Electrical Flashcards
Where is the ELEC power panel located?
The overhead panel
How are the main AC generators cooled and lubricated?
Aft trans main oil/lube system
The GCUs protect the AC system from what four conditions?
Over-voltage
under-voltage
Under-frequency (RRPM)
Feeder Fault (Short/open circuit)
Where are the No. 1 and No. 2 auxiliary PDPs located?
Cabin (mid-point)
How is the APU generator cooled?
Air cooled
An indicator on the center instrument panel indicates when the battery voltage drops
below ___ V dc.
20
What is the purpose of the AC bus-tie gang bars on each PDP?
isolate respective system and prevent “bus-tie” from occurring to the other side
With the BATT switch in OFF position, the battery supplies DC electrical power only
to the _____ bus.
Battery
The battery bus can be energized by what two sources of DC electrical power?
Battery and No. 1 DC bus
What components provide electrical power to the No. 1 and No. 2 DC buses?
Transformer rectifier
1&2
What is the order of priority for the DC electrical system from highest to lowest?
Transformer rectifier
external DC power agpu
battery
True or False? The battery switch (BATT) must be in the ON position in order to recharge or maintain the charge of the battery.
True
What three DC buses are powered by the battery with the BATT switch in the ON position?
Batt Bus
Essential 1
Essential 2
If the APU is running or external AC power is connected, DC power is supplied by
the helicopter ___.
Transformer rectifier
What is the order of priority of power for the AC electrical system from highest to
lowest?
Main AC Generators
APU Generator
External AC power
What “system” allows either main generator to provide electrical power to both buses should a single generator fail or be taken off-line?
Bus-tie system
If all three generator switches are placed to the ON position (No.1, No. 2 main, and APU) which one(s) will provide electrical power to the No. 1 and No. 2 AC buses?
Each main AC gen will provide power to its respective bus. APU gen power will not be connected to the bus
The primary active caution messages to look for in determining whether or not a
bus-tie exists are the respective RECT FAIL (OFF), ENG FUEL PESS LO, and
______________.
AFCS 1 (2) FAIL
Should both generators fail, both rectifiers will be _________.
Disabled
What will be the indication if a bus-tie DOES NOT exist when a RECT1 or RECT2
OFF becomes active?
Along with aforementioned cautions, these other respective coutions may also become active: AFCS FAIL and ENG FUEL PRESSURE LO
What indication will you have that a bus-tie DOES exist during a single generator
failure?
Should be no other cautions besides appropriate GEN caution
What is the procedure (first underlined step) for both RECT1 OFF and RECT2 OFF
cautions active?
Land as soon as possible
How many phases do the main generators have?
- Phase A, B, and C operating at 400 Hz
What kind of battery does the chinook have?
Sealed lead acid battery (SLAB)
