Control Techniques Epsilon EP-P, Reference Manual

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Epsilon EP-P Drive Reference Manual
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www.controltechniques.com Revision: A4
The drive provides Feedforward compensation to correct for these delays introduced by the filter.
The user may set the number of filter samples to be used to “smooth” the master encoder velocity. The more samples used by the filter, the
smoother the master velocity signal, however, the more positional delay introduced by the filter. This means that more filtering will cause more
position error between master and follower. Feedforward is used in conjunction with the filter to provide accurate positioning performance while
still maintaining smooth motion.
The following table can be used to best determine the proper filter settings for your application.
Filter parameters cannot be changed using the “Update to RAM” feature. Changes must be fully downloaded before taking effect.
The gray box in the table above denotes the default setting for the master filter parameters.
Enable Check Box
The Enable check box is used to turn on or turn off the Master Position Filter. If selected, the filter is turned on (active) and the user must select
the number of samples used by the filter. If clear, the filter is not used.
Samples
Defines the number of samples used by the filter to smooth the master signal. Increasing the number of samples increases smoothness, but
also increases lag. See Filter table above to select proper setting.
Enable Feedforward Check Box
The Enable Feedforward check box is used to turn on or turn off feedforward. If selected, feedforward is active. If the check box is clear,
feedforward is not used.
3.8 Virtual Master View
The Virtual Master View is used to create a simulated encoder output. It generates an encoder stream of counts without the actual operation of
a motor. This count can be used by the drive itself as an input to the Master Source (MasterAxis.Source). It can also be transmitted to other
drives through the Sync Encoder Output connector and into their Master Sync Input connector.
Figure 43: Virtual Master View Enabled
3.8.1 Enable Virtual Master Check Box
Enable Virtual Master check box (VirtualMaster.VirtualMasterEnable) by default is clear. Select the check box to enable the virtual master
Feedforward OFF Feedforward ON
# of
Sample
s
Disabled
One update of phase shift
(not velocity dependent)
No Filtering
No delay,
No Filtering
4
Small Lag (function of
speed),
Low Filtering
Poor at low speed,
Low Filtering
8
Medium Lag (function of
speed),
Medium Filtering
Good at low speed,
Medium Filtering
16
Large Lag (function of
speed),
High Filtering
Best at low speeds,
High Filtering
Smoother
Increasing
Lag with FF
Off
Reduced Lag