Midterm Seg 4 June 24

If the primary current is less than two amperes for a transformer rated at 600 volts or less, the short-circuit protective device can be set at not more than _____ percent of this value.

• 100

• 150

• 250

• 300

Connections between the current and potential transformers in the high-voltage section of the unit substation and the autotransformer and meter sockets in the cabinet are made with size 12_______ wire.

• Copper Wire Gauge

• British Standard Wire Gauge

• Metric Wire Gauge

• American Wire Gauge

Lightning arresters are designed to provide a (n)_______ path to ground for any surge currents such as those resulting from a lightning strike.

• high resistance

• low-impedance

• non-conductive

• variable

The autotransformer is designed to provide voltage components to the potential coils of the reactive meter. These voltage components are _______ degrees out of phase with the line voltage.

• 60

• 90

• 120

• 150

After the incoming voltage is reduced to the desired value, it is taken by into the low-voltage section.

• busbars

• circuit breakers

• fuses

• transformers

The ______ of a transformer is the winding that is connected to a voltage source.

• resistor

• output

• primary

• open circuit

is the process of selecting protective devices so that there is a minimum of power interruption in case of a fault or overload.

• Insulation

• Shielding

• Coordination

• Integration

The conductors of a single phase are not permitted to be run in metallic conduit because _________ currents will be induced.

• eddy

• alternating

• direct

• residual

If you have a raceway with 35 current-carrying conductors, by what adjustment factor must you multiply the ampacity?

• 0.1

• 0.25

• 0.4

• 0.6

Twelve 14 AWG copper conductors with type RHW insulation are to be installed in conduit in an area with an ambient temperature of 110 degrees F (43 degrees C). What will be the ampacity of these conductors?

• 10.5 amperes

• 8.2 amperes

• 20.0 amperes

• 25.0 amperes