Counting the Average Times of Alarms in a Process using Minitab

[timmywimmy]

Hi,

If I have, say, 8 rows of times as below:

1 01/05/2012 0:01:19 In Alarm
2 01/05/2012 0:01:58 Return To Normal
3 01/05/2012 0:02:19 In Alarm
4 01/05/2012 0:02:23 Return To Normal
5 01/05/2012 0:04:31 In Alarm
6 01/05/2012 0:05:22 Return To Normal
7 01/05/2012 0:06:02 In Alarm
8 01/05/2012 0:06:41 Return To Normal

(Row number, time/date, Alarm condition)

I need to find out the average time that an alarm is switched on for( the amount of time between "In alarm" and the next "Return To Normal")

If each "Return To Normal" follows its own "In Alarm" as above, how can I get Minitab to produce the average amount of time that the alarm is "In Alarm" for?

I have nearly 9000 rows of this data to average out!

[Steve Prevette]

It can be done quite easily in Excel spreadsheet, but not aware of how to do in Minitab.

[timmywimmy]

Thanks Steve, a clue as to how to do it in Excel would be greatly appreciated

[Steve Prevette]

In Reply to Parent Post by timmywimmy

Thanks Steve, a clue as to how to do it in Excel would be greatly appreciated

see attached

[timmywimmy]

That's really great Steve, thanks!

[wang1568]

C3 formula: When(LAG('Date-Time',1))
C4 formula: when(if(status="Return To Normal",ELAPSED('Date-Time'-'Lag 1 row'),MISS()))
C5 formula: when(MEAN(Elapsed))