Omron C200H-MC221 Operation Manual page 271

Additional Origin Search Patterns
The following error can occur if the CCW limit switch signal is too close to the origin proximity signal.
Limit switches
Origin proximity
switch
Z-phase signal
Speed
Reverse-mode Origin Searches 13
These origin searches are performed without an origin proximity switch and the initial search direction set to CW.
Limit switches
Z-phase signal
Speed
CCW
CCW
CW
Error (Origin proximity reverse error)
Appendix B
CW
251