to fig2 three phase ac electric power 50 may be delivered to compressor 12 to operate an electric motor sm 32 and cm 30 may receive low voltage power from one of the phases of electric power 50 delivered to compressor 12 for example a transformer 49 may convert electric power 51 from one of the phases to a lower voltage for delivery to sm 32 and cm 30 in this way sm 32 and cm 30 may operate on single phase ac electric power at a lower voltage than electric power 50 delivered to compressor 12 for example electric power delivered to sm 32 and cm 30 may be 24v ac when low voltage power for example 24 v ac is used to power cm 30 and sm 32 lower voltage rated components such as lower voltage wiring connections may be used cm 30 may control operation of the compressor 12 based on data received from sm 32 based on other compressor and refrigeration system data received from other compressor and refrigeration system sensors and based on communication with a system controller 34 for example cm 30 may be a protection and control system of the type disclosed in assignee 39 s commonly owned u s patent.