Three phase induction is the most common motor and is widely used in various
industrial equipment because of all the advantages. To get the best performance,
the quality of powersupply of induction motors needs to be maintained. One of the
problems that arise in power quality is under voltage or over voltage. In this study
the calculation and analysis of efficiency using the segregated loss method of 3
phase induction motors connected to stars and delta on the under voltage and over
voltage conditions of the rating voltage, and at the rating voltage, the motor used
is a 3 Phase 1 HP 4 pole induction motor with voltage rating of 380 volts. The
method used is the segregated loss method, this method is a method to get the value
of the efficiency of the induction motor by finding and separating the value of loss
and loss, the method used refers to IEEE 112. Simulation using PSIM software as
a hypothesis and comparison, variables taken are speed, current, inter-phase
voltage and input power. Based on the results of calculations from all experiments
show that the induction motor will produce better efficiency at loads approaching
its capacity, and under voltage and over voltage conditions affect the efficiency
value with a small difference in each change in voltage conditions. Efficiency values
in all star motor voltage conditions range between 44% - 52% and in delta
connection motor ranges between 39% - 42%. Simulations carried out using PSIM
software produce higher efficiency than the test results with a range of values of
67% -78%, where the value is calculated from the simulation results and ignoring
core losses.