Mactech54 and those who chime in to help.
-Mike
Sent from my SM-G892U using Tapatalk
That's good you are up and running, Dmm are great :cheers: