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Dampers or ____ are placed on a conductor at a given distance ahead of and behind the structure

"Dog bones"

Lightning can have an electrical charge of up to ?

100 million volts

Before another section of a steel tower is placed at least ____ of the bolts must be placed and tightened on the previous section

50%

When backfilling an excavation compaction of ____ to relative density is required for granular soil

70%

Two wires off a main feeder supply current to a transformer several spans away. The voltage of the feeder at the point of take-off is 4180 volts. The resistance of the two wires is two ohms and the transformer draws 40 amperes. What is the line loss?

80v

Maximum EMF is induced when a conductor cuts a magnetic field at ? .

90 degrees

Fault current indicators are used on overhead and underground systems. FCIs trip when

A given current level is reached

An advantage to paralleling lines is ____ can share the load

A lightly loaded line

A portable generator feeding into a utility line does not share the same ___ as the utility line

Ground

To prevent tripping from active downstream components, many FCIs are built with an

High degree of immunity

A ____ fault can be a dead short or partial short circuit, depending on the impedance or resistance between an energized conductor and the object causing the short

Impedance

A ____ sleeve leaves virtually no spaces between the conductor and sleeve or between the conductor strands

Implosive

Voltage drop will ? if the current to the load is increased.

Increase

Which item listed below is not used to help cool transformers?

Insulation

To reverse rotation of a 3-phase motor, you must ___

Interchange any 2 leads

Inductive reactance is measured in

Ohms

What type of fault is a distribution system Exposed to?

Open circuit, over current, over voltage, (all the above)

Which of the following is not a kind of electrical power?

Peak power

One of the most dangerous situations a lineman can face when working on an energized circuit is

Phase to phase fault

If you are working on a downed line, fed from a single phase OCR, you should remove the OCR ___

Primary leads

An OCR control uses a(n) ____ involving the line voltage (kilovolt) and line impedance at key locations to determine the distance to a fault

Program

When joining copper and aluminum conductors always ____

Put aluminum on top

Dampers placed on a transmission line are there to counter

Resonant vibration

When checking conductor sag on an existing line ____ is the best method to use

Return wave

Always test voltage and ___ readings before making any changes to an existing customers 3 phase service

Rotation

the span that is used to calculate inital sag is called the

Ruling span

A hazard associated with applying armor rod to an energized conductor is ____

Unwinding causing cross phasing

Tower footing must be able to counter ____ and ____

Uplift and down thrust

Powder-actuated tool is used to install ___

Wedge connectors

during outages or storm restoration work ? is one of the most dangerous situations an electrical worker can be confronted with

Back feed

Manufacturers use ____ to protect the steel after the tower has been cut and drilled

Dip galvanizing

It takes as little as 50 volts to produce 50 milliamperes which can cause ___

Fibrillation of the heart

Upon what principle does a transformer operate

mutual inductance

A thumper operates by building up a ____ charge and then discharging it through the cable

Capacitive

transformer losses are referred to as ? and copper losses

Core

One method used to ground a transmission steel tower is called ?

Counterpoise

Transformers are normally loaded to ___ of their nameplate rating

125%

A 10-kilovolt ampere transformer can provide ____ for as long as 30 seconds without damage

20kva

The voltage drop per 1,000 feet of 1/0 copper wire (resistance = .122 ohms per 1,000 feet) when 40 amps of current are flowing through the wire is ?

4.88v

Back-feed can occur by electricity being transferred through a connected load and ____

By induction

The power factor is the ratio between____ and ____

Kw peak and kva peak

To protect underground distribution system a ____ class arrestor is typically used in addition to an arrestor located on the dip pole

Light duty

Two things that need to be done before using phasing equipment are to make sure the phasing equipment is working properly and

Make sure the lines are energized

Phase ___ is the order in which voltage waveforms of a polyphase AC generator reaches its respective peaks

Sequence

Voltage regulators must be accounted for and ____ prior to closing in disconnects that will tie in two circuits

Set on neutral position and locked out

Besides the use of socket wrenches ____ are the other tools normally used on steel tower construction

Spud wrenches

The most common method of sagging has been the ____ method

Target

When a helicopter is building a tower in sections ____ are placed on the tower

Temporary brackets

proper grounding and barricading is critical when using a ? to locate a fault

Thumper

The ? number on a residential meter's faceplate refers to watt-hours per turn of the disk

kH


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