Question:
What effects does the setting of an angle offset have on the input CDATA-OFFS-XIN?
Answer:
With reference to the preselected master value position (x-axis) of the electronic cam the user can set an angular displacement at function block input CDATA-OFFS-XIN in the form of an x-offset. This kind of offset is required e. g. in applications with several cams, which are operated in the network of an electrical shaft and phase shifted against each other on this shaft.
Then the electrical shaft is represented by the coupling of the master value position at the input CDATA-XIN (absolute master value coupling) of the connected drives. The input CDATA-OFFS-XIN has an effect only when the absolute master value coupling (C1332/000 = 1) has been selected.
The setting range for the angle offset is generally related to the curve pulse of the x-axis, this means the absolute incremental master value at CDATA-XIN and the added / subtracted offset at CDATA-OFFS-XIN together must be within the double length of the x-axis of the used motion profile.
Example:
The x-clocking time of a curve is 65536 increments. The setting range for the master value (CDATA-XIN) and the angle offset (CDATA-OFFS-XIN) in addition must always be within the double x-clocking time of the applied cam, in this case between +/- 2 * 65536 increments = +/- 131072 increments.
The clocking time of the used curve can be seen in the function block configuration at the output CDATA-ACTLEN or in code C1315/x for the corresponding curve.
When this setting range is quit at the input CDATA-OFFS-XIN inside the FB CDATA an angle offset limitation is executed for the current curve pulse. At cycle transition (CDATA-X0) the limitation can lead to a position jump by the difference to the double clocking time. If the sum of angle offset and master value is too high for a resulting or valid position value within the following pulse, the master value processing stops in CDATA, and at CDATA-NOUT a zero-setpoint (speed 0) is given.
Therefore, in practice the set angle offset should be at CDATA-OFFS-XIN in the setting range of +/- one x-clocking time.
