Typically, which type of starter reduces voltage and current values to approximately 80% of normal readings?

Primary resistor starters are designed to limit the starting voltage and current of an electric motor by inserting resistors in series with the motor windings during startup. This method effectively reduces the applied voltage to the motor, typically to about 80% of the normal line voltage. As a result, the motor experiences a softer start, which helps to reduce mechanical stress and electrical demands during startup. Once the motor reaches a certain speed, the resistors can be switched out of the circuit, allowing the motor to run at full voltage.

Other types of starters often utilize different methods to manage starting conditions. Soft starters primarily use solid-state electronics to gradually ramp up the voltage, avoiding the drastic voltage drop associated with series resistors. Closed transition starters switch between different voltage supply methods but do not inherently reduce voltage like a primary resistor starter does. Autotransformer starters employ a transformer to step down voltage initially but do not achieve the same voltage reduction as a primary resistor starter in terms of percentage values.