Analog Out weirdness, please help <DYN4 as spindle motor>

[cnckeith]

https://centroidcncforum.com/viewtopic. ... 386#p66386

[cnckeith]

good info from both marty and gary

https://centroidcncforum.com/viewtopic. ... 559#p56559

[Measurement10]

Thanks guys, great info. Unfortunately i cant afford to swap motors at the moment. If i had to do it again id try something else for sure.

However i am glad to report everything is now working perfectly!

The signal isolator i posted works well with DYN4 and im no longer getting non-linear voltage offsets. The RPM is rock solid, very pleased. The DMM motor works well actually, reasonably quiet with lots of power, a good price too considering a 30% discount. For anyone else coming across this thread who is stuck in the same position as me, get the isolator and you'll be ok.

Big thanks to everyone who helped guide me to the solution, I hope everyone has a great weekend.

[centroid467]

Glad you are up and running! Feel free to post photos of the machine and things you make.

[SpacedmanSpiff]

Isolator took care of the encoder issue as well ?

[Measurement10]

Im not 100% on that yet, still need to install permanently, i hope it does.

[johannes]

I had issues with it faulting out after a stop command and creep after a stop command. Both were solved through plc programming changes...

I have a the same challenge, trying to use an AC Servo to drive a lathe spindle via a 1:1 timing belt. (My servo uses the AASD-50a drive).

Would love to hear any tips on how you were able to overcome the fault on stop challenge?
I'm using AcornSix, and driving it in Speed control mode and -10 - 0 - 10v analog outs.
I have set the drive to the highest deceleration amount, but it still faults whenever it tries to decelerate at the end of the program. E.g going from 500 rpm to zero.

Would appreciate any tips you might have.

[SpacedmanSpiff]

viewtopic.php?p=42002#p42002

Here is the thread on it. Cncnsw and Keith were instrumental in solving it.
The short version is the dyn4 drive is rather robust when dealing with backfeed from the motor as long as the drive is enabled. The issue is in the plc disables the drive when you tell it to stop. We had to put a delay in the plc to keep the drive enabled while the spindle decelerated down. Once the drive was disabled there was no creep in the spindle motor. All the best Sean

[johannes]

This sounds like my exact conclusion as well.

You need a much simpler PLC change to maintain the enable for a couple seconds after a spindle stop is commanded and the analog is zeroed.

Did you figure out how to change this?

[Lipton Loops]

After all best practices have been employed (twisted pair shielded wire, proper grounds, bypass caps, etc.), you might want to look into a signal isolator:

https://www.amazon.com/Isolator-Insulat ... B09TJTCDQ8

This product did not work. It requires 24V input, says on the sticker but not the listing. Hooked it up and no bueno. Also tried a second product which was a dud as well. Running out of ideas.

It is a signal isolator, so it does require independent power input to work. You supply 24VDC power along with your 0-10V signal, and you get an isolated 0-10V signal out.

If it "didn't work", at this point, after everything else you have tried, I'd suspect something seriously wrong with your drive.

Something like this I would imagine would solve that issue
https://www.amazon.ca/Isolation-Quantit ... B08SWDYBHM