Electrical

Question 1

What is the purpose of the training product for CH-47F Electrical System?

Answer 1

To instruct international military students under specific criteria

Criteria include purchasing equipment through FMS and having an accepted clearance.

Question 2

What are the major components included in the CH-47F Electrical System?

Answer 2

Electrical component terminology, electrical system general characteristics, AC and DC power supply, power distribution system, malfunctions and emergency procedures.

Question 3

What is the risk assessment level for the CH-47F Electrical System training?

Answer 3

Low.

Question 4

List the general electrical concepts and component terminology.

Answer 4

• Switch
• Relay/Contactor
• Circuit Breaker
• Electrical Bus/Bus Bar
• Bus-Tie/Cross-Tie
• Current Transformer/Transducer

Question 5

Where is the Electrical (ELEC) Power Panel located?

Answer 5

Lower left corner of the overhead switch console.

Question 6

What does the Battery Low Indicator Light (BAT LOW) indicate?

Answer 6

Illuminates when battery voltage is less than 20 Volts DC.

Question 7

What is the Kilo-Volt Ampere Hour (KVA) measurement used for?

Answer 7

High output aviation applications requiring continuous and constant output of electrical power on demand.

Question 8

How much power does 40 KVA equate to in Watts?

Answer 8

32,000 Watts.

Question 9

What is the primary purpose of the Permanent Magnetic Generator (PMG) in the main AC generator?

Answer 9

To provide a source of electrical power for the generator control unit during normal operation.

Question 10

What conditions do Generator Control Units (GCUs) monitor?

Answer 10

• Over-voltage
• Under-voltage
• Under-frequency (RRPM)
• Feeder Fault (Short/Open Circuit)

Question 11

What is the cooling method for the APU generator?

Answer 11

Air-cooled by a built-in fan.

Question 12

What is the function of the Reverse Current Cutout Relay (RCCO)?

Answer 12

Disconnects its respective Transformer Rectifier from the DC bus and provides a signal to activate the RECT OFF caution.

Question 13

What are the internal components of the Main Power Distribution Panels that are not visible during pre-flight inspection?

Answer 13

• Contactor Relays
• Reverse Current Cutout Relays
• AC Current Transducers
• Current Transformers
• Battery Chargers

Question 14

What is the order of priority of power for the DC electrical system from highest to lowest?

Answer 14

• Transformer rectifiers
• External DC power
• Battery

Question 15

True or False: The battery switch (BATT) must be in the ON position to recharge the battery.

Answer 15

True.

Question 16

What three DC buses are powered by the battery with the Battery switch in the ON position?

Answer 16

• Battery bus
• Essential 1
• Essential 2

Question 17

What is the order of priority of power for the AC electrical system from highest to lowest?

Answer 17

• Main AC Generators
• APU Generator
• External AC power

Question 18

What system allows either main generator to provide electrical power to both buses during a generator failure?

Answer 18

The bus-tie system.

Question 19

What happens during dual generator failure in terms of electrical management?

Answer 19

Load shedding occurs for both AC and DC systems.

Question 20

What are the cautions associated with the electrical system?

Answer 20

• Single Generator Caution
• Transformer Rectifier Cautions
• Single Rectifier Caution
• Dual Rectifier Caution