Wright Williams & KellyFactory Explorer® v2.2 Technical Alert #2 Summary: Factory Explorer®'s model validation code does not flag as an error the situation where a rework loop ends with less than a 100% goto. In the simulation, this can cause a rework lot to exit prematurely from a rework loop and continue through the process flow. Factory Explorer® halts with an internal error when such a lot attempts to exit from the process flow, but this error can be hard to trace back to the original cause. This model validation error is detected with Factory Explorer® v2.3. Details: In Factory Explorer®, every rework loop must end with a 100% goto to a step at or above the original rework step. Factory Explorer® 2.2, however, did not check to ensure that this goto actually specified 100%. If less than 100% was specified, some rework lots could exit prematurely from the rework loop and continue on through the process flow. When a rework lot attempts to exit the process flow, Factory Explorer® will halt with an internal error "Lot is rework child or parent -- error in routing file", as this situation should never occur. Tracing this error back to its cause, however, could be difficult. Workaround: Check that all rework loops end with 100% goto's.
Techalert fx2-9707
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