sentences:  Four main component systems form the basis of a modern induction heater
  
  Induction heating is a non contact method of heating a conductive body by utilising a strong magnetic field.Supply (mains) frequency 50 Hz or 60 Hz induction heaters incorporate a coil directly fed from the electricity supply, typically for lower power industrial applications where lower surface temperatures are required.Some specialist induction heaters operate at 400 Hz, the Aerospace power frequency.