True/False
Indicate whether the
statement is true or false.
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1.
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In a wye connection, the line current and phase current are not the same.
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2.
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Dual voltage motors not intended for wye-delta connection will have certain
terminals tied internally.
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3.
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Dual voltage motors designed for wye-delta starting will supply all 12 T leads
at the terminal connection box.
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4.
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Closed transition starting does not disconnect the motor from the power
line.
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5.
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Open transition starting means that the motor is connected to the power line
during the transition from wye to delta.
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Completion
Complete each
statement.
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6.
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Wye-delta starting is sometimes called ____________________ starting.
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7.
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If the stator windings of a motor are connected in delta during the starting
period, the starting current will be ____________________ times the value if the windings were
connected in wye.
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8.
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If the stator windings are connected in ____________________, the voltage across
each phase will be 480 volts because line voltage and phase voltage are the same in a(n)
____________________ connection.
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9.
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Wye-delta starting is often used with large horsepower motors to reduce in-rush
current during the starting period and reduce starting ____________________.
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10.
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Motors that are intended to operate on two voltages such as 240 or 480 volts
contain two separate ____________________ of each phase.
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Short Answer
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Figure 26-1 
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11.
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What does the accompanying figure show?
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12.
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What are the two requirements that must be met before wye-delta starting can be
used?
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13.
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How is wye-delta starting accomplished?
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Figure 26-9 
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14.
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What does the accompanying diagram show?
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15.
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What is the most critical part of connecting a wye-delta starter?
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