4 - Electrics

Question 1

1. (DSC-24-10) In normal electrical configuration, how is DC ESS bus supplied;

(a) From TR 1 via DC bus 1 and DC Bat Bus
(b) From ESS TR.
(c) From TR 2.
(d) From Batt 2.

Answer 1

(a) From TR 1 via DC bus 1 and DC Bat Bus

Question 2

2. (DSC-24-10) What happens in case of total loss of main generators;

(a) The Rat is automatically extended and powers the yellow system which drives the emergency generator.

(b) The Rat is automatically extended and powers the blue system which drives the emergency generator.

(c) The Rat has to be manually extended.

(d) The Rat is extended and mechanically connected to the emergency generator.

Answer 2

(b) The Rat is automatically extended and powers the blue system which drives the emergency generator.

Question 3

3. (DSC-24-10) the electrical power system consists of

(a) A three phase 115/200 volt 400 hertz constant frequency AC system and a 28 DC system

(b) A three phase 180/220 volt 400 hertz constant frequency system and a 28 volt DC system

(c) A three phase 115/220 volt 400 hertz constant frequency system and a 28 volt DC system
(d) A three phase 115/200 volt 400 hertz constant frequency DC system and a 28 volt AC system

Answer 3

(a) A three phase 115/200 volt 400 hertz constant frequency AC system and a 28 DC system

Question 4

4. (DSC-24-10) Dc Bat bus can be supplied by;

(a) DC Bus 1 or batteries.
(b) DC Bus 1, DC Bus 2 or batteries.
(c) DC Bus 2 or batteries.
(d) DC Bus 1 only.

Answer 4

(b) DC Bus 1, DC Bus 2 or batteries.

Question 5

5. (DSC-24-20/30) AC Bus tie contactors enable the electrical system;

(a) To be connected in parallel.
(b) To be supplied by any generator or external power.
(c) To be supplied by apu gen or external power only
(d) To be tied to external dc power.

Answer 5

(b) To be supplied by any generator or external power.

Question 6

6. (DSC-24-20/30) What happens during the emergency gen. test;

(a) The ram air turbine is extended.

(b) The blue system is pressurised and the emergency generator comes on line.

(c) The green system is pressurised and the emergency generator comes on line, supplied by hot bus 2.

(d) The emergency generator comes on line and the yellow system is pressurised.

Answer 6

(b) The blue system is pressurised and the emergency generator comes on line.

Question 7

7. (PRO-NOR-SOP-04) Normal minimum battery voltage before apu start is ;

(a) 22v.
(b) 25.5v.
(c) 27.5v.
(d) No Minimum.

Answer 7

(b) 25.5v.

Question 8

8. (DSC-24-20/30) When disconnecting the IDG the button should be pressed;

(a) For no more than 3 secs.
(b) For longer than 3 secs.
(c) Until the fault light goes out.
(d) For no more than 5secs.

Answer 8

(a) For no more than 3 secs.

Question 9

9. (DSC-24-20/30) On the emergency electrical power panel, a fault light illuminates under the ‘ RAT and Emer.Gen.’ label. What does it mean ;

(a) Rat is not extended.

(b) Emergency generator is not supplying when AC bus 1 and 2 are not powered or Dc Bat bus is not powered.

(c) Emergency generator is supplying but AC Ess bus is not powered.

(d) Emergency generator is not supplying when AC Bus 1 and 2 are not powered.

Answer 9

(d) Emergency generator is not supplying when AC Bus 1 and 2 are not powered

Question 10

10. (DSC-24-20/30) What happens when the Gen 1 line Pb. is set to off;

(a) AC Bus one and 2 are not powered and emergency generator is automatically connected.

(b) AC Bus 1 is powered by the gen. 2 because the gen 1 is deactivated.

(c) AC Bus 1 is powered by the gen.2 because the gen.1 line contactor is opened.

(d) AC Bus 1 is not powered because the gen. 1 line contactor is opened and transfer contactor is not closed.

Answer 10

(c) AC Bus 1 is powered by the gen.2 because the gen.1 line contactor is opened.

Question 11

11 (DSC-24-20/30) Where can the battery voltage be checked;

(a) On the ECAM elec page only
(b) On the elec overhead panel and the ECAM elec page
(c) On the elec overhead panel and the ECAM E/WD
(d) On the elec overhead panel only

Answer 11

(b) On the elec overhead panel and the ECAM elec page

Question 12

12. (DSC-24-10) AC essential bus is normally supplied by;

(a) AC Bus 1.
(b) AC Bus 2.
(c) Static inverter.
(d) Emer. gen.

Answer 12

(a) AC Bus 1.

Question 13

13. (DSC-24-10) In flight on batteries only, the AC Ess Shed bus and DC Ess Shed bus are lost;

(a) Yes.
(b) No.
(c) Only A/C Ess Shed Bus is lost.
(d) Only D/C Ess Shed Bus is lost.

Answer 13

(a) Yes.

Question 14

14. (DSC-24-10)The static inverter works;

(a) Always.
(b) When A/C speed is > 50kts and on batteries only.
(c) When one main generator fails.
(d) Only when gen. 2 fails.

Answer 14

(b) When A/C speed is > 50kts and on batteries only.

Question 15

15. (DSC-24-20/30) On ground what happens if the RAT and Emer. Gen. Man On Pb. Is pressed

(a) The Rat is extended.
(b) The emergency generator is activated.
(c) Nothing.
(d) The blue hydraulic system is pressurised and this causes the RAT to extend and rotate.

Answer 15

(a) The Rat is extended.

Question 16

16. (DSC-24-10)The static inverter transforms the DC voltage from the battery bus into;

(a) Single phase 115v - 400 Hz. A/C current.
(b) Three phase 115/200v - 400hz. A/C current.
(c) 28v D/C current.
(d) 25.5v D/C current.

Answer 16

(a) Single phase 115v - 400 Hz. A/C current.

Question 17

17. (DSC-24-10) In flight in case of loss of all main generators, emergency generator not yet running (batteries only), the static inverter supplies ;

(a) A/C Ess bus and Engine Ignition A
(b) Eng Ignition & A/C Ess Bus & A/C Ess Shed Bus
(c) Eng Ignition Only.
(d) Hot bus 1.

Answer 17

(a) A/C Ess bus and Engine Ignition A

Question 18

18. (DSC-24-20/30) The external power has priority over the Apu. gen.;

(a) Yes.
(b) No.
(c) Only in flight.
(d) No, Apu. gen. has priority over external power always.

Answer 18

(a) Yes.

Question 19

19. (DSC-24-10) Gen 1 and Gen 2 when operating have priority over the Apu gen;
    (a) Yes.
    (b) No.
    (c) Only in flight.
    (d) Only on the ground.

Answer 19

(a) Yes

Question 20

20. (DSC-24-10) With Apu gen. available, if one main generator fails, the failed generator is replaced by;

(a) The Apu.
(b) The other computer.
(c) Bus tie takes place and the remaining main generator supplies both channels.
(d) The RAT.

Answer 20

(a) The Apu.

Question 21

21. (DSC-24-10) If a TR fails;

(a) The other TR automatically replaces the faulty one & the Ess TR supplies the DC Ess Bus.

(b) The Static inverter replaces the faulty TR.

(c) The DC Bus on the faulty side is lost.

(d) The Emergency generator supplies DC power on the faulty side.

Answer 21

(a) The other TR automatically replaces the faulty one & the Ess TR supplies the DC Ess Bus.

Question 22

22. (DSC-24-10) In flight in case of loss of all main generators, emergency generator not running, the DC Ess Bus is supplied by;

(a) Hot bus 2.
(b) Ess TR.
(c) Both.
(d) Hot Bus 1.

Answer 22

(a) Hot bus 2.

Question 23

23. (DSC-24-10) In flight in case of loss of all main generators, emergency generator running , the DC Ess Bus is supplied by the;

(a) Hot bus.
(b) Ess TR.
(c) Both.
(d) DC Bat bus.

Answer 23

(b) Ess TR.

Question 24

24. (DSC-24-10) The IDG regulates the …….. of the generator;

(a) Speed.
(b) Voltage.
(c) Frequency.
(d) GLC (generator line contactor)

Answer 24

(a) Speed.

Question 25

25. (DSC-24-20/30) When switched to ALTN the AC Ess Feed p/b causes the AC Ess Bus to be; (a) Supplied from AC bus 1 (b) Supplied from AC bus 2 (c) Supplied from DC bus 1 (d) Supplied from DC bus 2

Answer 25

(b) Supplied from AC bus 2

Question 26

26. (DSC-24-10) If AC bus 1 fails the AC Ess bus is supplied by; (a) Emer Gen. (b) AC Bus 2. (c) Static inverter. (d) The RAT.

Answer 26

(b) AC Bus 2.

Question 27

27. (DSC-24-10) In case of total electrical loss the AC Ess bus is supplied by; (a) Static inverter. (b) Emer Gen. (c) Both. (d) TR 1.

Answer 27

(a) Static inverter.

Question 28

28. (DSC-24-10) In Emergency configuration, AC Ess shed bus is automatically shed; (a) If the RAT stalls or aircraft is on ground with speed<100kts (b) When the landing gear is down. (c) When in emergency configuration (d) When AC Bus 1 is lost

Answer 28

(a) If the RAT stalls or aircraft is on ground with speed<100kts

Question 29

29. (DSC-24-10) If one main generator fails in flight (and the APU generator is not being used) (a) Part of the galley load is automatically shed (b) All galley load is automatically shed once the APU generator becomes available. (c) All galleys are shed. (d) Galleys are not shed.

Answer 29

(a) Part of the galley load is automatically shed

Question 30

30. (DSC-24-20/30) Can you reconnect the IDG in flight; (a) Yes. (b) No. (c) No. 1 idg only. (d) No. 2 idg only.

Answer 30

(b) No.

Question 31

31. (DSC-24-20/30) When Gen. 1 or Gen. 2 is selected to off; (a) The Generator field is de-energised and the line contactor is open. (b) The Generator is still energised and line contactor is open. (c) Cannot select off in flight. (d) Can only be reset on ground.

Answer 31

(a) The Generator field is de-energised and the line contactor is open.

Question 32

32. (DSC-24-20/30) When the EXT Pwr Pb green avail is illuminated; (a) The external power is connected to the a/c. (b) The A/C network is supplied. (c) Ground services are supplied. (d) D/C network supplied.

Answer 32

(a) The external power is connected to the a/c.

Question 33

33. (DSC-24-10) Emergency generation, the D/C bat bus is automatically connected to the batteries: (a) below ‘s’ speed (b) below green dot speed (c) below 50kts (d) below 100 kts

Answer 33

(d) below 100 kts

Question 34

34. (PRO-NOR-SOP-04) When you want to check battery voltage, you must set the Bat Pb to: (a) Auto position. (b) Off position. (c) Norm position. (d) On position.

Answer 34

(b) Off position.

Question 35

35. (DSC-24-20/30) The Bat fault light illuminates when; (a) Battery voltage < 25v. (b) Battery Pb switch is at off in flight. (c) Charging current increases at an abnormal rate. (d) Charging current is low.

Answer 35

(c) Charging current increases at an abnormal rate.

Question 36

36. (DSC-24-10) In certain cases the static inverter is supplied by; (a) Hot bus 1 and Hot bus 2. (b) Hot bus 1. (c) D/C Bat bus. (d) A/C Ess bus.

Answer 36

(b) Hot bus 1.