ELECTRICAL Flashcards
How many TRs?
4
How many sources of electrical power?
4
Where is the ELECTRICAL POWER CENTER located?
It’s the CB panel behind the Captain’s seat
Is the AC CROSSTIE SYSTEM manual or automatic?
AC CROSSTIE SYSTEM is automatic, DC CROSSTIE SYSTEM is manual
What are the two different temperatures displayed on the CSD temperature gauges?
INNER scale: Oil Outlet Temperature
OUTER scale: Oil Temperature RISE
What temperature do the CSD temperature gauges normally read?
OUTLET temperature
What are you reading when you push the “ PUSH FOR RISE” button near the CSD temperature gauges?
Oil temperature RISE as it passes thought the CSD
How many positions on the GENERATOR CONTROL SWITCH?
Three:
On, Off and Reset
Will the ENGINE GENERATOR automatically come on line on engine star if then APU was supplying power?
Yes as long as the long as the GENERATOR CONTROL SWITCH is in the ON position
What do the AC LOAD METERS indicate?
The load that each generator is delivering to its respective AC BUS
On the AC GENERATOR LOAD METER, what is indicated by
“.5” ?
50% of RATED CAPACITY
What are the AC LOAD LIMITS?
“1.0” - “1.5” for FIVE (5) MINUTES
Greater than “1.5” for FIVE (5) SECONDS
Engine Driven Generator load limits
VOLTAGE: 115. +/- 3
FREQ. : 400 + /- 4
AC BUS X-TIE
In AUTO, what are its functions? (3)
1- Prevents paralleling of Power Sources
2- Keeps AC Buses powered
3- Isolates system faults
During normal operations, is the AC X-TIE open or closed?
Open
What are the indications when there’s a fault on a bus?
"AC CROSSTIE LOCKOUT"
"L AC BUS OFF"
"L GEN OFF"
message on the MESSAGE DISPLAY SCREEN
The AC X TIE locks openWhat is the APU BLUE POWER IN USE indicate?
APU is powering the corresponding AC BUS
Why is it necessary to place both APU BUS SWITCHES to on while on the ground?
Because the APU does not have X TIE CAPABILITIES on the ground
Does EXTERNAL POWER have X TIE CAPABILITIES?
No
ELECTRICAL SOURCE POWER PRIORITY
Respective side engine generator
APU generator
EXTERNAL power
Opposite side engine generator
Is it normal to have the following message?:
APU GENERATOR OFF
Yes, after both engines have been started
What powers the GROUND SERVICE BUS?
RIGHT GENERATOR BUS
APU on the ground
EXT. PWR on the ground
GALLEY POWER Sheds when the X-TIE closes.
T/F?
True
APU GENERATOR LIMITS
115 +/- 3
400 +/- 10
What powers the two #1 TRs?
Via the left AC BUS. Both are powered from the LEFT AC BUS
What powers the two RIGHT TRs?
#1 RIGHT TR is powered from the RIGHT AC BUS #2 RIGHT TR is powered from the GROUND SERVICE BUS
What do the DC LOAD METERS indicate?
The load that each TR is delivering to its respective DC BUS
What are the DC LOAD LIMITS?
“0” - “1.0”
LOAD DIFFERENCE of 0.3 between the two TRs on the same side
What protects against a FAULT during DC CROSSTIE OPERATIONS?
A fuse
What normally powers the DC TRANSFER BUS and the EMERGENCY DC BUS?
From the LEFT DC BUS
How many batteries?
2 14 volt batteries
In series that provide 28 volts
Where does the BATTERY CHARGER get its power from?
GROUND SERVICE BUS
Conditions for the BATTERY CHARGER to operate in a charging condition (3)
GROUND SERVICE BUS powered
BATTERY SWITCH on
EMERGENCY POWER SWITCH off
Turning the battery off removes power from: (2) (3)
BATTERY BUS
BATTERY CHARGER
If no AC power is available,
DC TRANSFER BUS
-Battery switch is on
-Both AC Electrical systems fail
Which buses will be powered?
BATTERY BUS
BATTERY DIRECT BUS
- through an automatic power transfer,
DC TRANSFER BUS
What is powered when the EMERGENCY POWER SW is turned to ON?
EMERGENCY DC BUS
-and through an INVERTER,
EMERGENCY AC BUS
What is indicated by the illumination of the
EMER PWR IN USE light?
Illuminates when the EMER PWR sw is placed to “on”
During an emergency situation, the five buses will be available for ______ minutes
30 minutes DC TRANSFER BUS BATTERY DIRECT BUS BATTERY BUS EMERGENCY DC BUS EMERGENCY AC BUS
Which DC BUS is ALWAYS powered by the BATTERY?
The BATTERY DIRECT BUS is always powered by the BATTERY
How do you power the BATTERY BUS?
By turning BATT s/w to “ON”
How do you turn off the BATTERY CHARGER?
Turning BATTERY SWITCH to “OFF”
Note: And if no AC POWER available, the DC TRANSFER BUS
If BATTERY SWITCH is on and you loose all AC POWER, which buses are still powered?
BATTERY BUS
BATTERY DIRECT BUS
DC TRANSFER BUS (Via Power Transfer Bus)
What does the EMERGENCY POWER sw powers when set to “ON”?
EMERGENCY DC BUS
EMERGENCY AC BUS ( via INVERTER)
What’s powered from the DC TRANSFER BUS?
- Fire detection and protection
- STB Horizon Indicator
- Master Warning and Caution systems
- LEFT SCREEN of OVERHEAD ANNUNCIATOR
DC TRANSFER BUS
- Fire detection and protection
- STB Horizon Indicator
- Master Warning and Caution systems
- LEFT SCREEN of OVERHEAD ANNUNCIATOR
What’s powered from the EMERGENCY DC BUS?
- Cockpit Flood Lights
- Captain’s Radios
- Captain’s Pitot Heat
What’s powered from the EMERGENCY AC BUS?
Captain’s Flight Instruments
First Officers RDMI
