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Lineman Apprentice Test Questions with Complete
Solutions
The difference in a 3 wire & 4 wire distribution circuit is? Correct Answer-the Neutral wire What is the formula for power Correct Answer-P=VxI Transmission voltage is generally _________ to _________. Correct Answer-138,000 to 765,000 volts If the diameter of the pole to be set is 10", the diameter of the hole should be ____ to allow sufficient room for tamping. Correct Answer- 16", 3" on each side of the pole What are the component parts of a distribution system? Correct Answer- Distribution Substation, feeder circuits, switches, protective equipment, primary circuits, distribution transformers, secondaries, services. An advantage of a Wye Primary system over a Delta primary system is? Correct Answer-Increased power carrying capacity, better voltage regulation The total flow of current from a generating plant may be as large as __________ amps. Correct Answer-20,
How many Amps does a 120 volt, 60 watt incandescent bulb draw? Correct Answer-.5 amps, P=IxE I=P/E 60/120=. Thury system was generators connected in ______ to transmit ________ amps at max voltage of _______ volts? Correct Answer-Series, 150 amps, 27,000 volts An aluminum wire must be ________ times as big as copper is a cross section to have the same conductivity. Correct Answer-1.66 (this means that aluminum is only 2/3 as conductive as copper) Slices should not be installed ________ ft from a tie wire or armor rod. Correct Answer-1 ft (12") Bolted connections may be used when? Correct Answer-If the wires to be connected are not under tension When splicing distribution wires, how far should the line be laid out straight before splicing? Correct Answer-10 ft The head of a hydraulic operated tool weighs approximately ________ lbs. Correct Answer-15 lbs (tools operate w/ a pressure of 10,000 psi)
DC Transmission was initiated in ______ during the year _______ Correct Answer-Germany, 1883 What device changes AC to DC? Correct Answer-Commutator (the process is called commutation) The Maximum use voltage for class 3 gloves is _______ volts Correct Answer-26,500 volts The size of a crew needed to pike a 30 ft pole is _______, 35 ft _______, 40 ft _______, 45 and 50 ft _______ Correct Answer-6 (30 ft), 7 (35 ft), 8 (40 ft), 10 (45 &50 ft) True or False- When applying a splice on wire, the wire should be straight for a distance of 10' Correct Answer-True Which 2 voltage types on Transmission lines require a corona shield? Correct Answer-Extra and Ultra High Voltage (shields are at each point of conductor support) A ground rod that penetrates perpetually moist earth will have a fairly ________ resistance. Correct Answer-Low XLPE=______ Correct Answer-Cross linked polyethylene
EPR=_________ Correct Answer-Ethylene, Propylene, Rubber Current lags voltage in ______ devices, current leads voltage in ________ devices. Correct Answer-Inductive, capacitive True or False-Distribution transformers should be installed as close as possible to the center of the load that it's feeding. Correct Answer-True A swiss engineer named _____________ developed a high voltage DC transmission system in _____________. Correct Answer-Thury, 1899 True or False- The top of your climbers should be approximately 4 in below the inside prominence of the knee joint. Correct Answer-False (hooks are adjustable in 1/2 in increments 14-20 inches) ____________ designed and buried a transmission system using copper rods insulated with jute. Correct Answer-Thomas Edison Before lowering a victim to the ground, 2 rescue breathes should be given so that the throat tissue has less of a chance of swelling shut and the heart will be more likely to keep beating. Correct Answer-Yeah do that.
Bolted or squeeze-on connections may be used where the line is slack. Correct Answer-True In transmission, it is sometimes necessary to first splice steel core, then splice the outer alum wires. When finished, the outer splice is filled with _______ _________ to prevent oxidation of the splice. Correct Answer- Zinc Chromate Automatic splice is used where one expects to have 15% of the rated breaking strength of the conductor. Tension should be applied at all times or else the jaws may release and allow the conductor to drop out. Correct Answer- By using a popsicle, what problem is eliminated? Correct Answer-Cold flow problems of a stranded alum conductor in a copper clamp (such as a tank ground or hot line clamp) When choosing the order of conductors when making connections, in which order should copper and alum be placed? Correct Answer- Aluminum over copper When using armor rods, the attachment of the conductor to the insulator should be in the middle of the armor rod. Correct Answer-
What is the most commonly used and simplest tie to use? Correct Answer-Western union Lines with less than 5,000 volts are generally covered with what different types of materials? Correct Answer-Triple braid weather proof cotton, Neoprene, Polythene The current usually ____________ the voltage (leads or lags) Correct Answer-Lags A wire tong is used to ____________. Correct Answer-Hold energized wire away from work area Steel wire is a poor conductor with __________ to ___________ of the conductivity of copper. Correct Answer-10-15% Cable lube reduces the friction between the cable and duct walls by as much as _______% Correct Answer-70% Cadmium-Sulfide cell "photo cells" has a resistance of __________ when dark. Correct Answer-15,000,000 ohms The need for apprenticeship training was recognized in the _________. (1910s, 1920s, 1930s or 1940s) Correct Answer-1930's
Each time a cutout fails, some of the fiber inside the cutout barrel is eroded away. The larger the value of current interrupted, the more material that is consumed. Correct Answer- __________ reduces the tensile strength of wires. Correct Answer- Annealing Compression sleeves are mfg. for transmission line ACSR conductors that contain a gripping unit that is __________ to the aluminum sleeve. Correct Answer-internal The power factor is usually ___________ to _________ lagging. Correct Answer-.70 to 1. A _________ semiconductor can be used as a current rectifier. Correct Answer-Diode The pulsating of the output voltage in a circuit can be eliminated by adding a ____________. Correct Answer-Capacitor Voltages 69,000 to 230,0000 are classified as ________ or __________ voltages. Correct Answer-High or Tansmission
What kind of diode semiconductor can be used as a voltage reference in a an electric circuit? Correct Answer-Zener diode 1 KW is equal to about ________ hp. Correct Answer-one and 1/3 or
What are the three loading districts when talking about wire? Correct Answer-Heavy, Medium, Light When an alternating voltage and the current that causes it to flow rise and fall at the same time, the two are said to be "in phase" and the power factor is __________. Correct Answer-Unity Proper measurement for the D-ring size is the distance around the back of the body @ the point where the belt will be worn between the prominent points of the hip bones plus __________ inch. Correct Answer- In general, the bending radius "R" of the revers curves in the lead covered cables must be not less than _______ times the overall diameter of the cable. Correct Answer- The recommended pole setting depth for a 45 ft pole in rock is _________. (4 ft, 4.5 ft, 5 ft, or 5.5 ft) Correct Answer-4.5 (10%)
True or False - Capacitors and transformers are nearly identical in their operation. Correct Answer-False True or False - Grease on conductors can cause generation of corona. Correct Answer-True What is an atom called with no free electrons? Correct Answer-Insulator N- Type semiconductor - _________ number of electrons. Correct Answer-Excess P - type semiconductor - __________ number of electrons. Correct Answer-Deficient An insulator made from synthetic material such as silica or fiberglass weighs what percentage of the insulators they replace? Correct Answer- 5-10% The semiconductor blocks in a lightening arrestor are made using what type of material? Correct Answer-Zinc Oxide Material The most energy efficient transformer cores are constructed with _______ or _________. Correct Answer-Low loss cold rolled silicon strips, amorphous steel alloy strips.
In transformers how much more efficient are amorphous metal cores than laminated steel cores? Correct Answer-60% True or False - DC circuits have no lead or lag in current versus voltage. Correct Answer-True True or false - When free electrons in a conductor give up their random movement and flow in one direction, it is called current of simple current. Correct Answer-True DC cable insulation must be thick enough to provide a safety factor of ______ to ______. Correct Answer-3 to 5 True or False - The primary or high voltage side of a transformer (OH/UG) has a high electric pressure and the current is large. The secondary or low side has a low pressure and the current is small. Correct Answer-False (High side has high pressure and low current. The low side has low pressure and high current) Insulink splice colors: Correct Answer-#10=brown, #6=blue, #4=orange, #2=red, 1/0=yellow, 4/0=pink What is the breaking strength of 5/16 utility grade guy wire? Correct Answer-6,000 lbs
windings turns in steps of ____% of the rated voltage. Correct Answer- 2.5% Voltages over _____ volts are classified as experimental voltages. Correct Answer-1 million What size tie wire should be sued to tie in conductors that are #4 and smaller, 1/0 to #4, larger than 1/0? Correct Answer-#6, #4, #2 (tie wire should be soft drawn) What are the five classes of rubber goods? Correct Answer-0- The 5 steps to guy installation are: Correct Answer-Install the anchor, insert strain insulator or ground guy or both, fasten to pole, tighten guy wire and connect to anchor, mount the guy wire guard. When tying knots, the part of the rope that is looped so that the ropes lie alongside each other is called what? Correct Answer-Bight Wire insulation is generally made of these 3 materials ________, __________, _________. Correct Answer-Rubber, polyethylene, polyvinylchloride True or False - Arresters contain semiconductor blocks or discs that allow large currents to pass harmlessly to ground. Correct Answer-True
Feeders generally operate from ________ to ________. Correct Answer- 2400 volts - 34,500 volts Subtransmission sunstations generate at a range of _________ to _________ and are located close to __________. Correct Answer-34. kV-69 kV, High load (urban areas) DC circuits usually consist of ________ wires. Correct Answer-2 wires The usual generation voltage of a generation station (power plant) is _________ to _________. Correct Answer-13,200 volts - 25,000 volts, also 24,000 volts The breaker in a substation is installed between the __________ & the ___________. Correct Answer-Low voltage bus (distribution feeder voltage) & the distribution feeder circuit. True or False - Cold flow is a term used to describe load encountered when you first energize a line. Correct Answer-False A ________ can be used in a circuit to amplify a signal. Correct Answer-Transistor
Circuit Switcher - operation of circuit switchers is initiated by manually operating switch, by a remote supervisory control, or by relays that automatically sense predetermined system or equipment conditions or electrical failure (faults). Correct Answer- True or False - Voltages of 1 million volts or more are classified as ultra- high voltages or experimental voltages. Correct Answer-True The optimum insulating SF6 gas pressure is _________ psig. Correct Answer-50 psig True or False - Large single phase motors have a much smaller drain on voltage at start up than do three-phase motors. Correct Answer-False Alumoweld guy cable, seven-strand #8 has a minimum breaking strength of _______ & #% has a breaking strength of _________. Correct Answer-#8 - 15, #5 - 27, If a power transformer does not have auto tap changing underload equipment, it is usually necessary to install _________ __________. Correct Answer-Voltage Regulators Lightening arresters in a substation protect the sub from lightening strokes and surges from switching. Correct Answer-
What are the 3 most important factors to consider when choosing a conductor? Correct Answer-Line voltage, mechanical strength, amount of power to be transmitted. By changing a distribution system from Delta to Wye you will increase the load carrying capacity by ______% Correct Answer-73% DC transmission circuits are economical whenever overhead lines extend over _____ miles, or when UG circuits extend over ______ miles. Correct Answer-400 OH, 20 UG A three phase transmission system requires only ______ the total weight of conductor required for a single or two phase system. Correct Answer- 3/ True or False - Motors operating off of three-phase are much cheaper and more satisfactory than single or two phase motors. Correct Answer- True If one transformer of a closed delta bank is removed during an outage to restore service, the remaining two can handle ______% of the original capacity. Correct Answer-58%
