Passing Control Limits into SPC Charts - Part 2

[Former Member]

I'm able to pass control limits (LCL, CL, UCL) into my SPC chart but it's not woking quite as I expected. If I look at the raw data detail, I see:

Date Prod LCL Mean UCL

Oct-2005 298265 100000 150000 200000

Feb-2006 298171 120000 150000 160000

Aug-2006 198144 75000 125000 175000

Mar-2007 2144 40000 100000 160000

Aug-2007 144 40000 100000 160000

I would have assumed that the LCL, Mean, UCL from the first row (100000, 150000, 200000) would "take effect" on that row's date (10/2005) and continue for all FUTURE data points until the first subsequent date that had a different LCL, Mean, UCL value(s) but, looking at the SPC chart, it seems whenever there is a change in the LCL, Mean, UCL, the values apply to data points PREVIOUS to that row's date.

I'd like users to enter LCL, Mean and UCL data into a control limits database whenever there is a change in the values that should be applied to future points but I don't think that's the way the SPCChart template works.

Any thoughts?

David

[Former Member]

Thanks, Jeremy. Let me know if you need anything else.

David

[jcgood25]

David,

In order to trigger the developer workflow and possible SAP note fix, please enter this issue into the customer support portal for further technical support investigation. I haven't seen anything entered into the system in regards to this problem.

Regards,

Jeremy

[Former Member]

Jeremy,

We just submitted this issue into the customer support portal - it was logged as message # 0000990687/2007 'XMII - iSPC Chart Control Limits display issue'

Thanks,

David

[jcgood25]

Thanks Dave - I can see the message and have attached some of the pieces that can be used to replicate it to facilitate the support/dev investigation.

Go ahead and close out this thread and we'll let the message handling process in support take over.

Regards,

Jeremy

[jcgood25]

David,

If you need a simple model for the data store of your user defined Control Limits, along with their effective dates, you can use the ControlLimitDetail table that is part of the QualityPortal database schema. The Comments and SuppressedDataPoints tables are already used by the iSPCChart applet when the user interacts with the right-click menu for recording point comments and suppressing data points, so this table (along with SpecificationLimitDetail) can be leveraged if you need a place to put them.

I emulated your situation here on my 11.5.3 system - it does seem to project the dotted lines backwards from the record based association, so you may have stumbled onto a problem with the chart. Please enter this into the customer support portal so that it can be properly addressed.

Regards,

Jeremy

[Former Member]

Jeremy - doesn't the query need to return only the date + the three limits, as opposed to the "extra" column (Prod) in the example query?

[jcgood25]

Prod is the ValueColumn, the others are used for the Extended Data Mapping to have the 'row' based limits - he's not using the old query template approach to lookup the limits in conjunction with the raw data query.