Level 1 - Runs Up is checked for mean chart and size of the trend is 3.
Level 2 – For Second level the size of the trend should be greater than the first level of the trend size. If Runs Up is checked for mean chart and size of the trend is entered less than or equal to 3 then it will display the message ' Runs Up and Runs Down should be greater than 3', because in first level size of the trend is 3.
This is valid for all trends like Runs Down, Greater than Less than Mean/Range. In this application 2 levels are used. Depending upon the selection of levels trends are raised. E.g. In First level Runs Up is checked and size of the trend is 3. In Second level Runs Up is checked and size of the trend is 5.
Following two cases are explained depending upon the above example.
Case - 1
If last three consecutive samples are UP then trend will get raised as 'Runs up violated for mean chart at level 1 for parameter height’; Operator has not taken the corrective action for the same trend. Operator is dumping the reading and the next two samples are also up then trends will be raised as 'Runs up violated for mean chart at level 2 for parameter height' and then the login screen will come. Here only supervisor can login. Operator has to call up supervisor and after successful of supervisor login, it will show the corrective Action screen so here Supervisor has to take the corrective action for the same trend then only operator can continue to take the readings and here the trends will get reset.
Case - 2
If last three consecutive samples are UP then trend will get raised as 'Runs up violated for mean chart at level 1 for parameter height’; Operator has taken the corrective action for the same trend. Then the trends for it will get reset. Operator is dumping the reading and the next two samples are also up then Trends will not be raised as 'Runs up violated for mean chart at level 2 for parameter height' because the operator has already taken the corrective action at first level only. If the operator has taken the corrective action at first level only then second level trend will not be get raised.
Second level trends will get raised only when operator has not taken the corrective action at level one and the next two consecutive samples are up for mean i.e. depending upon the selection of the trend size.
First level trends have been raised and the operator has not taken the corrective action and the next consecutive sample is not runs up then the trends for up will be get reset.
Above cases are also valid for all the trends like Runs Down, Greater than Mean, Less Than Mean if the option is checked in Trend Settings.