Rockwell Automation Publication MOTION-RM003I-EN-P - February 2018 227
SLAT Time Delay
Time delay after SLAT Set Point is reached to switch from Speed control to Min/
Max control.
Usage Access T Data
Type
Default Min Max Semantics of Values
Optional - V Set/SSV
REAL - - - Seconds
Time delay after SLAT Set Point is reached to switch from Speed control to Min/
Max control.
SLAT Min Speed/Torque Mode
In SLAT Min Speed/Torque mode (SLAT Configuration = 1) the drive defaults
to the state with speed control off (leftmost state) shown in the figure below. In
this state, the torque reference is the minimum, or Min function, of the Velocity
Loop Output or the Torque Command.
Min Mode
When used for SLAT control, an application dependent Velocity Command is
applied to the drive. When the motor's speed is mechanically limited, this
reference is at a level that results in saturation of the velocity loop output. In this
state, the 'Min' select operation selects the smaller Torque Command value. The
Velocity Error is positive in value equal to the Velocity Command.
If the mechanical speed limitation is removed (example web break), the motor
accelerates and the Velocity Error becomes negative when the motor speed exceeds
the Velocity Command. At this time, an automatic transition to speed control
occurs and the Velocity Loop Output is selected as the Torque Reference,
regardless of the value of the Torque Command. Coincident with the transition
into speed control, a preset operation will occur within the velocity loop. This
preset will force the velocity loop integrator to match the internal torque reference
value, at the time of the mode transition.
In Min mode the drive remains in speed control until the Velocity Error exceeds
the configured SLAT Set-point attribute value for a period of time given by the
SLAT Time Delay attribute. When these two conditions are met, speed control is
turned off and the 'Min' select operation becomes active. This condition would
occur if the mechanical constraint was restored.