 Normally, the electrical configuration of windings is varied from a delta connection (Δ) to a double star connection (YY) configuration in order to change the speed of the motor for constant torque applications, such as the hoists in cranes.Star connections (Y) varied to double star connections (YY) are used for quadratic torque applications, such as pumps.Dahlander motors have advantages compared to other speed control systems like variable frequency drives, as there is less power loss.