IME, Compressor Rating normally cannot run (siam) one. especially true for reknown compressors in the market from North America, Western Europe and Japan.
the thing which comes into much discrimination is when the cooling capcity of the system comes into play. as cooling capacity is judged upon by the cooling power of the system as a whole and not the compressor itself. many things comes into consideration. the cooling core, size of tubing, refrigerant amt (superheat), size of condenser, blower fan power, etc.
much depends on the ambient temperature and the load given to work too. diff countries, diff atmosphere, diff humidity, diff temp.
juz me 2 cents.