User guide
Operational Theory Xenus XTL User Guide
28 Copley Controls Corp.
2.11: Position and Velocity Errors
2.11.1: Error-Handling Methods
In position mode, any difference between the limited position output of the trajectory generator
and the actual motor position is a position error. The amplifier’s position loop uses complementary
methods for handling position errors: following error fault, following error warning, and a position-
tracking window.
Likewise, in velocity or position mode, any difference between the limited velocity command and
actual velocity is a velocity error. The amplifier’s velocity loop uses a velocity tracking window
method to handle velocity errors. (There is no velocity error fault.)
2.11.2: Following Error Faults
When the position error reaches the programmed fault threshold, the amplifier immediately faults.
(The following error fault can be disabled.)
For detailed information, see Following Error Fault Details (p. 29).
2.11.3: Following Error Warnings
When the position error reaches the programmed warning threshold, the amplifier immediately
sets the following error warning bit in the status word. This bit can be read over the CAN network.
It can also be used to activate a digital output.
2.11.4: Position and Velocity Tracking Windows
When the position error exceeds the programmed tracking window value, a status word bit is set.
The bit is not reset until the position error remains within the tracking window for the programmed
tracking time.
A similar method is used to handle velocity errors.
For detailed information, see Tracking Window Details (p. 30).