LADWP ELECTRIC STATION OPERATOR(
CIRCUIT BREAKERS, DISCONNECTS,
TRANSFORMERS) EXAM 2026
Silicon - ANSWER-__________ steel, which has a high permeability rating, is
used as a material for manufacturing transformer cores.
98 - ANSWER-Well-designed transformers are about _____% efficient.
excitation - ANSWER-Since they have no moving parts, the only losses are
those caused by field __________ when a transformer is energized, and
resistance of the core material.
Eddy - ANSWER-Circulating currents, called __________ currents, cause
unwanted heating of the transformer and a loss of energy.
silicon - ANSWER-By laminating it, using thin sheet of __________ steel or
other ferrous alloys sprayed with an insulating material, eddy currents are
greatly reduced in transformers cores.
Hysteresis - ANSWER-The heat and accompanying loss of energy caused by
friction of the molecules is called __________.
iron - ANSWER-The losses of electrical energy that appear as heat and which
are cause by hysteresis and eddy currents in the magnetic core are known as
__________ losses.
, copper - ANSWER-The losses due to the resistance of the windings care called
_________ losses or I2R losses.
insulating - ANSWER-The heat caused by iron and copper losses shortens the
service life of __________ materials used in transformer windings. This may
cause premature transformer failure.
current - ANSWER-High temperature limits the __________ carrying capacity
of transformers.
cooling - ANSWER-_________ not only helps extend the life of transformers
but also increases its current carrying capacity.
hot spots - ANSWER-Localized areas of greater heat are called __________.
transformers - ANSWER-Small and medium sized __________ are self-cooled;
that is; cooling takes place by direct radiation from the tank to the surrounding
air.
30 - ANSWER-Transformer oil in good condition must be able to withstand
_____kV applied across two flat electrodes submerged in a staple of the oil
without arcing.
Turns - ANSWER-__________-ratio is the number of turns of wire in the
primary winding compared to the number of turns in the secondary winding.
transformer - ANSWER-An ideal __________ is one in which all the lines of
force produced by the primary winding inductively link every turn of the
secondary winding.
CIRCUIT BREAKERS, DISCONNECTS,
TRANSFORMERS) EXAM 2026
Silicon - ANSWER-__________ steel, which has a high permeability rating, is
used as a material for manufacturing transformer cores.
98 - ANSWER-Well-designed transformers are about _____% efficient.
excitation - ANSWER-Since they have no moving parts, the only losses are
those caused by field __________ when a transformer is energized, and
resistance of the core material.
Eddy - ANSWER-Circulating currents, called __________ currents, cause
unwanted heating of the transformer and a loss of energy.
silicon - ANSWER-By laminating it, using thin sheet of __________ steel or
other ferrous alloys sprayed with an insulating material, eddy currents are
greatly reduced in transformers cores.
Hysteresis - ANSWER-The heat and accompanying loss of energy caused by
friction of the molecules is called __________.
iron - ANSWER-The losses of electrical energy that appear as heat and which
are cause by hysteresis and eddy currents in the magnetic core are known as
__________ losses.
, copper - ANSWER-The losses due to the resistance of the windings care called
_________ losses or I2R losses.
insulating - ANSWER-The heat caused by iron and copper losses shortens the
service life of __________ materials used in transformer windings. This may
cause premature transformer failure.
current - ANSWER-High temperature limits the __________ carrying capacity
of transformers.
cooling - ANSWER-_________ not only helps extend the life of transformers
but also increases its current carrying capacity.
hot spots - ANSWER-Localized areas of greater heat are called __________.
transformers - ANSWER-Small and medium sized __________ are self-cooled;
that is; cooling takes place by direct radiation from the tank to the surrounding
air.
30 - ANSWER-Transformer oil in good condition must be able to withstand
_____kV applied across two flat electrodes submerged in a staple of the oil
without arcing.
Turns - ANSWER-__________-ratio is the number of turns of wire in the
primary winding compared to the number of turns in the secondary winding.
transformer - ANSWER-An ideal __________ is one in which all the lines of
force produced by the primary winding inductively link every turn of the
secondary winding.
