Rockwell Automation 20D PowerFlex 700S AC Drives with Phase II Control Reference Manual - Manual (Page 168)

168 Rockwell Automation Publication PFLEX-RM003E-EN-E - January 2011
Chapter 1 Detailed Drive Operation
Paper Winder Application Example:
The drive is set for SLAT minimum mode, so that the drive normally runs in
torque mode and follows parameter 111 [Torque Ref1]. Torque reference 1
comes from an external controller and is approximately 60% of motor torque
during the snapshot (seen below). The speed reference, also from an external
controller, is set just above the speed feedback in order to saturate the speed
regulator while in torque mode. The following snapshot captures what occurs in
the drive during a break in the web.
SLAT Maximum Mode
In SLAT maximum mode, you would typically configure a speed reference that
forces the speed regulator into saturation (the speed reference is slightly below the
speed feedback). In this case the drive would follow the torque reference until
there was a breakage or slippage in the application.
In SLAT maximum mode, the drive will switch from torque mode to speed mode
when either one of the two following conditions occur:
• The output of the speed regulator becomes more than the torque
reference. This is the same condition that exists in maximum torque mode.
Or,