MTTR/ MTBR REPORT
WHILE USING T-CODE "MCJB"; I NOTICED THAT FIRST BREAKDOWN IN A MONTH IS NOT TAKEN INTO CONSIDERATION WHILE CALCULATING "TOTAL LENGTH OF BREAK DOWN".
I UNDERSTOOD WHY ITS NOT TAKEN IN ACCOUNT IN CASE OF MTBR, BUT I DIDNT UNDERSTOOD THAT WHY FIRST BREAKDOWN IS NOT CONSIDERD IN CALCULATING MTTR.
REFER ATTACHED IMAGE
FIRST DOWN TIME OF DURATION 8.84 HR IS NOT TAKEN INTO ACCOUNT
Jogeswara Rao K replied
The reason is already mentioned in the picture you posted. When the Start-up date of the Equipment Master is not filled (Filed shown in the picture below IE02 ), then it happens. In this case the first Breakdown Date is treated as the Start-up date, so consumed that way.
Please go through this document for other details in this regard. MTTR / MTBR / Breakdown Analysis Information System Overview