277 Copyright Goodheart-Willcox Co., Inc. Name __________________________________________ Date _______________________ Class ______________________ The purpose of this lab is to acknowledge the operation of a three-phase motor under normal and no start conditions and to check state of windings with an ohmmeter. Lab 13.3 Three-Phase Motor Analysis Delta Configuration Wye Configuration T3 T2 L1 L2 L3 L1 L2 L3 T1 T3 T2 T1 Goodheart-Willcox Publisher Figure 13.3-1. Lab Introduction This lab will require an operational three-phase motor and three-phase power. Power should be delivered to the motor through a three-pole contactor of directly from a three-pole single-throw disconnect or switch. Voltage imbal- ance will be calculated, and phase currents will be measured. In addition, winding resistance will be measured. Note the motor is not connected to a mechanical load. Equipment • 1/4 hp three-phase motor single or dual voltage (wired for low voltage) • Safety glasses • Three-pole disconnect, three-pole single-throw switch (rated for motor) or three-pole contactor with 120 V coil. • Multimeter with inductive clamp