Periodic Cams

A cam can be run repeatedly when the Periodic input of the MC_CamTableSelect function block is set to TRUE. Then the cam is restarted automatically after reaching the end position. If this input is FALSE, then the EndOfProfile output variable of the MC_CamIn function block is set to TRUE when the end position of the master is reached. The slave pauses at its current position.

Note that the cam activity does not stop after leaving the master value range. When the master drive re-enters the master value range, the slave drive follows the cam plate again.

Behavior in the case of Slave.EndPosition <> Slave.StartPosition: The function block MC_CamIn calculates an internal offset at the end of a period. In the subsequent period, the cam is shifted by this offset so that it continues at the current position of the slave and consequently prevents jumps.

For a periodic cam, you can activate the Smooth transition option in the cam properties. This is used for preventing jumps from occurring when transitioning from one period to another. Then the slave has the same velocity and acceleration at the end position as at the start position. The period and feed are measured in the units of slave scaling. Even if you do not select the Smooth transition option, the cam can be operated continuously. In this case, your task is to make sure the consistency of the transitions are satisfied to a sufficient degree.