Complementary to our liquid resistance starter offerings we also provide stepped resistor starters. These starters contain fixed resistors manufactured from cast iron that are successively short circuited from the rotor circuit by power contactors. The resistors are usually cooled by natural convection but can also be oil immersed.
Stepped resistor starters are especially suitable for conveyor drive applications where multiple motors are driving one belt due to the exact resistance control. Also the oil immersed 3PA oil cooled starters are capable of operating in lowest temperatures without additional heating measures.