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A worker using a telescopic (extending) switch stick to energize equipment is 100% safe from any potential fault current when standing on the ground. Select one: True False

False

A good multi-grounded neutral is important for circuit protection on a wye system because a poor return path to the source will reduce the current in the complete circuit and reduce the current through the protective switchgear. Select one: True False

True

A protective coordination scheme provides automatic isolation of faulted circuits from the system while leaving the rest of the system in service. Select one: True False

True

Lightning causes a fault current to be generated because the high-voltage arc establishes a path of ionized air to ground. Select one: True False

True

The same current level flows into the fault, returns to the source, and returns through the protective switchgear to the fault. Select one: True False

True

There is a hazard to anyone working at a location where a ground fault results in electrical energy flowing into the earth. Select one: True False

True

When the resistance or impedance between a live conductor and another element of a different potential is low enough, ? . a.a fault occurs b.all current will flow through the larger conductor c.current flow will be blocked d.optimum circuit conditions exist

a.a fault occurs

A higher voltage circuit is more likely to trip out when a dry tree limb is in contact with the line because it is able to generate a higher fault current flow ? . a.back to the source b.that will produce circulating currents c.through lightning arresters d.to the other phases

a.back to the source

An example of a high-impedance fault is a ? somewhere on the circuit contacting a phase. a.dry tree limb b.faulted lightning arrester c.green tree limb d.truck boom

a.dry tree limb

A broken conductor lying on frozen ground is a(n) ? fault and does not provide a good path for current flow into the earth. a.high-impedence b.insulated c.intermediate d.low-impedence

a.high-impedence

A ground gradient mat protects a worker opening an air break switch because it forms a(n) ? . a.barrier to voltage b.equipotential zone c.high-resistance zone d.step potential hazard

b.equipotential zone

The total current that a circuit is able to supply to a short circuit is called ? current. a.abnormal b.fault c.nominal d.quickening

b.fault

The highest fault currents are likely to be found ? . a.at the end of the line b.near the source of a circuit c.on the line with the fewest transformers d.on the line with the highest voltage

b.near the source of a circuit

For a recloser or breaker, ? means a unit is sized with contacts and trip mechanisms large enough to interrupt the highest fault current that could occur at that location. a.coil saturation capacity b.contact travel time c.frame size d.trip speed

c.frame size

On a job site, if an underground cable is dug up or punctured, workers could be hurt because of the resulting ? . a.breaker operations b.cable capacitance c.ground fault d.hydraulic fire

c.ground fault

The magnitude of a fault current is governed by the capacity of the system, the conductivity of the circuit, and the ? . a.ambient temperature b.size of substation breakers c.type of fault d.type of fused disconnects

c.type of fault

Current that is fed to meet a customer's demand at a given moment is called ? current. a.critical load b.instantaneous demand c.intermediate d.load

d.load

Energized conductors slapping together in a long slack span due to a car accident is an example of a(n) ? . a.high-resistance event b.open circuit event c.phase-to-ground fault d.phase-to-phase fault

d.phase-to-phase fault

Voltage gradients are also known as ? . a.eddy currents b.ground spikes c.ripple emissions d.step potentials

d.step potentials

The larger the ? , the greater the ability of the system to supply a high-fault current. a.generating plant b.load being served c.physical size of circuit breakers d.transformer feeding the circuit

d.transformer feeding the circuit

The protection scheme of a high-voltage system is divided into protective ? . a.categories b.methods c.stations d.zones

d.zones