Intro To Transformers Flashcards
The only way to produce a voltage in a conductor is to move a conductor through a magnetic field past a conductor.
a) True
b) False
b) False; a voltage is produced by relative motion between a conductor and a magnetic field. Either moving a conductor though a magnetic field or moving a magnetic field past a conductor produces a voltage.
If the turns in the secondary coil of a transformer are decreased, (more, less) voltage is induced in the secondary of the transformer.
If the turns in the secondary coil of a transformer are decreased, LESS voltage is induced in the secondary of the transformer.
A self- or mutually-induced voltage only occurs when the current is not changing.
a) True
b) False
b) False
self- or mutually-induced voltage only occurs when the current IS changing.
A transformer is an alternating current device that generates electrical energy.
a) True
b) False
b) False
A transformer is an alternating current device that TRANSFERS electrical energy.
The basic mutual induction transformer has at least two coils or windings of wire wound on a common core.
a) True
b) False
a) True
A step up transformer is used where the output voltage is to be (higher, lower) than the input voltage
Higher
A step down transformer is used where the output voltage is to be (higher, lower) than the input voltage
Lower
The efficiency of a transformer is (very high, very low) over a wide range of loads.
Very high
The input winding connected to the energy source is the (primary, secondary) winding.
Primary
The output winding connected to the energy source is the (primary, secondary) winding.
Secondary
The terminals of the high-voltage winding are marked with the letter (H, X).
H
The terminals of the low-voltage winding are marked with the letter (H, X).
X
What test is performed on a transformer to determine its percent impedance?
A short circuit test is performed to determine a transformers percent impedance.
Why should you not apply more than 110% of the rated voltage to the primary winding of a transformer?
The primary current increases to unacceptable levels and the transformer burns out
When looking at a transformer from the low-voltage side, the standard H1 terminal position is located at:
a) the upper right hand corner
b) the lower right hand corner
c) the upper left hand corner
d) the lower right hand corner
c) the upper left hand corner
