Answer / e. segovia

In 3ph star connections we can prove by means of drawings
or maths methods that Line current = SQRT(3)*Phase
current, and in delta connections Line current = Phase
current, that is why we use star-delta connection for
heavy motor startings. This means we can lower the current
at starting and then after having overcome the system
inertia we swap to delta connection. worth mentioning that:
In delta, Line voltage = Phase voltage
In star, Line voltage = SQRT(3)*Phase voltage.

Answer / ald

Star connection--- Line current = phase current
Line voltage = phase voltage x 1.732

Delta connection --- Line voltage = Phase voltage
Line current = phase current x 1.732

Where the Dry type tranformers are used.

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