The consumption of power in the industrial field almost reaches approximately 40%
of the total generated power. One kind of useless consumption of power is the losses in the
electrical motors starting. The impact of the losing power might be ignore
d in the
continuous and short time working systems. However, in case of periodic starting up, the
losing ratio will be exaggerated. Also, the controlling of starting up process will be
considerable and can keep the losses at lowest levels. In this paper, the effect of using the
Semi-conductors controlling system in DC motors on power losses was studied and
compared with control system using resistors starting in periodic short time systems. The
obtained results show that there is a relationship between the power saving in KWh per
year as a function of the rated motor power and the number of starting up per Hour. Due to
conveying from conventional controlling system to modern control system uses semiconductor
rectifier.
