Number of resistor steps of a starter that are bridged by switches or contactors during the start. The number of starting steps depends on the desired ratio of peak starting current I₂ to switching current I₁ at which the next step is switched. The stepping factor (Greek Lambda) λ = I₂/I₁ indicates by how much the starting resistance exceeds the previous step, and by how much it is smaller than the next step. The required number of steps is calculated as follows

, whereby Ra is the complete starting resistance and Ri the ohmic resistance of the rotor and possibly the lines between rotor and resistor. If a slip resistance is planned, this shall also be included in the Ri. λ and m are interdependent. A small λ requires a high number of steps and vice versa.