Control Techniques Epsilon EP-P, Reference Manual

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Epsilon EP-P Drive Reference Manual
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Queue Size
This is the maximum number of elements that can be stored in the queue. If more pieces of data than this number are in the
queue at a time, then a Queue Overflow source will activate.
Queue Offset
The Queue Offset is the value that is added to the Queue Data and then compared to the selected source to determine when
the Queue Exit event activates. For instance, if the source in selected source is set to Feedback Position, and the Queue
Offset is set to 10, and the user puts the value 5 into the queue, the Queue Exit source will activate when the Feedback
Position is greater than or equal to 5 + 10 or 15.
Full Level
The amount of data in the queue is constantly monitored and the Queue Full source will activate when the number of pieces of
data in the queue exceeds the Full Level parameter. This is only a flag and does not indicate a fault of any kind.
Source
The Source determines which parameter the sum of the Queue Data and Queue Offset are compared to in order to activate
the Queue Exit function. If set to FeedBackPosn (Position Feedback), the sum of the data and offset are compared to the
Position Feedback parameter. If set to MasterPosn (Master Position), then the sum is compared to the Master Feedback
Position parameter, and if set to CommandPosn (Command Position), then the sum is compared to the Motor Commanded
Position.
Name
You can assign a descriptive name to each queue, making the setup easier to follow. The length of the text string is limited by
the column width with a maximum of 12 characters. Simply double click on the Name field of any queue’s line to assign a
name to it.
Number of Queue Units
This selects the number of Queues available. Maximum of eight.
3.21.1 Queue Sources and Destinations
Sources
Queue Exit
This source activates when the Comparitor Select parameter is greater to or equal to the sum of the data entered into the
queue, and the queue offset.
Queue Empty
This source is active if no data is stored in the queue. It will become inactive when the first piece of data is loaded into the
queue and remain inactive until all data has been removed from the queue.
Queue Full
The Queue Full source will activate if the number of pieces of data in the queue equals or exceeds the Full Level parameter.
The source will deactivate when the number of pieces of data in the queue is less than the Full Level.
Queue Overflow
This source activates when there is no more room in the queue to store data. The maximum number of pieces of data is
determined by the Queue Size parameter.
Destinations
Queue Clear
This destination automatically clears all of the data out of the queue. The cleared data is not saved and there is no way to
recover the cleared data. This is typically activated on power-up of the system to make sure no old data remains in the queue.
Queue Compare Enable
The Compare Enable causes the comparitor internal to the queue to function. If the Compare Enable is inactive, then the
Queue Exit source will never activate. If activated, then the Queue Exit source will activate when the Queue Data plus the
Queue Offset is greater than or equal to the Comparitor Select parameter.
To fully understand the operation of the queue, the following diagram has a more detailed view of the Queue object.