Deck 2: The Unit Substation

Question 1

Rate reductions are made by the power company when the metering measurements are taken on the side of the transformer.

A) high-voltage
B) variable-voltage
C) low-voltage
D) secondary bus

Answer 1

A

Question 2

The decimal impedance in a transformer is found by determining the ratio of the source voltage as compared to the rated voltage of the winding.

A) high-voltage
B) variable-voltage
C) low-voltage
D) short circuit

Answer 2

A

Question 3

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

A) Transformation
B) Masking
C) Coordination
D) Correlation

Answer 3

C

Question 4

The rates charged by the power company for the energy used are based on the readings of the meter registers and the indicators.

A) maximum demand
B) short circuit
C) terminal
D) ampere

Question 5

High-voltage fuses are available with either an N or a(n) rating.

A) B
B) C
C) D
D) E

Question 6

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.

A) 100
B) 200
C) 300
D) 400

Question 7

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.

A) Music Wire Gauge
B) US Steel Wire Gauge
C) W&M Wire Gauge
D) American Wire Gauge

Question 8

How do you select a fuse with the correct continuous current rating to provide transformer protection?

Question 9

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

A) busbars
B) grounding buses
C) terminals
D) secondary buses

Question 10

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

A) ammeter
B) secondary
C) primary
D) short circuit

Question 11

What should you be wary of when coordinating high-voltage fusings?

Question 12

An alternative to grounding the secondary is to let it ; that is, the secondary remains ungrounded.

A) sink
B) float
C) surface
D) exit

Question 13

A device called a provides a reliable method of terminating a high-voltage cable.

A) lighting arrester
B) pothead
C) grounding bus
D) secondary bus

Question 14

The step-down transformers, metering, and switching equipment necessary to supply the low voltage loads to the customer are housed in a .

A) unit substation
B) grounding bus
C) terminal
D) secondary bus

Question 15

What is the procedure for terminating an incoming high-voltage cable?

Question 16

A 600-volt to 200-volt transformer would become a 600-volt to -volt transformer if the connections were reversed.

A) 100
B) 300
C) 1200
D) 1800

Question 17

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.

A) 45
B) 90
C) 180
D) 270

Question 18

Discuss the role and location of the grounding bus.

Question 19

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

A) high impedance
B) low-impedance
C) indirect
D) intermittent

Question 20

What role do taps play?