Parker Hannifin
home | products | how to buy | support & downloads | literature | search

Click Here to go to new EM&D Knowledge Base (FAQ) site


Home to Z Channel for Rotary Applications

For a rotary application where you are homing to a Z-channel reference mark on the encoder and not using a home sensor, invert the home input level so the 6K always thinks the home sensor is active on that axis. Then when a HOM command is given, it will just rotate until the reference mark is found. It will rotate at the HOMVF velocity.

For a stepper axis:
AXSDEF0 ; Sets axis1 as a stepper
ENCCNT1 ; Enables encoder mode on axis1
LH0 ; Disables limit checking on axis1
LIMLVL001 ; Inverts home sensor to NO on axis1
HOMZ1 ; Enables Z-pulse homing on axis1
HOMVF.1 ; Sets final homing velocity to .1 rev/s
HOM1 ; Starts homing

Note that HOM1 or HOM0 makes no difference as the encoder will rotate the same direction looking for the z-reference. To reverse direction, invert CMDDIR.

Note that the TASXF bit 6 gives the encoder Z-channel state. Since the 6K decelerates from the HOMVF at the HOMA deceleration rate and the Z-channel pulse is very small, more than likely the motor will decelerate past the Z-channel and be quite repeatible. Slowing the HOMVF will tighten the repeatability.