Rockwell Automation 20G PowerFlex 750-Series AC Drives - Manual (Page 293)

Rockwell Automation Publication 750-RM002B-EN-P - September 2013 293
Drive Features Chapter 5
Homing Activation
A homing function can be selected by either a digital input or a parameter. The
digital input is selected from any digital inputs residing on an attached I/O
module by Find Home or Return Home. To select the homing function from a
parameter set Bit 0 “Find Home” or Bit 3 “Return Home” of P731 [Homing
Control]. The homing sequence can be selected regardless of the mode selected
in P313 [Actv SpTqPs Mode]. If the drive has a feedback option module, a vector
type control must be selected in P35 [Motor Cntl Mode] parameter. If there is no
feedback option module, any type of control can be selected.
When the Find Home function is selected by either a digital input or a parameter,
either Bit 1 “Home DI” or Bit 2 “Home Maker” or both must be selected in P731
[Homing Control].
When the Return Home function is selected by either a digital input or a
parameter, a selection of Bit 1 “Home DI” or Bit 2 “Home Maker” of P731
[Homing Control] is ignored.
To activate a Homing function, a drive start command is required if the drive is
stopped. If a drive is running, the drive must be “At Zero Speed” state when the
function is selected.
Drive Stopped During Activation
If the drive is stopped, a start command to drive is required to activate a homing
sequence.
Drive Started and “At Zero Speed” During Activation
If the drive has already started and “At Zero Speed” the rising edge or toggled bit
activates and latches the homing sequence.
Drive Started and not “At Zero Speed” During Activation
If the drive has already started and not “At Zero Speed” the rising edge is ignored
and the homing sequence will not start.
Homing to Limit Switch with Feedback
Upon activation of homing the drive starts moving in Speed Control mode, and
ramp to the speed and direction set in P735 [Find Home Speed] at the rate set in
P736 [Find Home Ramp]. When the limit/proximity switch is reached the
“Homing Input” is set. The position count is latched and is considered the home
position count. The drive then ramps to zero at the rate set in P736 [Find Home
Ramp]. The drive then performs a point-to-point position move back to the
home position count in speed of 1/10 of P735 [Find Home Speed]. When the
motor is “At Position” and “At Zero Speed,” the homing sequence is complete.