Sudhir, This is an expected behavior with strictly typedef ring constants. Instead of menu rings, you will want to use enums. A Strict typedef keeps its cosmetic information on the front panel but not on the Block Diagram. The type of the ring does not depend upon its strings - like it does with enums.
See a similar post on this topic bellow: <a href="http://exchange.ni.com/servlet/ProcessRequest?RHIVEID=101&RPAGEID=135&HOID=50650000000800000016B20000&UCATEGORY_0=_49_%24_6_&UCATEGORY_S=0";>Strict Type Def with Menu Ring does not automatically update linked constants</a><br> Zvezdana S. National Instruments
