YASKAWA SGDV series User Manual page 282

8 Fully-closed Loop Control
8.1.6 Precautions When Using an External Incremental Encoder by Magnescale
When Using an External Encoder with Multiple Zero Points and Passing 1st Zero Point in
Forward Direction and Returning after Power ON
When using an external encoder with multiple zero points, the same logic as that explained earlier for an
encoder with only one zero point applies to each zero point.
See
Zero point 1 detection position
Zero point 2 detection position
Phase-C pulse output
The phase-C pulse is also output when passing this point
in reverse, because the SERVOPACK has recorded
the position where the phase-C pulse was originally output
when first passing the position in the forward direction.
When Using an External Encoder with Multiple Zero Points and Passing 1st Zero Point in
Reverse Direction and Returning after Power ON
When using an external encoder with multiple zero points, the same logic as that explained earlier for an
encoder with only one zero point applies to each zero point.
See
Zero point 1 detection position
Zero point 2 detection position
Zero point 3 detection position
8-10
When Passing 1st Zero Point in Forward Direction and Returning after Power ON.
Scale count-up
direction
Power ON
Zero point 1
When Passing 1st Zero Point in Reverse Direction and Returning after Power ON.
Scale count-up
direction
Power ON
Phase-C pulse output
Zero point 1
Zero point 1 Zero point 2
Even after zero point 1 has first been passed
in the forward direction, the phase-C pulse is not
output here because zero point 2 is passed
in reverse direction.
Zero point 2 Zero point 2 Zero point 2
Phase-C pulse is not output when passing
a zero point in reverse direction.
Time
Zero point 2
Time
Zero point 3 Zero point 3