What type of starting is best suited for applications requiring low starting torque and minimal line current?

The type of starting that is best suited for applications requiring low starting torque and minimal line current is Wye Delta Starting. This method is particularly beneficial for three-phase induction motors.

In Wye Delta Starting, the motor begins its operation in a wye configuration, which reduces the voltage across the motor windings, thus decreasing the starting current and resulting in a lower starting torque. Once the motor reaches a certain speed, typically around 70-80% of its rated speed, the configuration switches to delta. In delta configuration, the motor runs at full voltage, allowing it to reach its full operational capacity.

This starting method is effective in applications where lower starting torque is required, such as with fans or pumps, where a sudden high torque may not be necessary and could cause damage or dangerous conditions. Additionally, by limiting the line current during start-up, Wye Delta Starting helps to prevent voltage drops in the power supply, which can affect other equipment on the same line.

In contrast, other starting methods such as Full Voltage Starting, Soft Starting, and Direct On-Line Starting typically result in higher starting torques and higher inrush currents, which can be detrimental in applications where load characteristics require careful management of both starting torque and line current.