Grinding is not the route to take. You want to shot blast the floor , this will scabble the surface and leave it ready for epoxy coating .
You can rent a shot blast machine from a good flooring supply , just plug it in go .
a conductor will have a max temperature rating . A termination will also have a temp rating , in most cases for residential it is 60 * C . the amp rating for the conductor must be taken from the 60* column .
reset the circuit breaker in the breaker panel serving the compressor.
Be sure to firmly push the handle to off before turning on , then check voltage across L1 and L2 to verify 240 volts