Service tax credit

Hi,

In my factory construction project, I am paying Service Tax to my designers, consultants. Now as per CENVAT rule can I get the S.T. tax rebate when I start my factory starts it's production in future and I have to pay Excise duty?

I have got an idea that I can get the credit of only tax paid in production equipments (Excise / VAT etc.), not on the taxes involved during design stage or construction works (WCT).

Thanks 

DP Das