Electrical Flashcards
How many batteries power the airplane?
Two
What type of batteries?
Lead-Acid
Where are the batteries located?
1 in the nose, #2 behind right wing root
Battery volts and amps.
24VDC
#1 34 Ah
#2 48 Ah
Which battery provides power for starting?
2
Minimum voltage for starting?
24 Volts
Minimum voltage for charging?
27 Volts
How many generators
Two
Generator voltage
28 VDC
Generator amps?
400 amps
Generator load limits
330A on ground
390A in air
Minimum battery temp for normal ops?
-10C (14F)
What function in the electrical system allows the engine to start without causing surges in the avionics?
Quiet start contactor
If a single generator fails in flight, what happens?
Both SHED BUSES lose power
What does it mean if the GPU is plugged in, but there is no GPU AVAIL light illuminated on the button?
DC power requirement between 25V-30V is not being met.
What are we looking for when we push in the electrical emergency button on the after start checklist?
That both batteries show at least 23.5 volts
(The generators continue to power the DC busses in this scenario, but certain
other relays open in order to confirm battery voltage).
If the GPU is powering the airplane, when do the generators come on line?
When the GPU is disconnected (from the Central Bus) which can be confirmed on
the electrical synoptic page.
If the GPU is connected and the Electrical Emergency Button is pushed in, what
happens?
Because the generators are not on-line yet, the electrical system is forced into
electrical emergency, connecting the batteries directly to the emergency buss.
(The GLC 1, GLC 2, SBC 1 and SBC 2 will be commanded to open, and BTC 1 and
BTC 2 will be hardwire locked out, EBC 1 will open and EBC 2 will close).
The Batteries 1 and 2 will supply power to the HOT BATT BUSES, EMERGENCY BUS
and the CENTRAL BUS.
If a Dual Generator failure occurs in flight, what remains powered?
The aircraft wiring logic will automatically configure the electrical emergency
scenario. The Batteries 1 and 2 will supply power to the HOT BATT BUSES,
EMERGENCY BUS and the CENTRAL BUS providing engine starting.
How long do the batteries provide power in a dual gen failure?
45 Minutes max
If while in flight, the CAS message ELEC XFR FAIL appears, what is the
memory item and why is this procedure necessary?
ELEC EMER BUTTON…………PUSH IN
A complete in-flight loss of the main generating system has occurred, but the
automatic transfer logic has failed to configure the electrical emergency condition,
so pushing in the button allows the pilot to override the automatic transfer failure
and enable the load shedding process by forcing the system into the electrical
emergency condition.
What is normally powered by Starter Generator 1?
DC BUS 1, SHED BUS 1, EMERGENCY BUS and HOT BATT BUS 1.
What is normally powered by Starter Generator 2?
DC BUS 2, SHED BUS 2, CENTRAL BUS, HOT BATT BUS 2.
