Valor Process Preparation
iFlex - Uncontrolled feeder replacement and / or duplication of it
2023-09-11T07:07:19.000-0400
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Summary
Even when feeders are manually assigned and fixed some are duplicated and or moved.
Original positions are in the feeder setup but are not used. In configuration the duplication is also set to none.
Details
Answer Valor Process Preparation cannot control this behavior because it is changed by the KnS Optimizer. Data is send to the KnS optimizer and results are returned.
How to identify
Warnings seen in the optimizer log files.
Yellow: GetFeasibility Warnings Part "2454665" was duplicated beyond its inventory limit, for mandatory duplications (limit: "1", actual part count: "2"). Duplications may be mandatory for pre-assignments, for multiple INDEPENDENT mode orders on multiple lanes and for medium-sized boards. CORRECTIVE ACTION: Review part inventories, pre-assignments, dual lane mode and board lengths.
Explanation by KnS.
The optimizer indeed ignores (increases) the part inventory limit is some cases:
In case of pre-assignments. Rationale: if more parts are pre-assigned than listed in the inventory we assume that the pre-assignments are leading.
In case of dual lane and using independent mode. Customer doesn’t use dual lane so this can’t be the reason.
In case of medium size boards (290 – 520 mm) and using 2-step (reducedFeederduplication is false). Rationale for this is that T modules do not have full board reach for these board lengths. If the iFlex machine has no H1 (so only T modules) the optimizer will increase the inventory from 1 to 2 enabling duplication. This only occurs if needed for feasibility. I.e. if a single T2 robot is not able to reach all placements. Rationale for this is that we found it very annoying to generate an error and force the operator to manually increase the inventory for all parts which would be infeasible otherwise.
Looking at the third case you can also enable 3-stop (by setting the project setting reducedFeederDuplication to true). If enabled the T modules will add an additional board stop which enables a single T2 robot to do all the placements. With a possible output penalty.
From the optimizer only warnings are returned to Process Preparation which are not shown. A hint can be seen by opening the Session Status Report after running the Optimization. This shows the warnings