The single phase electric motor has been standardized in Brazil and so the voltage is always 127 or 220 and are connected in two stages and also by a phase and neutral. When connected several single-phase electric motors to the three-phase system care should be taken to distribute the voltage equally so that no load imbalance between the three phases.
Called MRT, the electric motor baldor 2016 single phase with return by land, it is a system in which the land is the source of the return conductor of the load current. Depending on the electrical system that exists and soil characteristics where the electric motor will be installed will:
Monofilar a system that is more economical and practical version of the MRT and you can only use the MRT if the output of the source substation is a grounded star. The system monofilar with electric motor insulation transformer single phase has disadvantages, and these disadvantages is the use of the transformer.
Finally, the MRT system of partial neutral version of the electric motor is mostly used in areas where the soil is of high resistivity.