The improved gearing of the helical speed reducer

A  motor reducer  should  be  selected  with  a  thermal  rating  that meets or exceeds the ACTUAL horsepower to be transmitted.  Synthetic oils increase the thermal rating, and may allow a  smaller  unit  to  be  selected.    The  larger  housings  and improved gearing, with the appropriate synthetic oil, make cooling fans unnecessary on the 380 series and smaller.  Cooling  fans  of the electric motors are  still  available  on  the  450  series  and larger.