Electrics Flashcards
When the Battery Master is selected on, what bus(es) will be powered?
L/R ESS buses + AC inverters
how many temp sensors are there per battery?
2
MAIN BATT HOT
Main battery internal temp over 65deg. Turn the charging to this battery off and monitor temp.
If it continues to rise then land immediately
What is the fixed AC system primarily used for?
Avionics and flight instruments
How many inverters need to be operational to power the system?
1
What selections are available for the aux inverter and where is the aux inverter connected to the system?
Primary, off, Secondary.
L MAIN bus
What lights are powered directly by the battery bus?
Dome lights and boarding lights
How many batteries does the aircraft have?
2 24v Nicad batteries in the nose
What buses will have power with the Batt master on and the main battery on and main tie connected?
L/R ESS and L/R MAIN buses
how do we get power to the L MAIN bus on the ground (no engines)?
Main bus tie
What voltage should we see on tthe DC monitor when external power is connected?
28V
Which buses will be powered with DC external power plugged in?
All DC buses
Will external power charge the batteries?
Yes if GPU voltage higher than battery voltage
Will the APU charge the batteries?
Yes if GPU voltage higher than battery voltage
Min voltage for engine start on batteries?
22V
At what voltage does over voltage protection lock out external power?
31.5V
Can external power and the engine DC gens be on line at the same time?
No, External power is sensed by the GCU which automatically turns off the DC gens
If a DC gen fails, will the opposite main bus be powered?
Yes through the main bus tie (bus tie logic)
How are DC gens cooled?
Air cooled
What are the DC gen load limits on the ground and in the air?
- 7 on the Ground
1. 0 in the air
If the Main buses are powered, are the essential buses automatically powered?
Yes, through diodes
Will the AC gens be online wil the props in feather?
No
What do the AC gens provide power to?
The L/R 115VAC buses
If an AC gen failed in flight, would the opposite AC bus be powered?
Yes through the bottom bus tie
Which buses power the TRU’s?
115VAC buses
What buses are directly powered by the TRU’s?
L/R secondary buses
What is the input and output of the TRUs?
In: 3 phase (87Amp per phase) 115V VAC
Out: 28V DC, 200Amp max each, (25-29.5V dependant on load)
How can a TRU be turned off?
Pull the CB