Relation Between Dummy Profit Center and Posting Keys.

Question

Hello Gurus,
It will be a valuable feed back for below mentioned Scenario.
One of our client is on SAP Version 4.7 and New GL is not activated. In COCD one Customer Invoice entry is booked as below.
PK     Account           Amount      Profit Center
01     SURXXX1            100.00         ABCD
50     REVENUE A/c      50.00         ABCD
50     ENT TAX               20.00         ABCD
50     SERVICE TAX       30.00         ABCD
After running t codes 1KEK, F.5D, and KE5T for customer line item system picks same profit center as mentioned in other line items i.e ABCD.
But when we reverse the above document system picks DUMMY Profit center instead of ABCD. 
PK     Account           Amount      Profit Center
12     SURXXX1            100.00         DUMMY
40     REVENUE A/c      50.00         ABCD
40     ENT TAX               20.00         ABCD
40     SERVICE TAX       30.00         ABCD
Basically we have checked field status variant for Posting Key 01 and 12 in which Profit Center field is Required and field status for profit center for reconciliation account is also required. This is unusual behavior which we are facing right now.
Regards,
Ajinkya Ahire 

Answer 1

Profit Center :
A profit center is a management-oriented organizational unit used for internal controlling purposes. Dividing your company up into profit centers allows you to analyze areas of responsibility and to delegate responsibility to decentralized units, thus treating them as "companies within the company". EC-PCA lets you set up your profit centers according to product (product lines, divisions), geographical areas (regions, offices or production sites) or function (production, sales).
Profit Center Accounting (PCA) allows you to calculate internal measurements of profitability. This internal view of profitability, then, reflects the success of a given profit center at meeting the profitability goal for which it was given responsibility.
Cost Center :
The cost center is an organizational unit in a controlling area. Cost centers can be defined according to several different design approaches. A typical approach could be for an enterprise to define a cost center for each low-level organizational unit that has responsibility for managing costs. As costs are incurred, they are assigned or posted to the appropriate cost center. These costs could include payroll costs, rent and utility costs, or any other costs assignable to a given cost center.
Each cost center is assigned to a category, e.g. Administration cost center, production cost center, etc. Each cost center master record has a field for the name of the person responsible for the cost center.
For detailed information go thru the below article
https://wiki.sdn.sap.com/wiki/display/ERPFI/BasicConceptsof+Controlling
Hope this helps.
Cheers,
Srinath.