Set Analysis based on the Sum of a field

[johnmccdwc]

HI Guys

I am working with a data collection system and want to calculate actual grinding time for a mill.  The data is collected every 15 minutes and if the weight of raw material is greater than zero a field called MatFeed is set to 1 during data load.  So if the plant is actually grinding MatFeed will be equal to 1.  Another field Runtime is also populated at data load and is based on electricity being above a threshold which shows the plant is running.  So I want to calculate the productive time while the plant is running (i.e. consuming electricity).  I am using =sum({<$(Sum(MatFeed)={">=1"}>}Runtime)) but am not getting the answer I expect.  I have attached a sample data set showing the calculation logic I want to achieve.  Any ideas? Thanks

[MK_QSL · Accepted solution]

=SUM({<TimeStamp = {"=SUM([Mat Feeding])>=1"}>}Runtime)

[johnmccdwc]

Thanks Manish