PLS has On and Off points just like a global PLS, but the On and Off points are specified as an incremental distance from the start of the index, instead of absolute positions.
Each index has its own On and Off points, and the Index.#.PLSStatus is only updated when Index# is run. The direction of the PLS does not matter, the Index.#.PLSStatus will activate and deactivate the same incremental distance from the start of the index.
PLS On Point
This parameter is an incremental distance from the start position of the index, at which the PLS.#.Status will become active. It is an unsigned value in user units. The On Point must always be less than the Off Point.
PLS Off Point
This parameter is an incremental distance from the start position of the index, at which the PLS.#.Status will deactivate. It is an unsigned value in user units. The Off Point must always be greater than the On Point. If the Off Point is larger than the Distance parameter in an Incremental type of index, the PLS Status will never deactivate until the index is run again.
Example 1:
Index 0 is an Incremental index with a distance of 5 Revs. The PLS On Point is set to 1 Rev, and the PLS Off Point is set to 4 Revs. A home is completed, and Position Feedback is equal to 0.0 Revs.
If Index 0 is run, the Index.0.PLSStatus will activate when the feedback position reaches 1 Rev and remain active until feedback position reaches 4 Revs, and deactivate. At the end of Index 0, position feedback is equal to 5 Revs. If we initiate Index 0 again, Index.0.PLSStatus will activate 1 Rev into the index, or at 6 Revs. It will remain active until position feedback reaches 9 Revs, and deactivate. This index could be run over and over again, and Index.0.PLSStatus will activate 1 Rev from the starting position and deactivate 4 Revs from the starting position every time.
Example 2:
Index 1 is an Incremental index with a distance of
If Index 1 is run, the Index.1.PLSStatus will activate when the position feedback reaches
Index PLS's can be used on any type of an index.
If an index is so short (possible in the case of an absolute index) that it reaches the On Point, or incremental distance, into the index, but never reaches the Off Point, the Index.#.PLSStatus will remain active until the index is
run again.
Similarly, if the index is so short that it never reaches the On Point, the Index.#.PLSStatus will never activate.
Registration Parameters
The following parameters are only used if Registration is selected as the Index Type.
'Analog' or 'Sensor' Radio Buttons
Select one of these radio buttons to determine what signal will be used as your registration trigger.
If 'Sensor' is selected, a source must be assigned to the Index.#.SensorTrigger Typically a proximity sensor is wired to a hardware input, and therefore a module or drive input source is assigned to the Index.#.SensorTrigger, but any source can be used.
If 'Analog' is selected, one of the analog signals must be selected in the analog list box. Available selections are Analog In, Torque Command, or Torque Feedback. Then a comparison operator must be selected from the operator list box. Available selections are > (greater than) and < (less than). Last, an analog value must be entered for comparison.
Registration to Analog Input Value
If Analog In is selected, the value of the drive Analog Input is used as the registration signal.
When the value of the analog input reaches a value that satisfies the comparison operator, the sensor trigger will activate. Units for the registration value will match the units configured on the Analog Inputs screen when Analog In selected.
Registration Offset
The incremental distance the motor will travel after a valid registration sensor or analog limit value has been detected. This is a signed parameter; so if an index is travelling in the negative direction, the offset needs to be negative and continue in the same direction. If the registration offset is zero or less than the decel distance shown on the calculations tab, the motor will decelerate at the programmed rate and then back up to the specified offset distance from the trigger position.
Enable Registration Window
This check box enables (if checked) the Registration Sensor Valid Window. When active, only registration marks that occur inside the registration window are seen as valid.
Window Start
This parameter defines the start of the Registration Sensor Valid Window relative to start position of this index. This is an unsigned value and is relative only to starting position of this index. Index direction does not affect this parameter. The Registration Window Start position (or distance) should be less than the Registration Window End position.
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