True/False
Indicate whether the
statement is true or false.
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1.
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Across-the-line starting is the simplest of all starting methods.
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2.
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Across-the-line starting is only used for alternating current.
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3.
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The type of bars used to construct the rotor has a great effect on the operating
characteristics of the motor.
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4.
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Direct current motors depend on inductive reactance to limit current
flow.
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5.
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Contactors intended to connect direct current motors to the line often have arc
suppression and magnetic blowout coils.
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Completion
Complete each
statement.
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6.
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The type of rotor is identified by a code letter on the ____________________ of
a motor.
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7.
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In-rush current is referred to a(n) ____________________ current.
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8.
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In a DC contactor with two coils, the ____________________ coil is intended for
momentary duty and not continuous operation.
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9.
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Direct current motors require only one ____________________ contact to connect
or disconnect them to the power line and one overload sensing device.
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10.
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In a grounded system, the current sensing device must be in the
____________________ conductor.
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Short Answer
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11.
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How is across-the-line starting accomplished?
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12.
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In direct current motors, by what is the initial in-rush current limited?
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13.
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Why is it that small DC motors can be started across-the-line?
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14.
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Some DC contactors contain two separate coils. Describe the two coils.
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15.
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What do direct current starters and contactors that do not utilize arc
suppressors or magnetic blowout coils use to break the circuit?
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