Re: Thermal O/L Relay setting


NEC 430.32 gives the rules for sizing motor overloads. You must either determine the service factor which should be on the nameplate or determine the marked temperature rise also on the nameplate.


Motors with a marked service factor 1.15 or greater                                           125%

Motors with a marked temperature rise 40'C or less                                            125%

All other motors                                                                                                  115%