95' 1/2 ton truck A/C problems

My compressor locked up and threw the belt off! Purchased a new compressor, Accum. and orfice tube. Evacuated system put everything back properly(its not rocket science) Charged system. Now the cluch wont kick on. I have no power to the A/c connection. Checked fuses and the a/c realy and have power to both. What could have caused this to happen?!:shakehead