Oil Cooled Transformers for Motor Starting

TMC produces oil cooled motor starting auto-transformers to suit all motor capacities.


Motor Starting Transformer Characteristics

Motor starting transformers are auto transformers with tappings in the range of 50% to 70% of rated voltage (customer specified). The motor to be started is switched through the auto transformer in such a way as to start the motor at a lower voltage to minimise starting load and the associated supply voltage drop. This method is often referred to as the “Korndorfer Starter” method.

Information Required with Enquiry:

  • Voltages (at no-load)
  • Voltage tapping range.
  • Number of phases (normally 3)
  • Operating frequency
  • Motor rating
  • Motor locked-rotor current
  • Motor start duration (seconds)
  • Number of starts per hour
  • Ambient conditions
  • Design standard
  • Enclosure protection rating
  • Temperature sensing equipment
  • Current sensing equipment (CT’s).