What are the differences in the wiring configurations of star and delta systems, particularly in the context of DOL (Direct-On-Line) starters?

Question

Accepted Answer

Star and delta configurations differ in wiring, affecting motor starting and torque characteristics in DOL starters.

Star configuration connects each motor winding to a common point, reducing voltage and current during startup.
Delta configuration connects windings in a loop, providing full voltage and higher starting torque.
DOL starters typically use star configuration for high starting current reduction in large motors.
Example: A 400V motor in star will see 230V across each winding, while in delta, it sees the full 400V.
Star-delta starters switch from star to delta after a set time to reduce initial inrush current.

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