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Re: Odd things happening
Posted: Wed Jan 02, 2019 2:34 pm
by Chaz
One thing to try if not done already is a new / clean PC install. Ive had issues with weird spindle speeds previously, only way I could stop it (we never solved it) was to use a decent spec PC and not seen the problem since.
turns ratio and encoder line questions
Posted: Wed Jan 02, 2019 3:25 pm
by cnckeith
its a quadrature encoder.. multiple "line" by 4 to get the actual counts per rev. 2500 line x 4 = 10,000
Re: overall turns ratio and encoder line count questions
Posted: Wed Jan 02, 2019 3:29 pm
by TRM
I'll try that, thanks
Re: overall turns ratio and encoder line count questions
Posted: Wed Jan 02, 2019 3:45 pm
by cnckeith
what axis motors and drives are you using?
are both the axis motors belted or direct drive?
what is the pitch of the ballscrew?
post a fresh report.zip
Re: overall turns ratio and encoder line count questions
Posted: Wed Jan 02, 2019 3:58 pm
by TRM
One of the things that is happening is the analog output for the VFD is outputting .5V "1/2 a volt" when its powered up. It doesn't matter if the PC is on or not.
Re: overall turns ratio and encoder line count questions
Posted: Wed Jan 02, 2019 4:15 pm
by cnckeith
most all inverters have a threshold setting you'll need to set that parameter higher than the .5 volts for proper operation.
Re: overall turns ratio and encoder line count questions
Posted: Wed Jan 02, 2019 4:27 pm
by TRM
cnckeith wrote: ↑Wed Jan 02, 2019 3:45 pm
what axis motors and drives are you using?
are both the axis motors belted or direct drive?
what is the pitch of the ballscrew?
post a fresh report.zip
Hi Keith.
Check out the first page of this post, I posted pic's.
The motors and drives are Siemens
They are direct drive coupled to the ball screw.
Ball screw pitch is 5mm
Re: overall turns ratio and encoder line count questions
Posted: Wed Jan 02, 2019 5:15 pm
by cnckeith
yeah..saw the pics.. didn't see any info on the drive make and model.

or link to drive manual
Re: overall turns ratio and encoder line count questions
Posted: Wed Jan 02, 2019 5:18 pm
by cnckeith
thanks for the report. the report shows Z axis overall turns ratio is set to 5 should be 5.08 if screw is 5mm pitch and you are using inches.
what counts per rev settings do you the drives set for? most closed loop drives have a "gear number/ratio" or "multiplier" "dividing" parameter.. what do you have these set to? and what is the native resolution set to?
most closed loop drives have several steps per rev settings
- the steps per rev that it will expect to receive from Acorn
- the steps per rev that it will use to command one rotation of the motor (gear numebr/multiplier)
- the Encoder counts per rev (resolution of the encoder attached to the motor.
here is examples of setups of Yaskawa, Delta and Estun for reference.
http://www.centroidcnc.com/dealersuppor ... ds/306.pdf
http://www.centroidcnc.com/dealersuppor ... ds/303.pdf
http://www.centroidcnc.com/dealersuppor ... ds/297.pdf
Re: overall turns ratio and encoder line count questions
Posted: Wed Jan 02, 2019 5:25 pm
by TRM
cnckeith wrote: ↑Wed Jan 02, 2019 5:15 pm
yeah..saw the pics.. didn't see any info on the drive make and model.

or link to drive manual
https://cache.industry.siemens.com/dl/f ... _en-US.pdf