G7500 ELECTRICAL Flashcards
(105 cards)
1
Q
What is the primary source of AC power in the GL7500
A
Two engine-driven variable frequency generators (VFGs)
2
Q
What voltage does the AC power generation system provide
A
115 VAC
3
Q
How many engine-driven variable frequency generators (VFGs) are there
A
2
4
Q
What provides auxiliary AC power
A
APU generator
5
Q
What supplies emergency AC power
A
Ram Air Turbine (RAT) generator
6
Q
Where is the external AC power connection located
A
Right side of the airplane below the engine
7
Q
How many permanent magnet generators (PMGs) supply backup AC power to FBWPCs
A
2
8
Q
What do PMGs supply backup power to
A
Fly-by-wire power converters (FBWPCs)
9
Q
What does the DC power generation system consist of
A
TRUs- batteries- and FBWPCs
10
Q
How many transformer rectifier units (TRUs) are there
A
3
11
Q
What voltage do the TRUs convert AC power to
A
28 VDC
12
Q
How many batteries are in the DC power generation system
A
2
13
Q
What type of batteries are used
A
Nickel-cadmium (NiCad)
14
Q
What voltage are the batteries rated at
A
24 VDC
15
Q
What do the batteries provide power for
A
Ground engine start-up- APU starting- RAT support- uninterrupted bus power during transfers
16
Q
What do the FBWPCs supply DC power to
A
Fly-by-wire (FBW) system
17
Q
Where do the FBWPCs get backup AC power from
A
Permanent magnet generators (PMGs)
18
Q
What does the primary power distribution system use to distribute power
A
Electrical power centers (EPCs)
19
Q
How many secondary power distribution assemblies (SPDAs) are there
A
7
20
Q
What do the SPDAs distribute
A
AC and DC electrical power throughout the airplane
21
Q
What functions does the electrical system provide for all components
A
Monitoring and protection functions
22
Q
What happens when power sources are lost
A
Load shedding reduces current draw by taking non-essential loads offline
23
Q
What is the purpose of load shedding
A
To prevent remaining power sources from overloading
24
Q
What does MAIN BATT stand for
A
Main Battery
25
What does APU BATT stand for
Auxiliary Power Unit Battery
26
What does ESS TRU stand for
Essential Bus Transformer Rectifier Unit
27
What does RAT stand for
Ram Air Turbine
28
Where is the ELECTRICAL panel located
Overhead in the flight compartment
29
What controls and indications does the ELECTRICAL panel provide
MAIN BATT/APU BATT switches- BUS ISOL rotary switch- EXT AC PBA- generator (L GEN- APU GEN- R GEN) control PBAs
30
What are the MAIN BATT and APU BATT switches for
Control connection of batteries to the airplane DC electrical system
31
What is the BUS ISOL rotary switch for
Selectively isolate groups of buses in case of electrical failure or smoke
32
What is the EXT AC power pushbutton annunciator (PBA) for
Control connection of external AC power
33
What are the generator (L GEN- APU GEN- R GEN) control PBAs for
Reset generators or take them off line
34
When are the generators automatically placed on line
When the APU and airplane engines are operating
35
How are generator PBAs normally left
ON (pressed out) position
36
What happens when a PBA is pressed in to take a generator off line
White OFF light comes on in the PBA and a GEN OFF CAS message appears
37
What is the CABIN panel used for
Control cabin electrical loads and outlets
38
Where is the CABIN panel located
Overhead in the flight compartment
39
What does the POWER PBA control
Power to all cabin electrical loads
40
What does the OUTLET PBA control
Power to the cabin electrical outlets only
41
What happens when the POWER PBA is pressed
White OFF light comes on- CABIN POWER OFF CAS message appears- all cabin power removed
42
What happens when the OUTLET PBA is pressed
White OFF light comes on- power to cabin outlets removed- no CAS message
43
Where is the RAT deployment handle installed
Bottom of the center pedestal in the flight compartment
44
When does the RAT deploy automatically
Following the loss of all electrical generators in flight
45
How can the RAT be manually deployed
Lift the covered RAT deployment handle
46
Where is the BATT LOADS switch located
Passenger door switch panel
47
What does the BATT LOADS switch do
Disconnects most electrical loads from the batteries
48
What remains available after placing the BATT LOADS switch to DISC
Hot battery bus loads (passenger door- APU FADEC- APU door)
49
Where is the external ground power panel located
Lower part of the belly fairing below the right engine
50
What controls and indications are on the external ground power panel
EXT AC indicator- GROUND SERVICE mode PBA- BATTERY MASTER indicator- AC power connector- LAMP TEST button
51
What is the LAMP TEST button for
Test the external ground power panel PBA lamps
52
Where is the flight compartment CBP located
Avionics rack behind the copilot seat
53
What does the flight compartment CBP provide
Distribution and protection for 28 VDC and 115 VAC power to AC ESS BUS and DC ESS BUS loads
54
What is the main AC power source for the electrical system
Engine-driven variable frequency generators (VFGs)
55
How many AC buses does AC power route to
3
56
Which generator normally supplies AC BUS 1 and the AC essential (ESS) bus
Left generator (L GEN)
57
Which generator normally supplies AC BUS 2
Right generator (R GEN)
58
What happens in the event of a generator failure
Remaining VFG can supply all three AC buses
59
What can also power the entire AC electrical system
APU generator and/or external AC power source
60
What is load shed during single generator operations
Some high load users such as certain hydraulic system pumps
61
What is the primary DC power generation source
Transformer rectifier units (TRUs)
62
How many DC buses are there
6
63
Where is the main battery located
Forward equipment bay in the nose of the airplane
64
Where is the APU battery located
Belly fairing compartment below the baggage bay door
65
What is the battery capacity in ampere-hours
28 Ah
66
What is the limitation for APU Start at temperatures below -40°C
Limited power capacity if cold soaked for longer than 10 hours
67
What maintains the batteries fully charged
DC voltage source from DC ESS BUS 1
68
What are the MAIN BATT BUS and APU BATT BUS considered
Hot buses (continuously powered)
69
What do the MAIN BATT and APU BATT switches control
Connection of batteries to the airplane DC electrical system
70
What happens when the battery switches are OFF
DC ESS BUS 1 is isolated from MAIN and APU BATT buses
71
What happens when the battery switches are ON
Each battery is connected to DC ESS BUS 1 through its respective MAIN/APU BATT BUS
72
What does the BATT DISCHARGING CAS message indicate
Either or both batteries are discharging
73
What is the output frequency range of the engine-driven VFGs
360 to 650 Hz
74
What is the rated continuous output of each VFG
60 kVA
75
What is the maximum short-term (5 seconds) output of each VFG
90 kVA
76
What controls the connection of the VFGs to the AC electrical system
Generator control unit (GCU)
77
Where are the GCUs located
Left and right aft avionics racks in the rear section of the baggage compartment
78
How is each VFG cooled and lubricated
Independent dedicated oil circuit cooled by fuel/oil heat exchanger
79
What happens if VFG oil temperature becomes excessive or there is a seizure
VFG is mechanically disconnected from the engine accessory gearbox
80
What is the rated continuous output of the APU generator
60 kVA
81
What is the output frequency of the APU generator
400 Hz ±4 Hz
82
Where is the APU generator located
APU accessory gearbox in the tail cone
83
What is the load limit on the APU generator above 45
000 feet
84
How is the APU generator cooled and lubricated
Oil shared by the APU engine and generator
85
Can the APU generator be mechanically disconnected
No it does not have a disconnect mechanism
86
What is the rated continuous output of the RAT generator
9 kVA
87
What is the maximum short-term (5 seconds) output of the RAT generator
18 kVA
88
What is the output frequency range of the RAT generator
340 to 430 Hz
89
Where is the RAT stored
Compartment on the right side of the nose
90
What powers the AC ESS BUS when the RAT is deployed
RAT generator
91
What powers DC ESS BUS 1 when the RAT is deployed
ESS TRU
92
What powers DC ESS BUS 2 when the RAT is deployed
DC ESS BUS 1
93
What powers the MAIN BATT BUS and APU BATT BUS when the RAT is deployed
DC ESS BUS 1
94
What is the minimum speed for the ESS TRU to power DC ESS BUS 1 during RAT operation
147 kt
95
What does the EMER PWR ONLY CAS message indicate
Loss of main power generation in flight (on RAT or batteries)
96
What does the RAT GEN ON CAS message indicate
RAT is deployed and powering the AC ESS BUS
97
What is the purpose of the RAT safety pin
Prevents RAT from deploying on the ground
98
Where is the RAT safety pin located
Right wall inside the nose wheel well
99
What happens if the RAT generator trips offline
Can be reset by moving the deployment handle to stow and back to deploy
100
What is the priority order for AC BUS 1 and AC BUS 2 power sources
Onside engine VFG- APU generator- external AC power- opposite side engine VFG
101
What is the normal position of the BUS ISOL switch
AUTO
102
What does the BUS ISOL switch do in the AUTO position
AC and DC buses are normally powered- switching is automatic
103
What happens when the BUS ISOL switch is selected to the L (left channel) detent
Left channel EPCs are isolated from other EPCs
104
What happens when the BUS ISOL switch is selected to the R (right channel) detent
Right channel EPCs are isolated from other EPCs
105
What happens when the BUS ISOL switch is selected to the ESS (essential channel) detent
Essential channel EPCs are isolated from other EPCs
