Glossary

# MTBF (Mean Time Between Failures)

Mean error-free operating time, mean time between failures: it is a significant reliability parameter for the MES environment which is derived from the reciprocal of the failure rate. The mean time interval between two failures is given for replicable objects. It applies to units that are being repaired. The definition according to IEC-60050-191 is: the expected value of the operating time between two successive failures.