Rockwell Automation 20D PowerFlex 700S AC Drives with Phase II Control Reference Manual - Manual (Page 170)

170 Rockwell Automation Publication PFLEX-RM003E-EN-E - January 2011
Chapter 1 Detailed Drive Operation
Standalone Drive Homing
without DriveLogix Overview
Many positioning applications require the ability to find the “Home” position of
the positioning device when an absolute device is not present. The ability to use
the Homing feature without a DriveLogix processor has been added in firmware
version 3.003. The Homing feature will home to a switch or an encoder marker.
An additional digital input selection has been added to digital inputs 1 and 2 for
use by the internal homing routine for the “Home Switch”.
Digital inputs 1…6 can be programmed for “Find Home” and “Return Home” in
firmware version 4.001. The homing function supports separate acceleration and
deceleration values. The value specified in parameter 1122 [Home Speed] can be
positive or negative; when the value is negative the drive will run in the reverse
direction. The motor direction can also be controlled by setting bit 26 “Home
Dir” in parameter 740 [Position Control].
Parameter 1123 [Home Position] can now be programmed in firmware version
4.001. The actual position (displayed in parameter 763 [Position Actual]) will be
updated to the value of [Home Position] after the homing sequence has
completed.
Homing Sequence of Operation Descriptions
Note: The commanded positions are not reset to zero automatically when a
homing sequence is initiated. The user is responsible for setting the
commanded position to zero before a homing sequence is initiated.
Note: “Home to Switch and Marker” in the same homing command is not
supported.
Home to Switch
To home to a switch, the following sequence of events occurs.
1. The values of the following parameters are used to begin the homing
routine:
• Parameter 1120 [Home Accel Time]
• Parameter 1121 [Home Decel Time]
• Parameter 1122 [Home Speed]
• Parameter 1123 [Home Position] (firmware v4.001 only)
• Bit 26 “Home Dir” of parameter 740 [Position Control]
• Bit 28 “Home Switch” of [Position Control] is set, capturing the
position.
2. Bit 24 “Find Home” of parameter 740 [Position Control] is set or a digital
input programmed for “Find Home” is on (v4.001).