Axis Wizard/Axis Properties - Conversion Tab Overview (AXIS_GENERIC_DRIVE, AXIS_SERVO_DRIVE)
Use this tab to view the Positioning Mode and configure the Feedback Resolution for an axis, of the tag types AXIS_SERVO, AXIS_SERVO_DRIVE and AXIS_VIRTUAL.
When a parameter transitions to a read-only state, any pending changes to parameter values are lost, and the parameter reverts to the most recently saved parameter value.
When multiple workstations connect to the same controller using the Logix Designer application and invoke the Axis Wizard or Axis Properties dialog, the firmware allows only the first workstation to make any changes to axis attributes. The second workstation switches to a Read-Only mode, indicated in the title bar, so that you may view the changes from that workstation, but not edit them.
Parameters
Positioning Mode
This parameter is not editable for an axis of the data type AXIS_CONSUMED. Instead, this value is set in and taken from a producing axis in a networked Logix processor. The values that can be passed are:
- Linear- provides a maximum total linear travel of 1 billion feedback counts. With this mode, the unwind feature is disabled and you can limit the linear travel distance traveled by the axis by specifying the positive and negative travel limits for the axis.TIP: Only Linear is valid with a feedback type of LDT.
- Rotary- enables the rotary unwind capability of the axis. This feature provides infinite position range by unwinding the axis position whenever the axis moves through a complete unwind distance. The number of encoder counts per unwind of the axis is specified by the Position Unwind parameter.
Conversion Constant
Type the number of feedback counts per position unit. This conversion - or "K" - constant allows axis position to be displayed, and motion to be programmed, in the position units set in the Units tab. The conversion constant is used to convert axis position units into feedback counts and vice versa.
TIP:
For axes of the type AXIS_SERVO_DRIVE, the label will indicate the number of counts per motor revolution, as set in the Drive Resolution field of the Drive tab.
TIP:
For LDT Feedback Types, you can calculate the Conversion Constant value by clicking on the Calculate button on the Feedback page.
Position Unwind
This parameter is not editable for an axis of the data type AXIS_CONSUMED. Instead, this value is set in and taken from a producing axis in a networked Logix processor. For a Rotary axis, this value represents the distance (in feedback counts) used to perform automatic electronic unwind. Electronic unwind allows infinite position range for rotary axes by subtracting the unwind distance from both the actual and command position, every time the axis travels the unwind distance.
TIP:
For axes of the type AXIS_SERVO_DRIVE:
- when you save an edited Conversion Constant or a Drive Resolution value, a message box appears, asking you if you want the controller to automatically recalculate certain attribute settings. (Refer to Conversion Constant and Drive Resolution Attributes.)
- the label will indicate the number of counts per motor revolution, as set in the Drive Resolution field of the Drive tab.
Provide Feedback