How do you wire a compressor switch?

Take a wire from one of the line terminals L1 to one side of the contactor coil. Take another wire from the second line terminal L2 and put it to one side of a N.C. contact on the overload block. From the other side of the N.C. contact on the O/L block take a wire to the N.C. terminal on the pressure switch. From the other side of the N.C. contact on the pressure switch terminal connect the wire to the other side of the coil. This configuration will be using the same coil voltage on the contactor as that of the supply voltage.