STATIONARY ENGINEER ELECTRIC
QUESTIONS AND VERIFIED ANSWERS
100% GUARANTEE PASS
uAn AC circuit consists only of a pure inductance and a power source. The relationship between the
voltage and the current in this circuit is that the - current lags the voltage
The power factor of a load is equal to the ____________ power divided by the ____________ power. -
True ; apparent
A 10-ohms and 20-ohms resistor are connected in parallel. The total line current drawn by this parallel
combination is 30 amps. Under these conditions, the line voltage will be ____________ volts. - 200
A 20-ohm resistor is connected in series with a parallel combination of two resistors, one of which is 10-
ohms, the other 40-ohms. If the voltage across the parallel combination is 40 volts, the voltage across
the 20-ohm series resistor is ________ volts. - 100
A certain 120-volts single-phase AC circuit has a power factor of 80 percent and a watt-meter reading of
1150 watts. The current drawn by the circuit is _________ amperes. - 12
If the voltage between lines of a 3-phase, 3-wire delta connected system is 2400 volts, then the phase
voltage is _____________ volts - 2400
A circuit consists of an inductive reactance of 15 ohms and a resistor of 20 ohms in series across a 100-
volts, 60 cycles AC supply. The current in this circuit is ____________ amperes. - 4
A 3 phase, 3 wire, 208 volt, 60 cycles AC service supplies a balanced load consisting of three 30 ohms
resistors connected wye. The line current under these conditions os MOST NEARLY ___________
amperes. - 6.9
,If the level of the electrolyte in a lead acid storage battery falls below the top of the plates because of
evaporations under normal operating conditions, it is BEST to add - Water
A 600 volt cartridge fuse must have knife blade contacts if its current rating exceeds _____________
amperes. - 60
When the magnitude of the short circuit currents in a feeder circuit must be limited, this is USUALLY
accomplished by means of - reactors
The cross sectional area in circular mils of a standard cable having 37 strands, each of which ha a
diameter of 90 nils, is MOST NEARLY - 300,000
A coil having an average diameter of 4 inches is to be made up from a 1,260 ft long length of wire. The
numbers of turns in this coil will be MOST NEARLY - 1,200
The device commonly known as a growler is FREQUENTLY used to - test DC armature windings for shorts
When a megger is applied alternately to the two leads of a direct current electrolytic capacitor, the
reading will - start at zero but increase gradually for one of the connections
The device used to convert direct current to alternating current is called - inverters
Of the following conditions, the one which is MOST likely to cause flashing or excessive arcing from brush
to brush in a motor is - Excessively high voltage on the line
The currents in the armature equalizer connections in a DC generator are - alternating currents
A generating station has one 1000 Kw and two 2000 Kw generators. To supply 2000 Kw MOST
economically, the operating conditions should be - one 2000 Kw generator at full load
,The terminal voltage of a DC shunt generator having an armature current of 100 amperes, an armature
resistance of 0.02 ohms, and a generated E.M.F of 222 volts is MOST NEARLY ______________ volts. -
220
The number of poles in the field of an alternator generating voltage at a frequency of 60 cycles per
second while rotating at 1200 rpm is - 6
If the field of a shunt motor opens while running, the motor will - run away
To reverse the direction of rotation of a cumulative compound motor, and not have it run as a differential
compound motor, reverse the connections to the ____________ field. - shunt field and to the series
A main contributing factor to motor stator failure usually is - dirt
The input of a motor is 40,000 watts and efficiency is 80 percent. The TOTAL energy loss is __________
watts. - 8,000
The full load current of a three-phase 5 hp motor operating at 200 volts, 60 cycles, and having an
efficiency of 80 percent and a power factor of 85 percent is MOST NEARLY ____________ amperes. -
14.4
Of the following motors, the one that has the best speed regulation is the motor. - shunt
The full load speed of a 60-cycle 208 volt, 3 phase induction motor having 6 poles and operating with a
slip of 10% is MOST NEARLY___________ r.p.m - 1080
Of the following, a MAJOR advantage of an AC synchronous motor is that it(s) - can be used for power
factor correction
If the field current of a synchronous motor is increased to a point which makes the synchronous motor
overexcited, the - motor will take a leading current
, When transformers are to be operated in parallel, it is NOT necessary that the transformer have the
same - KVA rating
A transformer rates at 200 KVA is FULLY loaded with a lagging power factor of 80% when it is supplying -
160 KW
If the current in the primary of a current transformer is 500 amperes and the transformer has a ratio of
100 to 5, an ammeter connected to the secondary will read MOST NEARLY___________ amperes. - 25
Assume that a switchboard ammeter which is connected to a current transformer is damaged and must
be removed without interrupting the service. Of the following, an ESSENTIAL precaution to be taken
before disconnecting the ammeter is to - short the secondary of the transformer
A DC relay is rated at 6 volts and 120 ohms. This relay can be operated from a 120 volt line by connecting
a ___________ ohm resistance in __________ with relay - 2280: series
Some relays are provided with dash-pots. The FUNCTION of these dash-pots is to provide - delayed time
action
An ammeter has a full scale deflection for a current of 0.01 amperes and an internal resistance of 20
ohms. In order to have the ammeter read full-scale for a current of 10 amperes and not damage its
movement, a shunt should be used having a value of__________ ohms. - 0.02
An air circuit breaker has contacts that flash. The MOST probable cause of this trouble is that the -
barriers are broken
The MAIN purpose of a shunt trip on a circuit breaker is to - permit the breaker to be opened electrically
from a remote location, regardless of load conditions at the breaker
The grid-controlled gas-type electronic tube MOST often used in motor control circuits is the - thyratron
Under normal atmospheric conditions, a pressure gauge that reads 24 inches of mercury is indicating an
absolute pressure of MOST NEARLY_____________ P.S.I. - 26.5
QUESTIONS AND VERIFIED ANSWERS
100% GUARANTEE PASS
uAn AC circuit consists only of a pure inductance and a power source. The relationship between the
voltage and the current in this circuit is that the - current lags the voltage
The power factor of a load is equal to the ____________ power divided by the ____________ power. -
True ; apparent
A 10-ohms and 20-ohms resistor are connected in parallel. The total line current drawn by this parallel
combination is 30 amps. Under these conditions, the line voltage will be ____________ volts. - 200
A 20-ohm resistor is connected in series with a parallel combination of two resistors, one of which is 10-
ohms, the other 40-ohms. If the voltage across the parallel combination is 40 volts, the voltage across
the 20-ohm series resistor is ________ volts. - 100
A certain 120-volts single-phase AC circuit has a power factor of 80 percent and a watt-meter reading of
1150 watts. The current drawn by the circuit is _________ amperes. - 12
If the voltage between lines of a 3-phase, 3-wire delta connected system is 2400 volts, then the phase
voltage is _____________ volts - 2400
A circuit consists of an inductive reactance of 15 ohms and a resistor of 20 ohms in series across a 100-
volts, 60 cycles AC supply. The current in this circuit is ____________ amperes. - 4
A 3 phase, 3 wire, 208 volt, 60 cycles AC service supplies a balanced load consisting of three 30 ohms
resistors connected wye. The line current under these conditions os MOST NEARLY ___________
amperes. - 6.9
,If the level of the electrolyte in a lead acid storage battery falls below the top of the plates because of
evaporations under normal operating conditions, it is BEST to add - Water
A 600 volt cartridge fuse must have knife blade contacts if its current rating exceeds _____________
amperes. - 60
When the magnitude of the short circuit currents in a feeder circuit must be limited, this is USUALLY
accomplished by means of - reactors
The cross sectional area in circular mils of a standard cable having 37 strands, each of which ha a
diameter of 90 nils, is MOST NEARLY - 300,000
A coil having an average diameter of 4 inches is to be made up from a 1,260 ft long length of wire. The
numbers of turns in this coil will be MOST NEARLY - 1,200
The device commonly known as a growler is FREQUENTLY used to - test DC armature windings for shorts
When a megger is applied alternately to the two leads of a direct current electrolytic capacitor, the
reading will - start at zero but increase gradually for one of the connections
The device used to convert direct current to alternating current is called - inverters
Of the following conditions, the one which is MOST likely to cause flashing or excessive arcing from brush
to brush in a motor is - Excessively high voltage on the line
The currents in the armature equalizer connections in a DC generator are - alternating currents
A generating station has one 1000 Kw and two 2000 Kw generators. To supply 2000 Kw MOST
economically, the operating conditions should be - one 2000 Kw generator at full load
,The terminal voltage of a DC shunt generator having an armature current of 100 amperes, an armature
resistance of 0.02 ohms, and a generated E.M.F of 222 volts is MOST NEARLY ______________ volts. -
220
The number of poles in the field of an alternator generating voltage at a frequency of 60 cycles per
second while rotating at 1200 rpm is - 6
If the field of a shunt motor opens while running, the motor will - run away
To reverse the direction of rotation of a cumulative compound motor, and not have it run as a differential
compound motor, reverse the connections to the ____________ field. - shunt field and to the series
A main contributing factor to motor stator failure usually is - dirt
The input of a motor is 40,000 watts and efficiency is 80 percent. The TOTAL energy loss is __________
watts. - 8,000
The full load current of a three-phase 5 hp motor operating at 200 volts, 60 cycles, and having an
efficiency of 80 percent and a power factor of 85 percent is MOST NEARLY ____________ amperes. -
14.4
Of the following motors, the one that has the best speed regulation is the motor. - shunt
The full load speed of a 60-cycle 208 volt, 3 phase induction motor having 6 poles and operating with a
slip of 10% is MOST NEARLY___________ r.p.m - 1080
Of the following, a MAJOR advantage of an AC synchronous motor is that it(s) - can be used for power
factor correction
If the field current of a synchronous motor is increased to a point which makes the synchronous motor
overexcited, the - motor will take a leading current
, When transformers are to be operated in parallel, it is NOT necessary that the transformer have the
same - KVA rating
A transformer rates at 200 KVA is FULLY loaded with a lagging power factor of 80% when it is supplying -
160 KW
If the current in the primary of a current transformer is 500 amperes and the transformer has a ratio of
100 to 5, an ammeter connected to the secondary will read MOST NEARLY___________ amperes. - 25
Assume that a switchboard ammeter which is connected to a current transformer is damaged and must
be removed without interrupting the service. Of the following, an ESSENTIAL precaution to be taken
before disconnecting the ammeter is to - short the secondary of the transformer
A DC relay is rated at 6 volts and 120 ohms. This relay can be operated from a 120 volt line by connecting
a ___________ ohm resistance in __________ with relay - 2280: series
Some relays are provided with dash-pots. The FUNCTION of these dash-pots is to provide - delayed time
action
An ammeter has a full scale deflection for a current of 0.01 amperes and an internal resistance of 20
ohms. In order to have the ammeter read full-scale for a current of 10 amperes and not damage its
movement, a shunt should be used having a value of__________ ohms. - 0.02
An air circuit breaker has contacts that flash. The MOST probable cause of this trouble is that the -
barriers are broken
The MAIN purpose of a shunt trip on a circuit breaker is to - permit the breaker to be opened electrically
from a remote location, regardless of load conditions at the breaker
The grid-controlled gas-type electronic tube MOST often used in motor control circuits is the - thyratron
Under normal atmospheric conditions, a pressure gauge that reads 24 inches of mercury is indicating an
absolute pressure of MOST NEARLY_____________ P.S.I. - 26.5
