Rockwell Automation 20D PowerFlex 700S AC Drives with Phase II Control Reference Manual - Manual (Page 96)

96 Rockwell Automation Publication PFLEX-RM003E-EN-E - January 2011
Chapter 1 Detailed Drive Operation
Position Loop - In Position
Detect The In Position Detection determines if parameter 769 [Position Error] is within
a user defined value. Parameter 769 [Position Error] is the result of parameter 747
[Position Cmmd] - parameter 762 [Position Fdbk].
Parameter 782 [In Posit BW] sets the absolute number of position counts that
parameter 769 [Position Error] must be within for parameter 741 [Position
Status] bit 10 “In Position” to turn on.
Parameter 783 [In Posit Dwell] sets a delay time in seconds that parameter 769
[Position Error] must be within parameter 782 [In Posit BW] before parameter
741 [Position Status] bit 10 “In Position” turns on.
Position Loop - Point to
Point General facts about the point to point position loop:
• Uses only parameter 768 [PositReg P Gain] for tuning. Parameter 770
[PositReg Integ] is not used in point to point mode.
• The number of position counts per revolution depends on the type of
feedback device used:
– When using an encoder for positioning, the drive uses quadrature
counts, i.e., 1024 encoder = 4096 counts per motor revolution.
– When using a Stegmann Hi-Resolution encoder, the drive counts
1048576 counts per revolution.
– When using a resolver, the drive counts 65536 counts per revolution.
• Speed regulator tuning directly affects the position loop performance. The
speed regulator should be tuned before the position loop.
• For best performance, positioning should be used with a dynamic brake or
regenerative system.
Overview
The point to point positioning feature gives the user the ability to position the
load without an external position controller. The point to point function of the
position loop moves from the current location to the commanded location then
holds that position until given a new reference or a stop command. The position
In Position Detect
769
782
783
741 10
In Posit BW
In Posit Dwell
Position Error
Position Status
(In Position)