EMB7 Electrical Flashcards
What is the DC system composed ?
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 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
Ac system composed is of….
2 idg 1 apu gen 1 inverter 1 ram air turbine 1 ac external power unit
The 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
What do the batteries power during the 8 seconds whilst the RAT is being deployed?
Dc ESS bus and Standby AC bus through static inverter
What is the function of the NBPT?
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
What type of batteries?
2 Nicad 24v 27 amp
Batteries will provide essential systems power for ___ minutes in electrical emergency. ( RAT failure)
10 minutes
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 would you use DC GPU?
Batt unavailable Batt 2 below -20°c
What are the 2 types of circuit breakers?
Thermal Electronic
Circuit Breakers are located in…
Cockpit walls
Can the CB be reset by the pilots?
Icc thermal ( Mx reset only)
Electronic SPDA REMOTE( resettable through MCDU)
