Electrics Flashcards
What does the AC system comprise of?
2 IDGs
1 APU
1 inverter
1 RAT
1 external AC source
What does the DC comprise of?
2 NiCd batteries
3 TRUs
1 external DC source
What are the limits for the IDG oil pressure?
140psi (+/-25psi)
What are the limits for the IDG oil temperature?
168 Celsius (+/- 5)
What happens when IDG oil pressure or temperature become out of limits?
The amber LED light next to the IDG selector knob illuminates
How is manual disconnection fo the IDG achieved?
Holding the respective IDG knob to the disc for one second (max 3 seconds)
What is the rating of the IDGs and APU gen?
40kVA, 115 V AC, 400Hz, 3 phase
When does the APU come online?
3 seconds after 95% RPM has been achieved
When does automatic IDG disconnection occur?
When IDG oil temp reaches 185.6 celsius
How long does the RAT take to power up?
8 seconds
During the 8 seconds it takes for the RAT to power up what powers the DC ESS BUSES and STBY AC BUS?
The batteries
What is the minimum speed for the RAT?
130kts
What is a no break power transfer? (NBPT)
Avoids electrical transient in case of power transfer by momentarily paralleling two AC power sources
How long can the main batteries supply essential loads?
10 mins
When does the BATT 1/2 OVERTEMP warning message appear?
Whenever battery temperature reaches 70 Celsius for at least 2 seconds
