An air compressor takes about 15 to 20 minutes from an empty state. There are some air compressors that take 2-5 minutes. The time for filing an air compressor depends on the CFM. The higher the CFM, the quicker to pump the air. A larger tank shall need more air to compress and to fill it. A single-stage air compressor will run at an optimum of 125 psi. This is because it does not have the capability beyond this to operate efficiently. It will shut off. Anything over 10 minutes and 135 to 140 psi, then cool it and try again as it has hanged there.