Thanks for great solution.In drawing mode,
right click and hold in empty space anywhere> properties> drawing options> change required parameters in dimension group
Save this .dtl file in your system and give path of that file in your config.pro in parameter--> drawing_setup_file
.dtl file contains set of drawing settings.You can create multiple .dtl files with perticular settings (like one for mm, one for inch, one for dual....)
and load perticular file when required.