Field help (WSTV) 

Use this field to identify the production resource that is to be used for the selected operations. This work center replaces the main (principal) work center for the operations.

Type in, or select from the Work Centers table the code of the resource to be used for the operations. It can be a machine, labor or subcontract work center.

If you define a work center of type 'subcontracting', the Subcontract code (field SCOCOD) is set to 'Structural' and the operation is automatically subcontracted. The subcontract operations are managed using the lead time defined in the subcontract product record. Subcontract operation times are not used by the scheduling.

To generate a temporary (or ad hoc) subcontract operation enter an internal work center as the main work center and the subcontract work center using a temporary subcontracting code. During the creation of a work order scheduling is carried out by priority on the main (workshop) work center. You can replace this work center with the subcontract work center if the operation is subsequently subcontracted.