Preca Solutions Interview Questions and Answers

A DOL starter is a direct-on-line motor starter used to start and stop motors without any speed control.

• DOL stands for Direct-On-Line.

• It is the simplest and most common type of motor starter.

• It directly connects the motor to the power supply, providing full voltage at start.

• It consists of a contactor, overload relay, and start and stop buttons.

• The contactor closes to supply power to the motor, while the overload relay ...read more

Relay is an electrically operated switch that controls the flow of current in a circuit. MCB is a miniature circuit breaker that protects electrical circuits from overcurrents. Contactor is an electrically controlled switch used for controlling power circuits.

• Relay is used to control high power circuits with low power signals.

• MCB automatically trips and disconnects the circuit in case of overcurrents.

• Contactor is commo...read more