ATA 24 - Electrical

Question 1

Description electrical system ?

Answer 1

Cf diagram

Question 2

Engine GEN and APU: kVA, Volt, Hz, phase ?

Answer 2

90kVA
115/200V
400 Hz
Tri phases

Question 3

EMER GEN: kVA, V, Hz, phase ?

Answer 3

5kVA
115/200V
400 Hz
Tri phases

Question 4

Static inverter: kVA, V, Hz, phase ?

Answer 4

1kVA
115/200V
400 Hz
Single phase

Question 5

Batteries: Ah and V ?

Answer 5

23 Ah
28 V

Question 6

Max oil temperature IDG before FAULT ? Auto cut out at which temperature ?

Answer 6

180°C = FAULT
200°C = auto cut out

Question 7

Inhibition of low pressure FAULT light on IDG at below which N2 ?

Answer 7

Below 14% N2

Question 8

Time to charge batteries 100% ?

Answer 8

20min

Question 9

Mini batterie voltage ? What does it ensure ?

Answer 9

25,5 V. It ensures 50% minimum capacity (cf SOP)

Question 10

Priority of electrical sources ?

Answer 10

GEN of same side
EXT PWR
APU
GEN opposite side

Question 11

<—[DC BAT]—>

—[DC BAT]—

> —[DC BAT]—<

meaning ?

Answer 11

DC BAT charges batteries above 1A
No charge
Batteries discharge above 1A

Question 12

GALY and CAB pb controls which system ? What is the shed logic ?

Answer 12

AUTO: sheds main galley (ovens, …), in seat power, IFE if 1 GEN only
OFF: sheds also secondary galley ( coffee maker…)

Question 13

COMMERCIAL pb controls which system ?

Answer 13

Cargo / Cabin lights
Water / Waste
Drain mast protection
IFE

Question 14

Time for RAT deployment and EMER GEN to start ?

Answer 14

8 s
Gap filled by BAT

Question 15

Conditions for auto RAT out ?

Answer 15

AC 1 + 2 out
And
Above 100 kt

Question 16

On EMER GEN conditions, batteries cannot be charged. True or False ?

Answer 16

True

Question 17

EMER GEN
When the aircraft is on ground :
- Below XXXkt, DC BAT BUS is automatically connected to the batteries.
- Below XXX kt, AC ESS BUS is automatically shed, leading to the loss of all display units.

Answer 17

100kt
50kt

Question 18

Autonomy flight on BAT only ?

Answer 18

30min

Question 19

Meaning of green breaker ?

Answer 19

ECAM monitored
After 1 min message on ECAM

Question 20

Meaning of black breaker ?

Answer 20

Not ECAM monitored
Only associated with system fault message

Question 21

Meaning of yellow breaker ?

Answer 21

May increase BAT life if tripped (old aircraft)

Question 22

Meaning of red breaker ?

Answer 22

WTB. No reset.

Question 23

How many times can you reset a breaker ?

Answer 23

1 time. Follow procedure

Question 24

CLR pb effect on breaker ?

Answer 24

Inhibits any CB tripped on same panel

Question 25

EMER CANCEL pb effect on breaker ?

Answer 25

Inhibits caution

Question 26

On ground, if only the batteries are powering the emergency generation network, APU start is only available when the speed is below XX kt ?

Answer 26

100kt

Question 27

Normal electrical distribution ? (Diagram)

Answer 27

GEN 1 — AC 1 bus — TR 1— DC 1 bus — DC BAT bus —DC ESS bus BAT 1 BAT 2 | | | | AC ESS bus DC ESS bus Hot bus 1 Hot bus 2 + Shed + Shed GEN 2 — AC 2 bus — TR 2— DC 2 bus

Question 28

When no other power is available in flight, the static inverter converts _____ power to AC power for the AC ESS bus; and ______ powers the DC ESS bus

Answer 28

BAT 1 BAT 2

Question 29

When BAT FAULT light will illuminate ?

Answer 29

Charging current increase abnormally

Question 30

Is it possible to parallel generators?

Answer 30

No

Question 31

What is the significance of the circuit breakers on the overhead panel?

Answer 31

They may be operational in the Emergency Electrical Configuration.

Question 32

If a TR 1 fails, show distribution diagram ?

Answer 32

GEN 1 — AC 1 | AC ESS + shed — TR ESS — DC ESS GEN 2 — AC 2 — TR 2 — DC 2 — DC BAT — DC 1

Question 33

In flight, in case of loss of all main generators, EMERGENCY GENERATOR not running, the STATIC INVERTER supplies which bus ?

Answer 33

AC ESS bus ( APU, ENG start…)

Question 34

What happens during the EMER GEN TEST if AC NORMAL BUSES are supplied ?

Answer 34

EMER GEN is supplied by Blue electrical pump if operating + AC ESS and DC ESS are connected to EMER GEN (If only the batteries supply the aircraft: The static inverter powers the AC ESS BUS.)

Question 35

When is the DC BAT BUS supplied by the batteries ?

Answer 35

APU starting and AC1 & 2 lost with speed< 100kt

Question 36

In emergency configuration, when is AC ESS SHED and DC ESS SHED BUS automatically shed ?

Answer 36

During RAT deployment

Question 37

Is the ESS TR used when a TR is faulty ?

Answer 37

Yes

Question 38

When GEN 1 or GEN2is selected to "OFF" position. Does GEN are still energized or de-energized ?

Answer 38

De-energized and line contactor opens