An instance of this Function Block type provides the logic for using a rotary solenoid to transfer a ring from an upper chute to a lower chute when a ring is not present in the lower chute. Its operation is defined by the Execution Control Chart (ECC) and Ladder Diagram (LD) REQ algorithm shown above.

The input and output variables of this function block type correspond to the similarly named outputs and inputs, respectively, of the Sortation/Inspection testbed.

See the TESTBED_MVCL system configuration for an example of the use of an instance of this type.