I think gentleman, the snooper has nailed it. Well lets start again. I wired my compressor to a switched fused spur and for what ever reason, it has cured my blowing fuse on start up problem AND the workshop is still in one piece.
Could be there's less resistance with the hard-wired setup, this means the motor starts more quickly with more back emf and less current. This is why compressors run off extension leads can blow fuses.
Some mains plugs are pretty poor, I have one that gets warm running a 1kW heater.