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Many transistor controlled variable frequency drives now employ a special type of transistor called a(n) ______________________________.

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IGBT,Insulated Gate Bipolar Transistor,IGBT (Insulated Gate Bipolar Transistor)

How do most variable frequency drives operate?

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Most variable frequency drives...

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Variable frequency drives intended to control the speed of  motors up to 500 HP generally use ____________________.

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Drives using Insulated Gate Bipolar Transistors (IGBTs) generally used ____________________ to rectify the AC voltage into DC.

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diodes

Changing frequency causes a corresponding change in the inductive reactance of the windings.

A) True
B) False

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What are two basic methods of achieving variable frequency?

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Two basic methods of...

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The output frequency of the alternator is determined by the speed of the ____________________.

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Alternators are often used to control the speed of several induction motors that require different changes in speed.

A) True
B) False

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False

The Insulated Gate Bipolar Transistor (IGBT) is a current controlled device, not a voltage controlled device.

A) True
B) False

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What are thyristors?

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Thyristors are solid-state dev...

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How can the speed on a three phase induction motor be controlled?

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The speed of a three phase induction mot...

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What is an advantage of using Insulated Gate Bipolar Transistors (IGBTs) for drives?

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A great advantage of drives us...

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Ramping permits the motor to bring the load up to speed slowly as opposed to simply connecting the motor directly to the line.

A) True
B) False

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When bipolar junction transistors are employed as switches, they are generally driven into ____________________ by supplying them with an excessive amount of base-emitter current .

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Inverter rated motors are specifically designed to be operated by variable frequency drives.

A) True
B) False

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Showing 1 - 15 of 15

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