Electrical Flashcards
What does the DC voltmeter indicate?
Voltage on the battery charging bus if the EMER BUS-NORMAL switch is in the NORMAL position.
When a GPU is used for engine start, the output should be what value?
Regulated to 28 volts and limited to 1500 amps maximum.
Which buses can the aircraft batteries power?
All buses except the 115vAC
Indication of a generator failure?
GEN switch on, GEN light illuminated and the electrical power monitor indicates no load after completing GEN fail checklist.
If aircraft electrical power fails, which systems are powered by the emergency batteries?
Standby attitude indicator and N1 indicators; instrument lights for N1 indicators, mag compass, standby attitude gyro, standby AS and standby altimeter; landing gear indicators; ADC 1 and 2 and AHS backup power.
What does illumination of the amber CUR LIM light indicate?
One or both 275-amp current limiters and blown.
What would failure of the left inverter initially result in?
Loss of power to the left AC bus.
Illumination of a red light on the electric power monitor and flashing of the left VAC display.
Illumination of the amber ELEC PWR light on the annunciator panel
Which of the following is true if both 275-amp current limiters fail in flight?
Only aircraft batteries power the L and R DC 4 buses.
Only aircraft batteries power the CAB PWR bus.
The battery-charging bus can only be powered by the aircraft batteries.
What does illumination of the red light on the electric power monitor and flashing of associated VAC display mean?
Inverter output is less than 90 VAC or above 135 VAC on the associated inverter.
or
The associated AC circuit breaker may be open.
What does illumination of the amber light on the electric power monitor and flashing of the associated amp display indicate?
Amperage draw on the associated generator is between 326-400 amps.
With aircraft generators failed and the EMER-BUS-NORMAL switch placed to the EMER BUS position, which of the following statements is true?
The aircraft batteries will power the battery buses, DC emergency, DC voltmeter, AUX HYD pump, STBY PITOT HT and PRI PITCH TRIM
What does as illuminated amber light and an increasing VDC display in the electric power monitor (EPM) indicate?
One or both of the generators is overvolting.
When illuminated, the EMR PWR light indicates?
The emergency battery switches are turned ON and the emergency batteries are not receiving a trickle charge from the aircraft electrical system.
Which of the following circuits are powered directly from battery buses?
Tailcone inspection light and toilet service receptacle, cabin entry lights, single point pressure refueling and the aft cabin and tailcone baggage compartment lights.
With dual generator failure in flight, how long should fully charged aircraft batteries last with EMER BUS-NORMAL switch in the EMER BUS position?
At least 1 hour
