Electrical Flashcards
Dc system composed of
2 nicad batteries
3 tru’s
1 dc external power unit
Ac system composed of
2 idg 1 apu gen 1 inverter 1 ram air turbine 1 ac external power unit
Idg’s and apu gen are rated at
40 kva
115v ac
400 hz
3 phase
RAT POWERS
AC ESS BUSE WHEN AC 1 and 2 are not powered
Acmp 3A
What does the static inverter do
Converts. 28 v dc power from batteries to 115 v AC POWER TO SUPPLY THE standby AC bus when AC power source is unavailable
Rat is rated to
15 kva
115 v AC
400 hz
3 phase
RAT is deployed when AC power sources are not powering AC buses
It powers within
8 seconds
RAT DEPLOYMENT
The batteries power what during 8 sec deployment
Dc ESS bus and
Standby AC bus
Through static inverter
NBPT does what
Avoids electrical transient in case of power transfer on ground
Allows momentary paralleling between AC power sources
It will do this within milliseconds, if not successful it will transfer with a minimum power interruption
DC system composed of
3 TRU
2 Nicad batteries
Dc external power on ground
TRU rated to
300 amps
Primary source of DC. Power
Converts 115 v AC to 28v DC
If 1 TRU fails
Remaining tru’s will power buses if DC bus tie switch is in auto
Respective bus is powered through DC electrical network through ETC and DCTC
TRU 1 powers
5
DC bus 1 DC ESS bus1 DC gnd svc bus Hot batt bus 1 Charges batt 1
TRU 2 powers
4
DC bus 2
DC ESS bus 2
Hot batt bus 2
Charges batt 2
TRU Ess powers
1
DC ESS bus 3
What type of batteries
2 Nicad 24v 27 amp
Batteries will provide essential systems power for ___ minutes in electrical emergency. ( RAT failure)
10
When will Batt 1 (2) over temp trigger
70°c for min 2 seconds
Min batt 2 temp for apu start
-20°c
DC gpu provides power to apu start bus when plugged in, what normally powers it
Batt 2
When to use DC GPU
Batt unavailable
Batt 2 below -20°c
2 types of circuit breakers
Thermal
Electronic
CB Are located in
Cockpit walls
Icc thermal ( Mx reset only)
Electronic SPDA REMOTE( resettable through MCDU)
Elec power priority
Respective IDG
APU GEN
GPU on ground w/o APU
Opposite
Onside
Inside
Outside
Crosside
What components can be load shed
Galleys
Right windshield heat
Where are the batteries located
One is in battery compartment in nose and other is in rear fuselage behind pressure bulkhead
What are 4 things you get back on AC ESS bus when rat deploys
AC fuel pump 2
Hyd 3a
1 slat channel
1 flap channel
