Re: MTBF (Mean Time Between Failures) Calculation
The other part of your OEE is the Mean Time To Repair. When you decide to start the counter on either of them is something that should be understood by Maintenance, Production and yourself.
Normally, MTBF is from "start-up" to fail, MTTR may start at Maintenance notification and run until they return the machine to production (after prove out of the repair). I have seen some engineers track MTTR until the "Okay to Run" was issued from QA. I have also seen where scheduled downtime was not computed in MTBF because the machine wasn't running.
Decide what data is going to help. When to start or stop isn't the main issue. Getting data and being able to use it to make you better is.
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