Product Manual

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Wye-Delta Starting
• Wye-Delta Starting can be used with motors where all six leads of
the stator winding are available (on some motors only three leads
are accessible).
• By first closing contacts A and B, the windings are connected in
a wye configuration which presents 57% of rated voltage to the
motor.
• Full voltage is then applied by reconnecting the motor in a delta
configuration by closing contacts C and opening those at A.
• The starting current and torque are 33% of their full voltage ratings,
limiting applications to loads requiring very low starting torque.
Motor windings
Figure 4.5
Wye-Delta Starter