how to setup the default asset category to the fixed asset create from oracle payable invoice lines

how to setup the default asset category to the fixed asset create from oracle payable invoice   

This is the asset into FA from payable invoice lines and the category (asset category) is null in invoice lines or invoice distributions , After running the mass addition create program i can see the asset category in mass addition summary of fixed asset , and for every asset created from the payable invoice distribution is creating asset with the same category.

can you guys help me to find out the setup where i can disable the default category for the assets

Thanks in advance !!

Madhav.