Mean time between failure

[Byron Sonnier]

Hello,

 

I'm attempting create a Mean time between failure statistic and running into a roadblock with creating calculated column in Spotfire. In excel version the calculation is =IF(Failure>0,(Hours/Failure),(Hours). In SPotfire calculated column i used the followingIf([MOTOR_FAILURE]>0,[D/C_HOURS] / [MOTOR_FAILURE],[D/C_HOURS]). For some reason when i do the math manually it is always off. any help would be great!!

[Fabian Duerr]

Sorry, I can't open your dxp file because it's a 10.x version. But I checked your excel and I'm getting confused because the column names are different from your expression above. Also there are strange records in D/C_HOURS like 80.00 / 88.00 which is an conflict to the remaining records. Maybe you can update you excel file also with an expected result.

[Byron Sonnier]

Thanks for getting back to me! I have attached the Exel with a column Motor MTBF Rev1 it contans the formula I'm attempting to place in Spotfire calculated columns to get the Mean time between failures 

 

=IF (Failures>0,(D_C Hours/Failures),(D_C Hours))

[Byron Sonnier]

Thanks for getting back to me! I have attached the Exel with a column Motor MTBF Rev1 it contans the formula I'm attempting to place in Spotfire calculated columns to get the Mean time between failures

=IF (Failures>0,(D_C Hours/Failures),(D_C Hours))

Screenshot 2020-10-25 MTBFGrand total MTBF should be 1,331.6

[Fabian Duerr]

Your column MOTOR_FAILURE is either 1 or NULL. So in Excel and in Spotfire you will always return your column D/C_HOURS with your IF statement. Either you return it directly or return it by dividing by 1. 

 

 

Do I still miss your point

 

Can you post a screenshot of your dxp file I can't open 10.x files...