Deck 12: Wiring for Alternators

Question 1

The electrical current flowing in the alternators through conductors produces heat in the coils because of I² R losses.

Answer 1

True

Question 2

Many of the meters on generators are now in ____________________ format.

Answer 2

digital

Question 3

If there is a complete failure of the AC power, the oil switch cannot be operated from the DC source.

Answer 3

False

Question 4

Where are the control handle and indicating lamps for an oil switch and the oil switch itself located?

Question 5

The current coils of the measuring instruments mounted on switchboards are rated at a maximum current capacity of ____________________ amperes.

Question 6

What is the significance of the scale readings on the instruments of most permanent switchboard installations being graduated to include the voltage and current transformer multipliers?

Question 7

It is safe to open the secondary circuit of a current transformer when there is a current flow in the primary circuit.

Question 8

A(n) ____________________ circuit breaker is used because of the relatively high voltage of the alternator.

Question 9

How are the windings cooled in most small alternators?

Question 10

The voltage to the potential coils of instruments mounted on the switchboard should not exceed 120 to 125 volts.

Question 11

In large utility generators, ____________________ is used for cooling the alternator core.

Question 12

In some generator systems, a large diode system is installed to prevent field charge damage.

Question 13

What does the low voltage at the instruments allow maintenance electricians to do?

Question 14

What occurs if there is no system for discharging the field?

Question 15

When alternators are connected so that they are separately excited, a(n) ____________________ must be used to deliver the DC power for field excitation to multiple generators.