3A2

Three sub categories of butterfly valves are A. Wing-through B. Large C. Small D. Lined E. High performance

A, D, E Wing-through, lined and high performance

Select advantages of electrical valve operators 1. Can be set up for operation from several different locations-remotely operated 2. Remote indicating devices can be installed to show position of valve at any location 3. Valve operating speeds to close valves 2 seconds for some units to 4 minutes can be reached 4. Valves can be operated without personnel having to climb layers or enter dangerous locations A. 1,2,3,4 B. 2,3,4 C. 3,4 D.4 E.1,4

A. 1,2,3,4

AC generators have two different types of stators, they are? 1. Salient Pole 2. Armature Pole 3. Winding Pole 4. Cylindrical Pole 5. Casing Pole A. 1,4 B. 1,5 C. 2,3 D. 4,5 E. 3,4

A. 1,4

Alternators generally run at: A. 2 pole 3600rpm and 4 pole 1800 rpm B. 4 pole 1800rpm & 2 pole 3600rpm C. 3 pole and 6 pole D. 1600rpm or 1800rpm E. 4 pole 1700rpm & 2 pole 1800rpm

A. 2 pole 3600 and 4 pole 1800rpm

Induction motors w wound rotors are classed as: A. Adjustable speed motors B. purpose speed motors C. Adjustable frequency motors D. Dulong speed motors E. Constant torque motors

A. Adjustable speed motors

The yoke is made of? A. Cast iron or steel B. Aluminum or bronze C. Brass D. Cast iron or brass E. Aluminum or bronze

A. Cast iron or steel

When you are synchronizing an electrical generator and the synchronizing lamps are dark, you? A. Should have higher voltage ratings than the line system B. Have lower voltage C. Two or more lamps connected in parallel D. Should have coloured glass E. Higher current ratings than in line system

A. Have higher voltage ratings than the line system

Increase in conductor length will? A. Increase resistance B. Decrease resistance C. Cause no immediate effect on the electrical current D. Increase voltage proportionally with current E. Decrease current flow

A. Increase resistance

In a shunt motor, if the field becomes disconnected during operation the motor will? A. Over speed B. Under speed C. Slow down D. Stop E. Not change

A. Over speed

Excitation of the shunt field is controlled by? A. Regulating rheostat B. Mechanical governor C. Converter D. Long shunt E. Short shunt

A. Regulating rheostat

Large starting torque the DC motor to use would be A. Series B. Long shunt C. Short shunt D. Compound E. Cumulative compound

A. Series

The most common type of rotor used in induction motors is: A. Squirrel cage B. wound cage C. Slip D. Forged cage E. Inclosed

A. Squirrel cage

The yoke in a DC machine is usually made of? A. Steel B. Copper C. Aluminum D. Insulation E. Semi conductive material

A. Steel

Self inductance is said to be: A. Opposition additional to that provided by the resistance of the coil B. Opposition of emf produced by flux lines C. Capacitance in a AC circuit D. Inductance in a DC circuit E. A non relative factor in calculating impedance

A. The opposition additional to that provided by the resistance of the coil

Best method of synchronizing an alternator to a system is? A. The synchroscope B. Dark lamp C. One dark and two light lamps D. Phase indicator E. All dark rotating brushes

A. The synchroscope

The magnetomotive force in a magnetic circuit has it's equivalent in electric circuit which is the? A. Voltage B. Current C. Magnetic flux D. Inductance E. Reluctance

A. Voltage

If the current and voltage are in phase, the power factor is: A. Doubled B. 1 C. .75 D. Calculated at a constant value E. .5

B. 1

Three types of automatic starters for DC motors, they include 1.line 2. Current limit 3. Time limit 4. Field 5. Counter emf A. 1,3,5 B. 2,3,5 C. 1,3,4 D. 1,4,5 E. 2,4,5

B. 2,3,5

Common voltages used by three phase motors are: A. 220-420v B. 600-460v C. 220-120v D. 420-600v E. 420-220v

B. 600-460v

VFD's are also called: A. Partial and intake control devices B. AC drives and inverters C. DC drives and converters D. Frequency overdrive control systems E. Partial power outtake inverters

B. AC drives and inverters

Salient pole alternators? A. Are used for high speed B. Are used on alternators not exceeding 1800rpm C. Require little maintenance D. Are used on only single phase alternators E. Are used for only three phase applications

B. Are used on alternators not exceeding 1800rpm

The assembled armature core has? A. Field windings B. Axial slots around it's periphery C. Contact w the brushes D. Hand drawn copper bars E. No induced EMF

B. Axial slots around it's periphery

Simple electrical circuit consists of? A. Source, load, resistance B. Conductor, load, source C. Current, resistance, conductor D. Voltage, current, conductor E. Voltage, inductance, conductance

B. Conductor, load, source

In a magnetic circuit, the magnetic flux is the equivalent of electric ? A. Voltage B. Current C. Flux D. Reluctance E. Inductance

B. Current

In a capacitive circuit the current flowing is: A. Inversely proportional to the capacitance B. Directly proportional to the capacitance C. Always DC D. Directly proportional to electric potential E. AC or DC

B. Directly proportional to the capacitance

A DC generator is a DC machine driven by an? A. DC source B. Prime mover C. Qualified personnel D. AC source E. Electromotive force

B. Prime mover

As the flux of a shunt motor remains constant it's torque is? A. Inversely proportional to armature current B. Proportional to armature current C. Increased D. Decreased E. Unchanged

B. Proportional to armature current

According to ohms law: A. Raise I, R will increase B. Raise E, I will increase C. Raise R, I will increase D. Lower R, I will decrease E. Raise E, I will decrease

B. Raise E, I will increase

Behaviour of a separately excited generator with regard to the load characteristic is that load increases, it's delivery voltage: A. Steeply rises B. Remains constant C. Slightly falls D. Fluctuates E. Slightly above normal

B. Remains constant

Armature reaction causes the neutral plane to: A. Induce reactance B. Shift so that the brushes are now shorting coils C. Remain constant and supply steady voltage D. Remain constant and supply a steady flow of current E. Cause a resistance necessary to maintain voltage drop

B. Shifting so thAt the brushes are now shorting coils

Where approx constant speed the DC motor to use would be? A. Series B. Shunt C. Compound D. Separately excited E. Self excited

B. Shunt

Three phase machines are generally: A. More expensive and require more maintenance than single phase machines B. Smaller, lighter in weight and more efficient than single phase machines of the same rated capacity C. Long lasting but are not cost efficient for maintenance purposes D. Only used with AC power generation E. Only adaptable to generators that are of shunt or series type

B. Smaller, lighter in weight and more efficient than single phase machines of the same rated capacity

In regards to frequency the number of times from positive maximum, negative maximum and back to zero in one second is given the unit: A. Ohms B. hertz C. Volts D. DC E. Amps

B. hertz

The gas that was chosen universally in the place of air for generator cooling is: A. Nitrogen B. hydrogen C. Oxygen D. Helium E. Methane

B. hydrogen

When current reaches it's maximum value later than voltage it is said to be a lagging current, this happens in a circuit having ? A. Capacitance load B. inductive load C. In phase load D. Insulating load E. Reactive load

B. inductive load

Synchronous motors run at a leading power factor and are: A. Self starting B. not self starting C. Inexpensive D. Inefficient E. The most used motor in industry

B. not self starting

Wound rotor motors are used for: A. High velocity applications B. speed control C. Process control D. Delta connected machines E. Rotating field applications

B. speed control

Ohms law states: A. The quantity of matter is proportional to the electron flow B. The current is equal to the resistance multiplied by the emf C. Quantity of current flow is inversely proportional to the resistance for a given voltage D. Increase in wattage is decrease in amperage E. The direction of electrons at any given time equals the resistance multiplied by the length of the conductor

C. Quantity of current flow is inversely proportional to the resistance for a given voltage

Rotor is forged of: A copper B. soft steel laminations C. Solid steel up to 50-60 tonnes D. Micanite insulation E. Brass

C. Solid steel up to 50-60 tonnes

The phase relationship of incoming machine and the system requires the use of a synchronizing device such as an indicator, this is most often: A. Lamps B. hydrometer C. Synchroscope D. Flue gas analyzer E. Synchronous meter

C. Synchroscope

If the current and voltage is out of phase by 90 degrees: A. The inductance is causing line impedance B. the power factor is 1 C. The power factor is 0 D. The actual power is 1 E. The power factor can not be calculated

C. The power factor is 0

The poles in a DC machine are bolted to? A. The amarture B. Not bolted but welded C. The yoke D. Magnetic circuits E. The end bells

C. The yoke

DC generators shunt, series and compound are self exciting, this means that: A. They can withstand load torques up to 27% of full load capacity B. Correct internal reaction by commutation C. Their own armatures supply their field current D. Can not sustain starting with out a centrifugal switch E. Can be started without an outside supply of voltage

C. Their own armatures supply their field current

Most common type of industrial electrical generation? A. Single phase AC B. Single phase DC C. Three phase D. Two phase E. Two phase AC

C. Three phase

Magnetomotive force refers to? A. The ability of the coil to produce current B. Ability of amature to rotate C. The conductance of the stator D. The ability of the coil to produce flux E. The opposite of emf

D. The ability of the coil to produce flux

Hydro-station type alternators will have a shaft disposed: A. At a 90 degree angle to the electric phase B. Of 60hz AC C. Horizontally D. Vertically E. Parallel to the prime mover

D. Vertically

Cooling liquid chosen for cooling generators is often: A. Liquid hydrogen B. liquid ammonia C. Synthetic oil D. Water with low conductivity and high purity E. Water with high electrical conductivity.

D. Water with low conductivity and high purity

Alternator capacity is rated in: A. Watts B. volts C. Amperes D. kVA or MVA or kW or MW at a specified power factor E. Ohms

D. kVA or MVA or kW or MW at a specified power factor

Separately excited generator has a?

Falling load characteristic

Stator windings for large turbo-alternators are usually of: A. Segmental type B. heavy type C. Slotted type D. Precision weld type E. Bar type

E. Bar type

The end shields hold? A. Armature B. Stator C. Brushes in contact w armature D. Rotor and armature together E. Bearing housings

E. Bearing housings

The brushes between the commutator and the armature are made from? A. Soft steel B. Copper C. Graphite D. Brass E. Carbon

E. Carbon

The emf induced in a moving conductor depends on the? A. Load B. Back or counter emf C. Temp D. Counter current E. Speed of the moving conductor

E. Speed of the moving conductor

The torque produced by the armature conductors in a generator: 1. Increases w load 2. Decreases w load 3. Opposes driving torque 4. Is actual load torque A. 1,2,3 B. 2,3,4 C. 1,3,4 D. 1,2,4 E. 1,2,3,4

C. 1,3,4

Star delta starters reduce the starting current to approx: A. 50% B. 2/3 C. 1/3 D. 3/4 E. 10%

C. 1/3 of what it otherwise would be

The increase in generator output with hydrogen cooling in place of air on any particular machine has been shown to be : (assume hydrogen pressure of 3.5kpa) A. 15-30% B. 45-55% C. 20-30% D. 10-20% E. 3-7%

C. 20-30%

Synchronous motor can be ran as an alternator or motor, it has: A. AC supply connected to the stator B. DC supply connected to the rotor C. AC supply connected to the rotor D. Three phase DC connected to the stator E. Single phase AC connected in series with the stator

C. AC supply connected to the stator

To aid in starting a synchronous motor, it is supplied with a squirrel cage winding called an: A. Stator winding B. flux winding C. Amortisseur winding D. Armature winding E. Sync starter winding

C. Armortisseur winding

A capacitive load is the opposite of? A. Inductive load C. Capacitor or any capacitive circuit having a capacitance load D. Reactance E. Voltage

C. Capacitor or any capacitive circuit having a capacitance load

Speed of a squirrel cage induction motor can only be changed by: A. Increasing the current B. decreasing the current Increasing voltage C. Changing the number of poles D. Change frequency E. Insert a Synchroscope

C. Changing the number of poles

In an alternator the rotating field is obtained by exciting windings on the rotor with? A. AC power to the stator B. DC power rectified to AC three phase power C. DC power supplied through a set of slip rings D. Stationary electric charges E. DC power supplied through the armature

C. DC power supplied through a set of slip ring

The commutator: A. Is a ventilation device B. Supplies current to the excitation bindings C. Feeds the current to and from the amature D. Supports the brushes E. Supplies voltage to the coils

C. Feeds the current to and from the armature

Alternators: A. Have AC excitation on the rotor B. DC excitation on the stator C. Have a rotating armature on which a DC excitation winding is placed D. Slip rings on the stator E. Slip rings on the rotor

C. Have rotating armature on which a DC excitation winding is placed

Why would a globe type control valve be fitted with a pneumatic piston type actuator instead of a diaphragm actuator? A. If process fluid used contained dissolved solids B. If control valve used was of gate or globe type C. If force acted on valve disc is to high to be balanced by a diaphragm D. If a cage trim is used E. If a positioner is used

C. If force acted on valve disc is to high to be balances by a diaphragm

Why is a positioner used on a piston type pneumatic actuator? A. To hold valve in fully open position B. To hold valve in fully closed position C. If intermediate service is required D. To oppose air on diaphragm E. To utilize the spring action and relieve spring tension.

C. If intermediate service is required.

Static capacitors can be used to: A. Charge transformer banks B. charge alternator coils C. Increase power factor D. Decrease power factor E. Increase power factor from zero to one

C. Increase power factor

Increase in conductor temperature will? A. Start a fire B. Create a potential shorting out of fuse link C. Increase resistance in most cases D. Trap the free valence electrons and act as an insulator E. Reduce impedance

C. Increase resistance in most cases

The manner of which the two ends of the amature coil are connected to the bars of the commutator indicates the type of winding, two main types of amature windings: A. Lap and high performance B. Wave and mutual C. Lap and wave D. Persuasion and conductive E. Wave and high performance

C. Lap and wave

The distance between two sides of one coil is always approx: A. One pole pitch or 90 electrical degrees B. 90 mechanical degrees C. One pole pitch or 180 electrical degrees D. 360 mechanical degrees E. 180 mechanical pitches

C. One pole pitch or 180 electrical degrees

Free valence electrons of a conductor, when connected to the poles of a battery will move towards A. Both poles B. Neg pole C. Positive pole D. Either or both E. Cathode

C. Positive pole

List two ways butterfly valves are installed A.welded B.unions C.flanged D.wafer E. Glued

D and C Wafer and Flanged

Three point starter for DC motors has three connections, the are? 1. Line 2. Centrifugal switch 3. Field 4. Commutator 5. Armature A. 1,2,3 B. 2,4,5 C. 3,4,5 D. 1,3,5 E. 2,3,5

D. 1,3,5

Alternating current has two major advantages over direct current, they are? 1. It can be generated without the limits of commutators 2. The slip rings are eliminated 3. Current is produced in a safer manner 4. Voltage can be very easily transformed up and down for transmission 5. It's generally more practical A. 1,3 B. 2,5 C. 4,5 D. 1,4 E. 2,3

D. 1,4

Conductive materials: 1. Gain resistance while temp rises while others loose resistance 2. Have no resistance change with temp change 3.always have resistance changing directly with temperature 4. Can vary resistance directly or inversely with temp A. 1,3,4 B. 2,3 C. 2,4 D. 1,4 E. 1,2,3,4

D. 1,4

A circuit with an inductive load is usually one containing a coil or coils, very often around a magnetic core. Examples are: 1. Motor 2. Internal combustion engine 3. All prime movers 4. Generator 5. Transformer windings A. 1,2,4 B. 2,3,5 C. 3,4,5 D. 1,4,5 E. 1,2,5

D. 1,4,5

The displacement between the centres of adjacent poles are? A. 180 mechanical degrees B. 270 electrical degrees C. 90 electrical pole pitches D. 180 electrical degrees or one pole pitch E. 270 mechanical degrees.

D. 180 electrical degrees or one pole pitch

Modern turbo-alternator is almost always A. Made of stainless steel B. synchronous capability C. Stator contains zero back emf D. 2 pole design E. 4 pole design

D. 2 pole design

Voltage drop at the armature of a shunt DC motor is a percentage that normally does not exceed A. .05% B. .5% C. .9% D. 5% E. 50%

D. 5%

In order to avoid an explosive mix of hydrogen and air in the stator at times of purging or charging, what is used as a buffer? A. Nitrogen B. water C. Carbon monoxide D. Carbon dioxide E. Methane

D. Carbon dioxide

A field regulator rheostat controls the output voltage of a DC generator, this is done by: A. Varying the speed of the armature B. Producing it's own internal reactance C. Varying the impedance D. Controlling the current to the field coils E. Acting as a conductor to even out magnetic lines of flux

D. Controlling current to the field coils

All iron of the magnetic circuit is laminated to minimize: A. Back EMF B. leakage C. counter EMF D. Eddy currents E. Voltage loss

D. Eddy currents

The advantages to be gained by effective cooling of the stator windings are: A. Increased output and voltage B. longer life span of equipment C. Higher efficiency ratings D. Increased current densities in the stator copper and consequent reduction in over all mass of the machine. E. Reduction of eddy currents and back emf

D. Increased current densities in the stator copper and consequent reduction in over all mass of the machine.

The opposition to the current by the inductance is called A. Capacitive reactance B. inductive capacitance C. Reactance D. Inductive reactance E. Inductive emf

D. Inductive reactance

What is used to check phase sequence while synchronizing generators ? A. Hydrometer B. Synchroscope C. Galvanometer D. Lamps or phase rotation meter E. Phase sequence monitor

D. Lamps or phase rotation meter

There are two ways of connecting lamps for synchronizing A. Three dark, one bright B. two dark, two bright C. All dark, one bright D. One dark-two bright, all dark synchronization E. Four on off rotation, all dark

D. One dark-two bright, all dark synchronization

In a purely reactive or purely inductive circuit the current and voltage are: A. In phase B. lagging C. Leading D. Out of phase by 90 degrees E. Out of phase by 120 degrees

D. Out of phase by 90 degrees

An increase in conductor cross-sectional area will? A. Reduce voltage B. Reduce current C. Increase current D. Reduce resistance C. Increase resistance

D. Reduce resistance

Speed control is usually restricted to? 1. Series 2. Shunt 3. Compound 4. Residual 5. Impact A. 1,2 B. 3 C. 1,3,5 D. 2,3 E. 2,4

D. Shunt and compound

Capacitors consist of two conductors separated by an insulating material, they are used in? A. High voltage applications with step down transformers B. low voltage applications w step up transformers C. Gas and refinery plants and pulp and paper industry D. Telephone and radio circuits E. Transportation industries

D. Telephone and radio circuits

Body, bonnet, diaphragms

Diaphragm valves have three basic parts, they are?

Common reduced voltage starting methods: 1. Line impedance 2. Reduction voltage 3. Star-delta starters 4. Auto-correct starters 5. Autotransformer starters A. 1,4,5 B. 2,3,4 C. 3,4,5 D. 1,2,4 E. 1,3,5

E. 1,3,5

Three point starter for DC motors has connections for? 1. Line 2. Positive 3. Negative 4. Field 5. Armature A. 1,2,3,4 B. 2,3,4,5 C. 1,3,4,5, D. 1,2,3 E. 1,4,5

E. 1,4,5

In three phase power, voltages identical in magnitude are displaced from each other by: A. 270 mechanical degrees B. 360 electrical degrees C. 90 mechanical degrees D. 180 electrical degrees E. 120 electrical degrees

E. 120 electrical degrees

Compared to air, hydrogens specific heat is how many times greater than air? A. 4 B. 24 C. 6 D. 3 E. 14

E. 14

Additional hydrogen cooled advantages include 1. Moisture free circulation and reduced strain on stator windings 2. Reduced maintenance because of gas tight seal and hence dirt and moisture free casing 3. Increased capacity 4. Quieter operation 5. Simplified foundations since external fans and coolers are not required A. 1,3,4,5 B. 2,3,5 C. 2,5 D. 1,4,5 E. 2,4,5

E. 2,4,5

The yoke or frame has two main functions: 1. Induce voltage 2. Induce current 3. Act as a magnet 4. Provide stability to the guide spring 5. Mechanical construction and strength 6.act as part of the magnetic circuit. A. 1,5 B. 2,5 C. 4,6 D. 1.2 E. 5,6

E. 5 and 6

The real power in watts is the apparent power: A. Divided by the power factor B. multiplied by the reactance C. Multiplied by the power factor D. Divided by the capacitance E. Multiplied by the phase angle

Multiplied by the power factor

Free valence electrons flow from

Negative to positive

The air gaps between the poles and the armature are kept relatively?

Small