Electrical Flashcards
What does the IDG amber LED indicate?
Which IDG must be disconnected.
What doe turning the IDG switch to OFF do?
Opens the IDG contractor isolating the IDG from the AC BUS
What does turning the IDG switch to DISC d?
mechanically disconnects the IDG (cannot be reconnected in flight)
How are the DC ESS busses powered in the event of a complete AC power loss and prior to RAT deployment?
Aircraft batteries via the Hot BATT busses 1&2
What is the minimum speed if the RAT is deployed?
130 KIAS
Which busses will the RAT power?
Essential busses
Can the RAT be manually deployed?
yes
Can the RAT be stowed in flight?
no
Can the RAT handle the same electrical load as the IDGS?
no
When does the RAT automatically deploy?
when AC busses are not powered
How long does it take for the RAT to deploy?
8 seconds
Which HYD pump operates when the RAT is deployed?
HYD pump 3A
What powers the APU start bus?
Batt2
What is the source priority for powering the airplane?
Rspective IDG (onside)
APU. (inside)
GPU (outside)
Opposite IDG (cross side)
What do the TRUs do?
converts AC power to DC
What do you expect to happen if the parking brake is released with the GPU connected?
EICAS caution message and a “GPU connected” aural warning.
Can the aircraft be powered using the DC GPU?
no
How are the batteries charged?
through the TRUs
What is the purpose of the AUTO function on Batt2?
system logic allows it to control the APU start bus or the DC ESS bus.
How long will the Aircraft batteries las on emergency power if the RAT Does not deploy?
10 minutes
