Study info

Question 1

T or F After a DC test has been completed on a long cable, it is most important that the conductor under test be grounded for a sustained period of time.

Answer 1

Answer: True

Question 2

T or F Single conductor, 750 kcmils core-flex services are normally grounded at both ends.

Answer 2

Answer: True if high voltage otherwise False

Question 3

T or F Before an SCR is fired, it acts like an open circuit

Answer 3

Answer: True

Question 4

T or F An SCR can only be fired if the polarity on the anode is negative with respect to the cathode.

Answer 4

Answer: False

Question 5

T or F On a DC drive with the potentiometer adjusted so that the DC motor is turning at minimum speed, the firing angle of the SCR is zero degrees.

Answer 5

Answer: False

Question 6

T or F High voltage DC lines are not subject to corona.

Answer 6

Answer: False

Question 7

T or F Single conductor 25 KV URD cables are normally tested at 55 KV.

Answer 7

Answer: False

Question 8

T or F the autotransformer can be used for starting large motors to increase Torque.

Answer 8

Answer: False

Question 9

T or F Dynamic braking on a three-phase AC motor is impossible.

Answer 9

Answer: False

Question 10

T or F Three-phase rectifiers always employ six diodes in their construction.

Answer 10

Answer: False

Question 11

T or F P.I.V. Is a term used when talking about the forward voltage drop of solid-state devices.

Answer 11

Answer: False

Question 12

T or F Three-phase bridge rectifiers are normally connected star supplies for full wave operation.

Answer 12

Answer: False

Question 13

T or F Single conductor URD cables are normally grounded at both ends.

Answer 13

Answer: True

Question 14

T or F By code, high voltage means 750 Volts or over

Answer 14

Answer: False 751 Volts

Question 15

T or F On a stress cone the finishing tape is normally wrapped by starting at the lug and taping toward the cone.

Answer 15

Answer: False

Question 16

T or F The total capacitance of a circuit containing a 20 uF and a 30 uF capacitor connected in series is 50 uF.

Answer 16

Answer : False

Question 17

T or F There is more line current drawn by a fully loaded five horse power 0.9 PF motor than a 0.7 PF horse power motor.

Answer 17

Answer : False

Question 18

T or F DC hipot testing is normally done after the cable has been in service for 5 years.

Answer 18

Answer: False

Question 19

T or F The power factor of a three-phase squirrel cage motor is better at no load than at full load.

Answer 19

Answer: False

Question 20

T or F URD concentric neutral high voltage cables are used only on three-phase power circuit.

Answer 20

Answer : False

Question 21

T or F Hypot testing is the only method of testing high voltage equipment.

Answer 21

Answer : False

Question 22

T or F “Pot heads “ are found only on three conductor P.I.L.C. cable.

Answer 22

Answer: Fasle

Question 23

T or F A fully charged lead acid batter will have a relative density of 1.125

Answer 23

Answer: False

Question 24

T or F With a large hard disk drive it is not necessary to back up any file.

Answer 24

Answer: False

Question 25

T or F In a nurse call system the reset button is located where the incident has happened.

Answer 25

Answer: True

Question 26

T or F Windows XP is an operating system that is newer than Windows 8 .

Answer 26

Answer: False

Question 27

T or F Connecting a capacitor in parallel with an inductive AC load will change the line current without affecting the load current.

Answer 27

Answer: False

Question 28

T or F The speed of a synchronous motor can be controlled by changing the rotor resistance.

Answer 28

Answer: False Nope it's false

Question 29

T or F The purpose of a thermocouple in a gas furnace is to indicate the presence of a pilot flame.

Answer 29

Answer: True

Question 30

T or F The secondary voltage of a delta/wye three phase transformer is in phase with the primary voltage.

Answer 30

Answer: True

Question 31

T or F A resistor has 3 orange bands, it is a 33 kilohms resistor.

Answer 31

Answer: True

Question 32

T or F Every 12 revolutions an 8 pole field will generate 48 cycles in a stator winding.

Answer 32

Answer: True

Question 33

T or F An alternator with 6 pairs of poles generating at 60 Hz would be driven at 600 RPM.

Answer 33

Answer: True

Question 34

T or F The power of a half-wave single-phase DC circuit can be determined by : ( EDC X 1.11)X(IDC X 1.11) =watts

Answer 34

Answer: False

Question 35

T or F An “Inductive” load is supplied from an AC source. The current (I) maximum is 310 amps. Voltage (E) maximum is 140 Volts. The effective power In KW supplied to the load is 21.7 KW.

Answer 35

Answer:True

Question 36

T or F Reactors may be used for limiting fault current surges.

Answer 36

Answer: True

Question 37

T or F A capacitor put across a set of contacts used in an inductive circuit will act as an arc suppressor.

Answer 37

Answer: True

Question 38

T or F A 20 kilohms/voltmeter has an insertion circuit resistance of 6 megaohms when switched to a 300 volt scale.

Answer 38

Answer: True

Question 39

T or F In a series DC circuit containing resistance and capacitance, increasing the capacitance increases the charging time.

Answer 39

Answer: True

Question 40

T or F To change rotation of any three phase induction motor you simply interchange any two rotor leads.

Answer 40

Answer: False

Question 41

T or F In a FA system, an E.O.L. ( end of line resistor) is required for electrical supervision.

Answer 41

Answer: False

Question 42

T or F Power cords have only one proper end to which a power plug may be installed.

Answer 42

Answer : True

Question 43

T or F The volt amps at the primary of a transformer are greater than the wattage is the secondary.

Answer 43

Answer: False

Question 44

T or F All three-phase AC motors must have overload protection set at 125% of full load current.

Answer 44

Answer: False

Question 45

T or F A 20 and 30 uF capacitor are parallel connected to a 200 volt high frequency line. If the total line current to the capacitors is 3 amps, there will be close to 1.9 amps in the 30 uF branch.

Answer 45

Answer: True

Question 46

T or F The anode is a silicon diode is symbolized by a bar.

Answer 46

Answer: False

Question 47

T or F Pull boxes used in straight runs of #35 or larger conduit containing 3- #3 R 90 XLPE, shall have a length of at least six times the internal diameter of the conduit.

Answer 47

Answer: True

Question 48

T or F Amortisseur windings are used to prevent hunting of synchronous alternators.

Answer 48

Answer: True

Question 49

T or F In general semi conductor material has a positive temperature coefficient.

Answer 49

Answer: False

Question 50

T or F A thermistor is a power resistor.

Answer 50

Answer: True

Question 51

T or F It is possible to read the wattage of a balanced three-phase three-wire load employing the two wattmeter method.

Answer 51

Answer: True

Question 52

T or F In a heat pump the flow of refrigerant can be reversed to supply heating as well as cooling.

Answer 52

Answer: True

Question 53

T or F When synchronizing AC alternators with the three dark method a considerable difference in voltage could exist even though the lights are dark.

Answer 53

Answer: True

Question 54

T or F When the frequency to a three-phase Induction motor is reduced by 10% the motor speed will be reduced by 10%

Answer 54

Answer: True

Question 55

T or F Two 100 KVA transformers connected in open delta will deliver a maximum of 115.4 KVA to a load.

Answer 55

Answer: False

Question 56

T or F The capacitors in a rapid start ballast are for radio interference and power factor correction only

Answer 56

Answer: False

Question 57

T or F A diverted rheostat is connected in a series with the series field of a DC generator.

Answer 57

Answer: False

Question 58

T or F Field discharge resistors in a synchronous motor starter are used to limit field current.

Answer 58

Answer: True

Question 59

T or F Disconnects are used with high voltage circuit breakers to provide visible proof of voltage isolation.

Answer 59

Answer: True

Question 60

T or F The purpose if an end of line resistor (EOL) in a supervised fire alarm system is to short circuit the detection devices.

Answer 60

Answer: False

Question 61

T or F Line loss is found by multiplying the voltage drop and the line current.

Answer 61

Answer: True

Question 62

T or F The most common word size for a PLC is 2 bytes.

Answer 62

Answer: True

Question 63

T or F A PLC user memory is factory configured and cannot be changed.

Answer 63

Answer: True

Question 64

T or F A thermocouple is an example of a discrete I/O

Answer 64

Answer: False

Question 65

T or F Fail safe wiring refers only to motor control stop circuits.

Answer 65

Answer: False

Question 66

T or F A PLC can use a 4-20 ma signal as an input ?

Answer 66

Answer: True

Question 67

To reverse the direction of rotation for a single-phase, shaded pole motor, the : A.) stator must be removed and turned over B.) shading coil must be interchanged C.) starting winding must be interchanged D.) running winding must be interchanged

Answer 67

Answer: A. Stator must be removed and turned over.

Question 68

The single-phase, AC series motor has characteristics which are very similar to the : A.)universal motor B.)wound rotor motor C.) AC squirrel-cage motor D.) AC induction motor

Answer 68

Answer: A. Universal motor

Question 69

Which of the following statements is true in Boolean algebra: ``` A. A•B= A+B B. — — = ——— A•B A•B C. —— —— A= A D. —— + —- = ——— A. B A+B ```

Answer 69

Answer : C. A = — — A

Question 70

The type of light transmitted in most fibre-optic communications system is:

Answer 70

Answer: Infrared

Question 71

The greatest drop output voltage will occur if full load is taken from an alternator at: A.)unity power factor B.) high leading power factor C.) low leading power factor D.) high lagging power factor

Answer 71

Answer: B. High leading power factor .

Question 72

When a capacitor is charged, the dielectric has : A.) a surplus of electrons B.) a deficiency of electrons C.) the same number of electrons

Answer 72

Answer: C. The same number of electrons.

Question 73

``` The best method of controlling the speed of a series motor is to: A.) change the load B.) vary the current to the motor C.) vary the position of the brushes D.) add a brake drum ```

Answer 73

Answer: B. Vary the current to the motor

Question 74

A DC series motor will run away if the load is removed while the power is still being applied. This is a result of: A.) loss of C.E.M.F B.) low input voltage to the armature C.) increased C.E.M.F. acting to weaken the field. D.) high voltage developed across the field.

Answer 74

Answer: A.loss of C.E.M.F. Nope it's C

Question 75

In a delta-star step down transformer bank each transformer has a turns ratio of 2:1 The primary voltage is 480 Volts and the unit supplies a 10 KW, three-phase load at unity power factor. The secondary line current is: A.) 13.9 amps B.) 12 amps C.) 24.1 amps D.) 36 amps

Answer 75

Answer:C 24.1 amps

Question 76

HRC fuses are filled with silica to: A.) make the fuse operate at a lower temperature B.) speed the rate at which the fuse element melts. C.) reduce arcing when the fuse element melts D.) to give a longer time delay

Answer 76

Answer: A. make the fuses operate at a lower temperature. Nope it's C

Question 77

If the output voltage of an alternator drops due to heavy loading it is generally brought back up by : A.) increasing the resistance is the field rheostat B.) decreasing the resistance of the field rheostat C.) increasing the speed D.) decreasing the speed

Answer 77

Answer: C. Increasing the speed Might be B

Question 78

A receptacle located in a hospital and connected to the essential electrical equipment shall be : A.) of the Class “A” GFCI type B.) approved as hospital grade displaying a green dot or triangle C.) orange in colour D.) red In colour

Answer 78

Answer: D. Red in colour

Question 79

Starting resistances of DC motors are connected: A.) In the series with the line B.) In series with the armature C.) In series with the shunt field D.) In parallel with the series field

Answer 79

Answer: B. In series with the armature

Question 80

To determine the state of charge of a nickel-cadmium battery, you could use a : A.) voltmeter with a load connected to the battery B.) hyrdrometer C.) ammeter with a load connected to the battery D.) voltmeter to measure the open-circuit voltage

Answer 80

Answer: B. Hydrometer

Question 81

The specific gravity of the electrolyte in a fully charged nickel-cadmium battery is usually about: A.) 1050 B.) 1100 C.) 1150 D.) 1200

Answer 81

Answer: D. 1200

Question 82

Emergency systems should be tested: A.) once a week B.) once a month C.) Once every 6 months D.) Once a year

Answer 82

Answer: B. Once a month

Question 83

A NO-LOAD terminal voltage of a fully-charged, six cell nickel cadmium battery would measure as: A. 6 volts B. 12 volts C. 13.2 volts D. 7.2 volts

Answer 83

Answer: D 7.2 volts

Question 84

A disadvantage of a PV (photovoltaic) system is : A.) Initial Cost B.) Maintenance Cost C.) Reliability D.) Mobility

Answer 84

Answer: A. Initial Cost

Question 85

The following loads are fed from a 600 volt, three-phase, 60 Hz source: 10 kW of electric heating, 20 kW at 0.6 Pf lagging, 15 KVA at 0.8 Pf leading, and 50 KVA at 0.65 Pf lagging. Total KVA Total KVARS System PF Total KW Line Current The KVARS rating of a capacitor bank to bring the system power factor to 0.955 The capacity of ONE capacitor in microfarads connected Delta _____ WYE________

Answer 85

``` Answers Total KVA =93 KVA Total KVARS= 55.67 KVars System PF = .8012 Total Kw = 74.5 KW I Line =89.49 A KVARS to bring PF to .955 =32.53 KVAr Capacitor connected Delta = 79.967 uF WYE= 239.1uF ```