Control Techniques Epsilon EP-P, Reference Manual

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Epsilon EP-P Drive Reference Manual
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Revision A4 www.controltechniques.com
3 Setting Up Parameters
3.1 Status View
3.1.1 Status Online Tab
The Status Online tab (see Figure 34) is visible when online and consists of the Motor Position group, Motor Velocity group,
Control Loop group, Master Feedback group, and the Torque group.
Figure 34: Status View - Status Online Tab
3.1.2 Motor Position Group
Position Command
Position command (PosnCommand) is the commanded position generated by the drive based on the application. This
parameter does not take following error into account. See also Position Feedback and Following Error. Units are in user units.
Position Feedback
Feedback position (PosnFeedback) is the actual motor position in user units. PosnCommand minus the PosnFeedback is the
FollowingError.
Following Error
Following Error (FollowingError) is the difference between the PosnCommand and the PosnFeedback. It is positive when the
PosnCommand is greater than the PosnFeedback.
Encoder Position
Motor encoder position in encoder counts (PosnFeedbackInCounts). This position reflects the feedback position of the motor
and is not scaled into user units. This is a signed 32 bit value.
3.1.3 Motor Velocity Group
Velocity Command
The Velocity Command (VelCommand) is the velocity that the drive is commanding the motor to run at. This command is
generated by the drive velocity control loop and position loop. It is displayed in user units.
Velocity Feedback
The Velocity Feedback (VelFeedback) is the feedback (or actual) velocity. It is calculated using the change in position of the
motor encoder. It will always return the actual motor velocity - even in synchronized applications in which the master axis is
halted during a move.
3.1.4 Control Loop Group
Changing the Trajectory Update Rate can have a major effect on the performance of the servo system. A longer trajectory
update rate means that more time is available to process user programs. A shorter update rate means that the control loop is
updated more often and provides the most accurate performance. Without proper diagnostics, it can be impossible to tell how
much time is being consumed by the control loop update, and how much time is available to run user programs.
The Control Loop group of parameters on the Status Online tab shows the user how much time is available to run programs.
There are two parameters available to help with this. They are as follows: