STATIONARY ENGINEER EVALUATION EXAM QUESTIONS
AND SOLUTIONS RATED A+
✔✔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
✔✔The PRIMARY function of a hydrometer is to measure the rate of - ✔✔relative
humidity
✔✔A venturi meter is used to measure the rate of - ✔✔fluid flow
✔✔The PRINCIPLE thickening agent used in lubricating greases is - ✔✔metallic soap
✔✔The specific gravity of liquid is USUALLY determined by means of a -
✔✔hydrometer
✔✔The pull required on the fall line (negating friction) to hoist a 120 pounds weight,
using a four-part block and tackle, is ___________ lbs. - ✔✔30
✔✔Of the following terms, the one which does NOT describe a way of finishing the ends
of a rope is the - ✔✔bight
✔✔When hoisting a load by means of sling, the stress in each leg of the sling will -
✔✔increase as the angle between the horizontal and the sling leg decreases
, ✔✔The MAXIMUM pressure in an upright cylinder 6 feet in diameter, 8 feet high, and
open at the top, when filled tot he brim with water, is MOSTLY NEARLY
______________ lbs/sq.ft. - ✔✔500
✔✔The MAXIMUM height to which water can be lifted by means of suction alone, at sea
level, is APPROXIMATELY _____________ feet. - ✔✔34
✔✔The TOTAL number of 4 inch diameter pipe that is required to equal the water flow
capacity of an 8 inch diameter pipe (negating friction) is - ✔✔4
✔✔The number of threads, per inch, on the standard machine screw MOST suitable for
general use is - ✔✔32
✔✔The friction losses which occur when water flows through a pipe vary MOST
NEARLY _____________ with the ____________. - ✔✔directly; velocity squared
✔✔Small by-pass lines are sometimes furnished around large gate valves MAINLY to -
✔✔balance the pressure on the gate when the valve is being opened
✔✔The sudden surge caused by an abrupt change in the speed of the pumps in a
closed liquid piping system is USUALLY called - ✔✔water hammer
✔✔The valve that permits water to flow one direction only is the ____________ valve -
✔✔check
✔✔Most flanged butterfly valves can be brought from a fully closed position to a fully
opened position in _____________ turn(s). - ✔✔a quarter
✔✔The efficiency of two centrifugal pumps operating in parallel is ___________ of one
of the pumps operating alone. - ✔✔practically the same as that
✔✔Assume that a spur gear having 20 teeth revolves at 80 r.p.m and drives another
super gear having 40 teeth. The speed at which the gear having 40 teeth revolves is
_____________ r.p.m. - ✔✔40
✔✔A centrifugal pump has a plain flat-joint seal between the impeller and the casting. If
the clearance of the seal become enlarged due to wear, thereby reducing the pump's
efficiency, it would be GOOD practice to - ✔✔renew the impeller
✔✔The one of the following statement which CORRECTLY describes a speed
characteristic for a centrifugal pump under normal operating conditions is: - ✔✔Total
head varies directly with the square of the speed
AND SOLUTIONS RATED A+
✔✔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
✔✔The PRIMARY function of a hydrometer is to measure the rate of - ✔✔relative
humidity
✔✔A venturi meter is used to measure the rate of - ✔✔fluid flow
✔✔The PRINCIPLE thickening agent used in lubricating greases is - ✔✔metallic soap
✔✔The specific gravity of liquid is USUALLY determined by means of a -
✔✔hydrometer
✔✔The pull required on the fall line (negating friction) to hoist a 120 pounds weight,
using a four-part block and tackle, is ___________ lbs. - ✔✔30
✔✔Of the following terms, the one which does NOT describe a way of finishing the ends
of a rope is the - ✔✔bight
✔✔When hoisting a load by means of sling, the stress in each leg of the sling will -
✔✔increase as the angle between the horizontal and the sling leg decreases
, ✔✔The MAXIMUM pressure in an upright cylinder 6 feet in diameter, 8 feet high, and
open at the top, when filled tot he brim with water, is MOSTLY NEARLY
______________ lbs/sq.ft. - ✔✔500
✔✔The MAXIMUM height to which water can be lifted by means of suction alone, at sea
level, is APPROXIMATELY _____________ feet. - ✔✔34
✔✔The TOTAL number of 4 inch diameter pipe that is required to equal the water flow
capacity of an 8 inch diameter pipe (negating friction) is - ✔✔4
✔✔The number of threads, per inch, on the standard machine screw MOST suitable for
general use is - ✔✔32
✔✔The friction losses which occur when water flows through a pipe vary MOST
NEARLY _____________ with the ____________. - ✔✔directly; velocity squared
✔✔Small by-pass lines are sometimes furnished around large gate valves MAINLY to -
✔✔balance the pressure on the gate when the valve is being opened
✔✔The sudden surge caused by an abrupt change in the speed of the pumps in a
closed liquid piping system is USUALLY called - ✔✔water hammer
✔✔The valve that permits water to flow one direction only is the ____________ valve -
✔✔check
✔✔Most flanged butterfly valves can be brought from a fully closed position to a fully
opened position in _____________ turn(s). - ✔✔a quarter
✔✔The efficiency of two centrifugal pumps operating in parallel is ___________ of one
of the pumps operating alone. - ✔✔practically the same as that
✔✔Assume that a spur gear having 20 teeth revolves at 80 r.p.m and drives another
super gear having 40 teeth. The speed at which the gear having 40 teeth revolves is
_____________ r.p.m. - ✔✔40
✔✔A centrifugal pump has a plain flat-joint seal between the impeller and the casting. If
the clearance of the seal become enlarged due to wear, thereby reducing the pump's
efficiency, it would be GOOD practice to - ✔✔renew the impeller
✔✔The one of the following statement which CORRECTLY describes a speed
characteristic for a centrifugal pump under normal operating conditions is: - ✔✔Total
head varies directly with the square of the speed
