What are the control and power wiring configurations for star-delta and direct-on-line (DOL) starters?

Question

Accepted Answer

Star-delta and DOL starters have distinct wiring configurations for controlling motor operations efficiently.

DOL Starter: Directly connects the motor to the power supply, providing full voltage.
Star-Delta Starter: Initially connects the motor in star configuration to reduce voltage, then switches to delta for full power.
DOL is simpler and used for smaller motors (up to 5 HP).
Star-Delta is preferred for larger motors (above 5 HP) to reduce starting current.
Control wiring for DOL includes a contactor and overload relay.
Star-Delta control wiring involves two contactors (one for star, one for delta) and a timer.

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