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First Pass Yield

First Pass Yield

First Pass Yield

In an electronic assembly process where you assemble a product and then perform a functional test would you include assemblies that are redirected for rework based on visual inspection failures before they even make it to the functional test in your FPY percentage? Or only products that fail the functional test?

An example might be that an assembler notices a wire has come loose from its crimped connection during assembly so its redirected to rework to repair the crimp and then brought back into the assembly process and then passes functional test.. Should that rework be included in the first pass yield.. Assuming all products pass the function test (lets say a quantity of 10)..
Would you consider FPY as 100% or 90% due to the 1 requiring rework prior to function test.

RE: First Pass Yield

Personally, I would consider it a 90% case, as I think that calling it 100% obfuscates the fact that you did have a production defect. I'm not sure why you would separate the visual inspection from the actual test; it's all part of the same overall process.

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RE: First Pass Yield

Personally I agree also I just wanted to see how many others either do count it or don't count it as part of First Pass Yield..
Now we do collect numbers on how many products do need repair before final inspection but that number is just not included in the "FPY"..

Seems to me though that in this day and age "FPY" is supposed to be a "key indicator" of your quality rate through a process.. And I just don't see how a "key indicator" could be the same 100% for something that required no rework/all passed the functional test and then the same 100% where 1000 reworks were required to even get to the functional test..

Does anyone request FPY data from a contract manufacturer or anything as part of your vendor qualification program and accept the FPY as a true (and only) number of their quality rate.?

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