Delta RMC101 - Manual (Page 826)

RMC100 and RMCWin User Manual
C-56
Degrees 360
Tenths of a degree 3600
Hundredths of a degree 36000
Thousandths of a rev. 1000
Ten-thousandths of a rev. 10000
For a full discussion, including examples, on scaling with stepper modules, see Stepper Scaling.
C.4.11 SSI Counts/Rev
Default: 1
Range: -32768 to 32767
This parameter is available only on SSI axes with stepper output. It is used with the Pos
Units/Rev parameter to determine the scaling between position units and SSI counts. If the SSI
feedback is not being used, enter a zero for this parameter. This will make the Actual Position
always match the Target Position, therefore eliminating the Following Error.
The sign of this parameter determines whether increasing SSI counts translates to increasing or
decreasing the current position:
Sign Increasing SSI counts means…
+ …increasing positions
- …decreasing positions
The use of this parameter is summarized by the following equation, which is applied every control
loop to convert the incoming quadrature counts to an Actual Position in user-defined position
units.
As the name implies, the recommended value to enter in this parameter is the number of SSI
counts generated in a single revolution of the motor. Therefore, for a 13-bit single-turn encoder
mounted on the same shaft as the motor, you would enter 8192 in this parameter since there are
8192 SSI counts per revolution on a 13-line single-turn encoder. However, this becomes more
complicated if the SSI feedback is on another shaft that is mechanically geared to the motor shaft
with a ratio other than 1:1. For a full discussion on scaling with stepper modules, including
examples, see Stepper Scaling.