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Accelnet & Stepnet Plus Panels User Guide
16-01339 Rev 07
P
OSITION
M
ODE AND
P
OSITION
L
OOP
P
OSITION
L
OOP
D
IAGRAM
The drive receives position commands from the digital or analog command inputs, over the CAN interface or
serial bus, or from the CVM Control Program. When using digital or analog inputs, the drive's internal trajectory
generator calculates a trapezoidal motion profile based on trajectory limit parameters. When using the CAN
bus, serial bus, or CVM Control Program, a trapezoidal or S-curve profile can be programmed. The trajectory
generator updates the calculated profile in real time as position commands are received.
The output of the generator is an instantaneous position command (limited position). In addition, values for the
instantaneous profile velocity and acceleration are generated. These signals, along with the actual position
feedback, are processed by the position loop to generate a velocity command.
To bypass the trajectory generator while in digital or analog position modes, set the maximum acceleration to
zero. The only limits in effect will now be the velocity loop velocity limit and the current limits. (Note that leaving
the maximum acceleration set to zero will prevent other position modes from operating correctly.)
The following diagram summarizes the position loop.