TRANSFORMERS LEVEL II LESSON 2
SCRIPT COMPLETE ANSWERS GRADED
A+
◉ When exposed to very high currents from short circuits,
transformer coils have a tendency to move, or telescope, in
opposite directions. To minimize the probability of telescoping,
coils are designed so that the electrical centers of the two coils are
in an identical position. Additionally, both windings are rigidly
clamped in place to prevent movement.
Answer: True
◉ A shell-type transformer has an equal number of legs and
windings.
Answer: False
◉ Match the different types of transformers to the corresponding
items in the illustration.
Answer: Core Type
Shell Type
Torodial
◉ In a dry-type transformer, air is used to cool the coils.
Answer: True
, ◉ Liquid-immersed transformers are typically immersed in ? .
Answer: Oil
◉ Askarels are often used instead of mineral oil as a cooling fluid
in newer transformers.
Answer: False
◉ The temperature rise in a transformer is the difference between
the hot-spot maximum core temperature and the average
operating temperature.
Answer: False
◉ The allowable temperature rise for a Class 150 (B) transformer
is ? .
Answer: 80° C
◉ A(n) ? is a pipe, four inches in diameter or greater, that extends
a few feet above the cover of a transformer and is curved toward
the ground at the outlet end of the pipe.
Answer: Explosion Vent
◉ A(n) ? is a transition device between underground cable and
lines.
Answer: Pothead
SCRIPT COMPLETE ANSWERS GRADED
A+
◉ When exposed to very high currents from short circuits,
transformer coils have a tendency to move, or telescope, in
opposite directions. To minimize the probability of telescoping,
coils are designed so that the electrical centers of the two coils are
in an identical position. Additionally, both windings are rigidly
clamped in place to prevent movement.
Answer: True
◉ A shell-type transformer has an equal number of legs and
windings.
Answer: False
◉ Match the different types of transformers to the corresponding
items in the illustration.
Answer: Core Type
Shell Type
Torodial
◉ In a dry-type transformer, air is used to cool the coils.
Answer: True
, ◉ Liquid-immersed transformers are typically immersed in ? .
Answer: Oil
◉ Askarels are often used instead of mineral oil as a cooling fluid
in newer transformers.
Answer: False
◉ The temperature rise in a transformer is the difference between
the hot-spot maximum core temperature and the average
operating temperature.
Answer: False
◉ The allowable temperature rise for a Class 150 (B) transformer
is ? .
Answer: 80° C
◉ A(n) ? is a pipe, four inches in diameter or greater, that extends
a few feet above the cover of a transformer and is curved toward
the ground at the outlet end of the pipe.
Answer: Explosion Vent
◉ A(n) ? is a transition device between underground cable and
lines.
Answer: Pothead
