Question 258Electricity/Electronics - Assistant Engineer70% to pass
As shown in the two-speed single winding three phase motor connection diagrams illustrated in figure "B", what is the connection scheme associated with low-speed operation? Illustration EL-0118
AI Explanation
The correct answer is B) series delta.
In the series delta connection scheme, the windings of the three-phase motor are connected in a delta configuration, but the windings are connected in series rather than in parallel. This results in a lower speed operation of the motor compared to the parallel delta connection.
The other options are incorrect because:
A) Parallel delta would result in higher speed operation.
C) Parallel wye would also result in higher speed operation.
D) Series wye is a different configuration that would not achieve the low-speed operation shown in the diagram.
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