Electrical Systems Flashcards
batteries volts and amps
2, 24 volt and 28 amps
how long do the batteries guarantee power for (if operated correctly)
30 minutes
generator volt and amps
28V, 300 amps
battery amp charge rate must be less than ____ prior to takeoff
20 amps
AC power voltage
115 volts, 400 Hz power
transient load of 400 amps is allowed for
2 minutes max
can tripped circuit breakers be reset
no unless deemed necessary, only 1 attempt is allowed
Bus with a P
DC
Bus with an X
AC
Bus with S
split
6 positions on the rotary switch
B1, B2, PS1, PS2, PE, XFER
____ V or greater will cause GCU to open GLC due to over voltage
32.5
How many generators?
3
each engine, APU
bus tie contractor will automatically open if the system drops below
24.5 V
must be under _____ amps for takeoff
20
Where does the Gpu plug in
right, aft fuselage (close to under the tail, by the apu exhaust)
what do inverters do
convert DC to AC power
only power source that will every DC bus
gpu
Red circuit breaker
fire supression
white circuit breaker
unswitched PE
yellow circuit breaker
electric pitch trim
gpu stabilize bus bars at
28.5V
what N2 turns starter to generator
42%
Max continuous generator load
300 amps
over is 400 amps
starter limits
30 sec on, 1 min off
30 sec on, 1 min off
30 sec on, 30 minutes off
Volt regulator will open GLC if
reverse current
overexcitation
overvoltage 32.5 volts
bus-tie contractor will open if
29.5 +/- .5 V
24.5 +/- .5 V
When a generator is offline and the GEN Fail and ELECT annunciators are illuminated, the generator can be reinstated by:
Positioning the GEN switch to CLOSE for five seconds, then releasing it.
The battery charging rate can be monitored by
depressing the BATT ammeter pushbuttom
GPU must produce: for engine starting
28 volts, 1500 amps, 1100 amp current limiter
APU is connected to which bus
PS2 Bus
What can power the PS1 bus
generator or ground power
how many volts does the APU have and what does it run
28, PS2
what gives power to PS1
PS2 but only when bus tie connector is tied which is done manually
PS1 and PS2 run what
charge battery 1 and 2 (24 volts each)
PE bus (28 volts)
what bus runs even in full electrical failure
PE
what turns the generator from starter to generator
GPU
what does the GCU do
voltage regulator
protects from reverse flow
stabilizes bus bars at 28.5
protects over voltage at 32.5 volts
what circuit breakers get pulled to reserve power
all the white ones
how do you charge batteries with GPU
ext battery CGH ON switch
if checking the power of a bus and it is left on, what will happen
battery will be dead
