I can see this with intermittent problems, but I have to ask, contacts in what, the encoder (I assume encoder since you say in the case)? If so, why not just replace the encoder, not a hard job, and not an expensive item, and then send the encoder back through WPC and let BW do the testing in house.
This at least does not trouble the customer.
If BW finds this is a problem, then they correct the issue in house, and any new encoders installed at the plant or in service should have nice clean contacts.
I would have hoped that with the number already replaced, BW would have been able to confirm this in house. Before anything is said, I know, during the removal and return shipment, particles can move. However, as with the old infamous Stanadyne injector used on the diesel, if the case is opened in a clean room, the specs will show.
Just my opinion, but that type of feedback is not my job anymore
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