3-1 test

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47.) these transformers have a secondary voltage rating of 120/240. As connected and banked, the voltage on the secondary mains is _________ ?. A. 120 from line to neutral and 208 from line to line B. 120 from line to neutral and 240 from line to line C. 208 from line to neutral and 240 from line to line D. 240 from line to neutral and 360 from line to line

A. 120 from line to neutral and 208 from line to line

25.) power factor is equal to real power divided by __________.?. A. Apparent power B. Kilowatt hours C. KVA D. Reactance

A. Apparent power

43.) if the neutral wire is cut on an energized 120/240-volt service it could result in a chock because the neutral ______ ?. A. Carries the current difference of two legs B. Is grounded C. Is in parallel with A and B phase D. Is in series with A and B phase

A. Carries the current difference of two legs

48.) when assessing a problem with a transformer bank, name two items that would help troubleshoot the problem. A. Clamp on ammeter, voltmeter B. Load chart, clamp on ammeter C. Test light, load chart D. Voltmeter, ohmmeter

A. Clamp on ammeter, voltmeter

31.) The simplest and one of the earliest of the 3-phase system is the 2,400-volt _______ .? A. Delta B. Open C. Star D. Wye

A. Delta

18.) capacitance is measured in _________ A. Farads B. Henry's C. Joules D. Watts

A. Farads

34.) underground primary connections are prone to_________ ?. A. Ferroresonance B. Reduced power factor C. Self -protection D. Transient voltage

A. Ferroresonance

14.) The measure of the number of the cycles that occur in one second is called ______?. A. Frequency B. Harmonies C. Pulse rate D. Sine wave

A. Frequency

15.) In an AC circuit, the RMS value is equal to _________ times the peak value. A. 0.637 B. 0.707 C. 1.125 D. 1.414

B. 0.707

30.) A delta system has a balanced load with 200 amperes of current flowing through each load line. The current flow through teach of the transformer windings is ______ ?. A. 100 A B. 115.6 A C. 231.2 A D. 346 A

B. 115.6 A

33.) commercial 3-phase generators to have coils mounted on the stator and are connected together as three circuits, with a _______ phase separation. A. 60" B. 120" C. 180" D. 360"

B. 120"

29.) In a wye system, the phase to neutral voltage roads 7,620 volts; what is the phase to phase voltage.? A. 12,470 B. 13,200 C. 14,400 D. 15,240

B. 13,200

37.) These transformer have a secondary voltage rating of 240/480. As connected, the line-to-line potential across the secondary wires is ________?. A. 208 V B. 240 V C. 277V D. 480 V

B. 240 V

45.) The 3 phase capacity of any closed transformer bank is always ________ times the rating of the smallest transformer in the bank. A. 2 B. 3 C. 3.5 D. 4

B. 3

11.) The wye system is also known as a _______ system. A. 3-wire B. 4 wire C. Parallel 3-phase D. Series 3-phase

B. 4 wire

49.) the load on this secondary circuit is unbalanced. The current flow through the (a) line is 40 amperes, through (b) line is 50 amperes and through (c) line is 60 amperes. The voltage across the secondary windings is 277. The total power drawn from this bank is ______ ?. (Round off to a whole number) A. 24 KVA B. 42 KVA C. 67 KVA D. 72 KVA

B. 42 KVA

23.) A_______ is a coil of cable that sets up an inductive reaction in a circuit to protect a substation during a high fault current. A. Capacitive reactor B. Current-limiting reactor C. Voltage reactor D. Shunt reactor

B. Current-limiting reactor

44.) these transformers are banked in a _______?. A. Delta-delta B. Delta-wye C. Wye-delta D. Wye-wye

B. Delta-wye

10. A practice that will reduce lost time on a job is to _______ ?. A. Come to work when sick B. Good housekeeping C. Have an entitlement attitude D. Make personal cell phone calls while in route to job

B. Good housekeeping

21.) The energy used to magnetize a transformer core is a type of _______ load.? A. Capacitive B. Inductive C. Limiting D. Resistive

B. Inductive

40.) when part of the electrical circuit carries the unbalanced current back to the source during normal operation?. A. Ground B. Neutral C. Primary D. Secondary

B. Neutral

9.) job productivity can be reduced by_______?. A. Detailed job briefing B. Personal cell phone use C. Tailboard meetings D. Visits by safety officials

B. Personal cell phone use

7.) the most effective method of identifying and communicating with unorganized worker is _____ A. a good training program B. Salting C. The local phone book D. The state license requirements

B. Salting

32.) there are two voltages available in a _______ system. A. Delta B. Triangle C. 2-phase D. Wye

B. Triangle

1). The leading factor of your success in becoming a journeyman is________ A. The AJATC B. You C. Your instructor(s) D. Your on-the-job- training

B. You

35.) This transformer bank provides both single and 3-phase power. The transformer in the middle position will supply ______ of the single-phase load. A. 1/3 B. 1/2 C. 2/3 D. All

C. 2/3

8.) the manpower cost of a job is normally figured at ______ of the total cost.? A. 20% B. 30% C. 40% D. 50%

C. 40%

27.) The time required to charge or discharge a capacitor is measured in time constants. It takes ________ time constant(s) to charge a capacitor A. 1 B. 3 C. 5 D. 8

C. 5

6.) the IBEW program that is a "call to action" based on the acute need for radical change is called the __________ A. Blueprint for change B. Blue print for the New millennium C. COMET program D. Organize Now! Program

C. COMET program

24.) The type of ______ used is an important factor in capacitor will have. A. Conductor B. Core C. Dielectric D. Resistor

C. Dielectric

2). When discussing the apprenticeship program and training, the "why" of the trade is learned________?. A. At the union hall/union meetings B. By your journeyman/ job Forman C. In the classroom D. On the job

C. In the classroom

22.) The major advantage that alternating current has over direct current system is that _______ ?. A. Fewer conductors are required B. Is has lower impedance C. It is easily transformed from one voltage to another D. It is unaffected by reactive losses

C. It is easily transformed from one voltage to another

19.) the mathematical symbol for inductance, used in calculating AC circuits is _______?. A. C B. I C. L D. Z

C. L

17.) current that flows through an inductive load will ________ the voltage. A. Be in phase with B. Have the same sine wave as C. Lag D. Lead

C. Lag

20.) The ratio of the circuits true power to apparent power is the circuits _______ ?. A. Impedande B. Inductance C. Power factor D. Total current

C. Power factor

39.) always disconnect the ______ before working on or removing the tank ground. A. Jumpers B. Neutral C. Primary leads D. Secondary leads

C. Primary leads

5.) An arrangement between the American council on educational (ACE) and the electrical training alliance (NJATC) allows graduates of the IBEW-NECA apprenticeship program to________ A. Be eligible to apply for a contractors license B. Gain for college credit C. Qualify for college credit D. Receive a college degree

C. Qualify for college credit

16.) AC circuit loads are described as inductive, capacitive, or _______ loads. A. Average B. Effective C. Resistive D. RMS

C. Resistive

4.) the three elements necessary to perform as journeyman electrical workers are knowledge, attitude, and ________ A. Ability B. Aptitude C. Skill D. Workmanship

C. Skill

42.) when paralleling two single phase transformers, both transformers must be connected _________ ?. A. To any primary phases B. To different phases C. To the same primary phases

C. To the same primary phases

36.) In this open bank the secondary _______ wire is called the high phase or wild leg. A. a B. b C. c D. d

C. c

26.) by conducting load studies, properly sizing and placing capacitors can reduce the _______ that an electrical supplier has to deliver to the customer. A. Conductor size B. kVA C. kVAR D. kW

C. kVAR

13.) By converting a 2,400 volt (delta) primary system to be 4,160-(wye) system, the capacity of the circuit can be increased by_______ A. 1.73% B. 33% C. 58% D. 73%

D. 73%

46.) A closed bank with a delta secondary has been reconnected as an open bank due to an emergency. The KVA rating of this open bank is ________ of the rating of the remaining two transformers. A. 42.3% B. 57.7% C. 66% D. 86.6%

D. 86.6%

28.) all personal that could possibly be in physical contact with a capacitor or capacitors that are being removed from service should ______?. A. Disconnect from the line B. Short out and ground the capacitor C. Wear all appropriate personal protective equipment. D. All of the above

D. All of the above

3). The responsibility for upholding the requirements of the bargaining agreement belongs to ________ ? A. Contractors B. Local union business manager C. Local union members D. All of the above

D. All of the above

41.) The primary coil on a single phase transformer connected delta on 12,470 wye volt system is would be connected _______?. A. Grounded wye B. Phase to ground C. Phase to neutral D. Phase to phase

D. Phase to phase

12.) by using the same substation transformer and adding a neutral wire, a distribution circuit has been converted from a 2,400 volt delta to a 4,160 volt wye. After conversation, the voltage across the substation transformer windings will be _______ .? A. Increased by 1.7 times B. Increased by 33% C. Reduced by 1.73% times D. Remain the same

D. Remain the same

38.) In the _______ connection, the primary and the secondary neutral must be grounded and tied together. A. Delta-delta B. Delta-wye C. Wye-delta D. Wye-wye

D. Wye-wye


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