Difference between revisions of "Using SinCos encoder"
From Granite Devices Knowledge Wiki
| [checked revision] | [checked revision] |
(Created page with "To use SinCos encoder sit analog sine and cosine voltage outputs, select the SinCos encoder from Granity's feedback device list FBD. The interpolation factor determines ho...") |
|||
| Line 12: | Line 12: | ||
#Update feedback device resolution [[FBR]] to match the new setting (see details in above) | #Update feedback device resolution [[FBR]] to match the new setting (see details in above) | ||
#Check and update velocity/acceleration limits if needed | #Check and update velocity/acceleration limits if needed | ||
| + | {{tip|With very high resolution feedback devices, one may run into a problem of limited value range of velocity and acceleration parameters (i.e. velocity limit is set to maximum, but higher value would be desired). <br/><br/> | ||
| + | To overcome this, reduce [[DIV]] parameter value which sets the scale of velocity/acceleration limits. I.e. if you change DIV from 100 to 10, you will get 10 times more range in velocity limit. Also change [[MUL]] accordingly if the original scaling of setpoint is desired.}} | ||
| − | [[ | + | [[Category:Setup_guides]] |
Revision as of 09:43, 9 August 2015
To use SinCos encoder sit analog sine and cosine voltage outputs, select the SinCos encoder from Granity's feedback device list FBD. The interpolation factor determines how many times the resolution is increased from the base resolution. Choices are:
- 16X = equals resolution of encoder which has 16 times higher line count than non-interpolated encoder. I.e. 1000 lines encoder would yield 1000*4*16=64000 couns/rev resolution.
- 64X = equals resolution of encoder which has 64 times higher line count than non-interpolated encoder. I.e. 1000 lines encoder would yield 1000*4*64=256000 couns/rev resolution.
- 256X = equals resolution of encoder which has 256 times higher line count than non-interpolated encoder. I.e. 1000 lines encoder would yield 1000*4*256=1024000 couns/rev resolution.
In addition to choosing interpolation factory, the feedback device resolution parameter FBR need to be set accordingly: multiply the base resolution with interpolation factor. I.e. with 1000 line encoder and 16X interpolation, set FBR to 16000.
 | As resolution of feedback device changes, the motor travel per one "step" also changes. This affects the velocity and acceleration speed settings. Always check and update other parameters after interpolation factor is changed. |
Setup procedure
- Choose FBD SinCos encoder with desired interpolation factor
- Update feedback device resolution FBR to match the new setting (see details in above)
- Check and update velocity/acceleration limits if needed
 | With very high resolution feedback devices, one may run into a problem of limited value range of velocity and acceleration parameters (i.e. velocity limit is set to maximum, but higher value would be desired). To overcome this, reduce DIV parameter value which sets the scale of velocity/acceleration limits. I.e. if you change DIV from 100 to 10, you will get 10 times more range in velocity limit. Also change MUL accordingly if the original scaling of setpoint is desired. |
