This function block may be used with the Cyclic Position function block to set the Zero position for the Internal Count and to empirically set the Cycle Length. The Set Cycle Zero and the Set Cycle Length functions may be separately enabled to control the behavior.

Usually, this function block is only used during initial commissioning of a cyclic positioning application; however, should the relationship between the encoder and the machine indices change in any way (e.g., the encoder being physically relocated), re-setting the Zero and Cycle Length will likely be required.

If desired, an external sensor such as a photo-eye or a proximity switch may be mounted on the machine and connected to the Set input to reset the Zero position every cycle to prevent long-term accumulated error due to mechanical variations.

The normal commissioning procedure would be as follows:

1. Enable both the Enable and Length Enable parameters.
2. Move the machine to the desired Zero Position (the location of the photo-eye or proximity switch. Ensure you mark this position on both the moving and stationary portions of the machine so it may be easily located when setting the Cycle Length.
3. Momentarily change the Set input to True to reset the Internal Count.
4. Move the machine through one entire cycle and position the machine so the two positioning marks re-align.
5. Re-assert the Set input to True to move the Internal Count into the Cycle Count register.
6. Disable the Length Enable parameter.
7. If there is no photo-eye or a proximity switch, Disable the Length Enable parameter.

• Available only in the dw2xx series products
• Requires library: Encoder Control (option -11)
• Requires: Single or Dual Encoder
• Firmware versions 0x2015 and later

If the Enable is Enabled, the rising-edge of the transition from False to True sets the Internal Count to zero. If both the Enable and the Length Enable are Enabled then the Cycle Length calibration procedure is begun and another false-to-true transition is required.

When Enabled, the rising-edge of the Set input resets the Internal Count to zero.

When Enabled, the first rising-edge of the Set input resets the Internal Count to zero while the second rising-edge of the Set input moves the Internal Count to the Cycle Length defining the cycle.