Control Techniques Epsilon EP-P, Reference Manual

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Epsilon EP-P Drive Reference Manual
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width with a maximum of 12 characters. Simply double click on the Name field of any capture’s line to assign a name to it.
Capture Number
This parameter defines the number of Capture objects available. Maximum is eight.
Captured Data
The data that is acquired by the position capture is available to be used as variables in a program. The four parameters can
be accessed as follows:
Capture.#.CapturedTime
The time, in microseconds, from a free-running 32-bit binary counter at which CaptureTriggered activated.
Capture.#.CapturedPositionCommand
The command position, in user units, at the time when CaptureTriggered activated.
Capture.#.CapturedPositionFeedback
The feedback position, in user units, at the time when CaptureTriggered activated.
Capture.#.CapturedMasterPostion
The master axis feedback position, in master axis distance units, at the time when CaptureTriggered activated.
The captured data remains in these parameters until the capture component is reset and CaptureActivate is activated. When
the capture component is reset and CaptureActivate is activated, the data related to the previous capture will be over-written
by the most recent capture data.
Figure 62: Capture Timing Diagram
Figure 62 is a timing diagram that shows how the different capture related sources and destinations function. The three
numbers located on the diagram are associated to the following three notes respectively:
1. The CaptureActivate has no effect when the CaptureTriggered is active. CaptureActivate is ignored until the
capture component has been reset.
2. When CaptureEnable is deactivated, CaptureTriggered is deactivated, and the capture component is
automatically reset. The captured data is retained until the capture component is re-enabled and
CaptureActivate is activated.
3. CaptureActivate has no effect while the capture component is not enabled.
Assignments that Automatically Use Position Capture
Certain assignments (Sources or Destinations) automatically generate position capture data internally without using the
capture component. This data is used by the drive, but is not directly available to the user like the capture component data.
Following is a list of assignments that automatically generate or use captured data.
Sources that generate capture data:
Drive Inputs 1-8 – The Epsilon EP-P drive Inputs 1-8 are constantly monitored by the processor, and when activated will
automatically capture related data. The processor controls all resetting requirements. The capture only occurs on the rising
edge of an input. When the input is activated, the captured data will automatically be passed to the destination that it is
assigned to. The destination may then use the captured data to accurately initiate motion (if it is a motion-related destination).
Motor Encoder Marker – The rising edge of the motor encoder marker pulse will automatically capture data. This will allow
the user to accurately initiate motion on the rising edge of the motor encoder marker pulse. The falling edge of the marker
pulse does not capture data.
Master Encoder Marker – The rising edge of the master encoder marker pulse will automatically capture data. This allows
the user to accurately initiate motion on the rising edge of the master encoder marker pulse. The falling edge of the marker
pulse does not capture data.
Index/Jog Command Complete – Activation of the command complete signal at the end of indexes and jogs will
automatically capture data. A subsequent index, jog, or dwell can then use the captured data to start itself extremely accurate
at the end of the previous motion.
Index/Jog At Velocity – Activation of the command complete signal at the end of indexes and jogs will automatically capture