Electrics Flashcards
1
Q
Fuel Panel Switches - Larger ones are ____ smaller ones are ______
A
Fuel Panel Switches - Larger ones are AC smaller ones are DC
2
Q
Power to the boost pumps is supplied from the MAIN AC BUS ___ for Pump ___ and ____ and from the MAIN AC BUS ___ for Pump ____ and ____.
A
Power to the boost pumps is supplied from the MAIN AC BUS A for Pump No.1 and No.3 and from the MAIN AC BUS B for Pump No.2 and No.4
3
Q
Function of External power monitor relay:
A
Prevents power with improper phase, voltage or frequency to power the AC
4
Q
Power source to MAIN AC BUS A and B are assured by:
A
Transfer Relay system
5
Q
If you lose MON DC, you lose START DC…. to regain START DC, what can you do?
A
Select any engine on the starter or the emergency inverter.
6
Q
If the Run around relay circuitry fails, the FLT ESS AC bus is powered by what:
A
Main AC BUS A
7
Q
During APU GEN Only the following is automatically de-energized above 8K’
A
a. No.1A Hydraulic pump.
b. Empennage de-ice system.
c. Circuit de-energized by the load monitor control relay
8
Q
When the yellow GEN light is illuminated on the horizontal panel
A
Indicates a primary gen drive bearing failure, aux bearing in use
9
Q
The nose gear up and locked switch when up and lock will disable:
A
GOB and cabin warning horn.
10
Q
If you lose main AC BUS B you lose which boost pumps and which hyd pumps
A
Boost pumps 2-4
1A and 2 hyd pumps
11
Q
GEN 4 off light:
A
Indicates that the GEN is unable to power any bus
12
Q
STBY ATT Indicator is powered by:
A
Flight ESS DC
13
Q
If APU gen is the only one, how is the flt ess AC bus powered:
A
APU GEN trhough RAR relays.
14
Q
What activates load shedding:
A
selecting prop or emp de-ice
15
Q
Gen 4 and APU are the only available gens, which provides power
A
Gen 4 is the only power
16
Q
TRUs are de-energized by
A
Pulling the CB
17
Q
If Main AC A fails, MON AC bus is powered by any gen through_______
A
RAR relays
18
Q
The Supp panel does not provide:
A
Overfrequency protection
19
Q
Battery V & AmpH
A
24 volts, 31 amph
20
Q
Gen 3 off light illuminates means:
A
Not powering bus B
21
Q
The emergency inverter powers: what
A
TIT indicators (START ESS AC)
22
Q
Purpose of load monitor circuit
A
Prevent exceeding load capacity of a single gen in flight
23
Q
Ground air sensing circuit disables:
A
Jettison circuit on the ground
24
Q
If TR1 and TR3 fails
A
Lose noting (1 and 2 à loose main and ext main DC)
25
Total of __ generators. Only __ Generators can power the AC Buses at anyone time. When Gen __ and __ are operating, Gen __ and ___ Gen are in Standby Mode.
Total of 4 generators. Only 2 Generators can power the AC Buses at anyone time. When Gen 2 and 3 are operating, Gen 4 and APU Gen are in Standby Mode.
26
Gen __ and ___ Gen cannot power the AC buses simultaneously, but rather __________
Gen 4 and APU Gen cannot power the AC buses simultaneously, but rather Only one at a time
27
There are __ AC buses. What are they called?
5 AC buses:
Flight Essential AC Bus
Main AC Bus A
Main AC Bus B
Mon Essential AC Bus
Start Essential AC Bus
28
There are __ DC buses. What are they called
7 DC Buses
Flight Essential DC Bus
Main DC Bus
Ext Main DC Bus
Mon Essential DC Bus
Start Essential DC Bus
APU Essential DC Bus
Ground Operation Bus (GOB) DC BUS
29
The most critical of the AC buses for flight would be the_________________
FLIGHT ESS AC BUS.
30
There are __ TRUs which convert ___ VAC to __ VDC.
There are 3 TRUs which convert 120 VAC to 28 VDC.
31
TRU 1 and 2 both power ______________ BUS.
TRU 1 and 2 both power MAIN DC BUS.
32
TRU 3 powers ______________ BUS.
TRU 3 powers MON ESS DC BUS.
33
Transformer rectifiers, convert ____ to _____
Transformer rectifiers, convert 120 VAC to 28 VDC
34
The voltage regulator section is designed to provide excitation to a generator and to maintain a pre-set voltage level of ______ VAC under all load conditions when the generator is on line (NORMAL RPM).
The voltage regulator section is designed to provide excitation to a generator and to maintain a pre-set voltage level of 117 (±2) VAC under all load conditions when the generator is on line (NORMAL RPM).
35
_____________ Powers TRU No.1 which supplies power to ______________BUS.
MAIN AC BUS A Powers TRU No.1 which supplies power to MAIN DC BUS.
36
________________ powers TRU No.2 which supplies power to the ___________________
MAIN AC BUS B powers TRU No.2 which supplies power to the MAIN DC BUS
37
________________ powers TRU No.3 which supplies power to the __________________
MON ESS AC BUS powers TRU No.3 which supplies power to the MON ESS DC BUS
38
List 4 things that the battery powers
FLT ESS DC BUS
GOB and APU ESS DC BUS when the nose gear is down and the APU in-flight arming switch is off
START ESS DC via Inverter Relay
START ESS AC through the Emergency Inverter
39
How is the battery Charged?
by the TRUs through the FLT ESS DC BUS and blocking diode # 2
40
Generator output is regulated at:
120 V (117 +/-2)
41
Where are the Flight Essential AC and the Flight Essential DC Buses located.
Forward electrical load centre
42
What actions must be taken if Engine 2, 3, or 4 RPM exceeds 109 % ?
THE RESPECTIVE GENERATOR SWITCH MUST BE SELECTED OFF
43
Name the 2 Main AC Buses ?
MAIN AC BUS A
MAIN AC BUS B
44
If battery power is not available, external power can be used. True or False ?
FALSE
45
The APU generator can supply power to operate:
Entire electrical system on the ground when external electrical power is not available
46
What is the function of the Transformer Rectifiers ?
CONVERT AC POWER TO DC POWER
47
What protection is not provided by the voltage regulator / supervisory panel
Overfrequency
48
What does the “GEN” light on the horizontal annunciator panel indicate ?
THE GENERATOR IS BEING SUPPORTED BY THE AUX BEARING
49
What is the purpose of the EMP DE-ICE MONITOR switch ?
TO ALLOW THE USE OF EMP DE-ICE DURING SINGLE GENERATOR (APU) OPS ABOVE 8000’
50
What is the purpose of the EXTERNAL POWER MONITOR RELAY ?
ENSURES PROPER PHASE, VOLTAGE AND FREQUENCY IS AVAILABLE TO THE A/C
51
What is the function of the EMERGENCY INVERTER ?
CONVERT DC POWER TO AC POWER TO POWER START ESS AC
52
What is the purpose of the BUS MONITORING SWITCHES?
ALLOWS THE RESPECTIVE BUS TO TO BE ISOLATED FROM ANY POWER SOURCE (Normally ‘ON’)
53
What is indicated by the GEN 4 “OFF” light illuminated ?
GEN 4 IS NOT CAPABLE OF POWERING ANY BUS
54
The minimum voltage limits of the battery with the inverter test switch selected are:
Aircraft buses off : 22 volts, T.R. powered : 25 to 30 volts
55
Main AC Bus A normally powered by Gen 2 - 4, APU , 3 backup
Main AC Bus A normally powered by Gen 2 - 4, APU , 3 backup
56
Main AC Bus B normally powered by Gen 3 - 4, APU, 2 backup
Main AC Bus B normally powered by Gen 3 - 4, APU, 2 backup
57
What is the normal power source for the Main DC Bus?
MAIN AC BUS A AND MAIN AC BUS B THROUGH TRANSFER RECTIFIERS NO. 1 AND NO. 2
58
Extension Main DC Bus is powered by ______________
Extension Main DC Bus is powered by Main DC BUS
59
Mon essential AC bus is normally powered by MAIN AC Bus A. If Bus A fails, Mon Ess AC bus can be powered by any available generator via the runaround relays with what priorities ?
gen light
60
Engine Instrument Power Sources
Monkey Mon Ess AC
Shit Start essential AC
Tastes Tach Gen (AC)
Awful Bus A (AC)
61
Oil indicator Power Sources
E Ext Main DC
I Inst. Bus (AC) 1 2 2 1
E Ext Main DC
I Inst Bus (AC) 1 2 2 1
I Inst Bus (AC) 1 2 2 1
62
Power source: If it’s delicate/breakable (Screen or something) / Small Switch = ____
Power source: If it’s delicate/breakable (Screen or something) / Small Switch = DC
63
Power Source: If it’s big, or think it drains a lot of power / Big Switch = ____
Power Source: If it’s big, or think it drains a lot of power / Big Switch = AC
64
Transfer Relays allow ________________________ to power the Main ____ Buses.
Transfer Relays allow any operating generator to power the Main AC Buses.
65
With only one engine driven generator operating above 8000 feet, when will the electrical system load monitor ?
WHEN PROP DE-ICE OR EMP DE-ICE IS SELECTED ON
66
When operating with APU generator only above 8000 feet, what additional items are load monitored?
NO. 1A HYDRAULIC PUMP AND EMP DE-ICE
67
When operating with APU generator only (single generator) above 8000 feet , you need to use:
emp de-ice
68
Prior to selecting emp de-ice monitor switch to override, you need to reduce an equivalent load. Equivalent loads consist of what?
No.1 hyd pump (boost out)
3 Fuel Boost pumps
Cabin exhaust fan
69
Runaround Relays allow any operating generator to power what buses?
THE ESSENTIAL BUSES
70
While in flight or on the ground, can you enter the MELC with power on the Aircraft?
NEGATIVE
71
What is/are the last Bus/Buses to lose power?
FLIGHT ESS AC AND FLIGHT ESS DC BUSES
72
Where do the engine driven generators get cooling air ?
ENGINE OIL COOLER INTAKE
73
Where is Transformer Rectifier 3 located ?
FELC
74
What action is required if a TR overheat light illuminates ?
CONSULT THE AOI’s; PULL RESPECTIVE CB OUT
75
What is the maximum airspeed and altitude for APU operation in flight ?
225 KTS & 20000 FEET
76
What if you are APU single gen ops above 8000’, and you need to use the emp-de/ice ?
225 KTS
18,200’ ICAO Std day
(16,000 Mil-std hot day)
77
Gen 2 OFF light indicates :
Gen # 2 is not powering Main AC Bus A
78
The Voltage Regulation/Supervisory Panel performs the following functions: (x4)
1. Voltage regulation & bus transfer control
2. Under frequency protection (auto reset)
3. Over voltage and under voltage protection (manual reset)
4. Feeder fault protection (not resettable)
79
Where are the Voltage regulation/Supervisory Panlels Located?
In the MELC
80
when RPM exceeds ______ Over frequency protection is NOT provided, and the generator must be turned off.
109%
81
TRUs supply ___ VDC at a rate of ____ amps each
TRUs supply 28 VDC at a rate of 200 amps each
82
why is it that the illumination of the Ext Pwr Available light does not assure availability of AC power to the aircraft? (x4)
a. Nose gear uplock not properly positioned.
b. Battery not connected.
c. Gen #4 Run Around Relay feeder CB out.
d. Ext Pwr CB out
83
True or False? A NEON External Pwr Available Light will only illuminate when external power is available to the aircraft?
False -a NEON External Pwr Available Light will illuminate simply when a cable is connected to the aircraft (regardless of whether or not power is actually available. A GREEN on light will illuminate when power is applied to the ACFT buses.
84
Components on Flight Essential AC Bus (x4)
P Pitot Heat (Pilot)
I IFF Lobbing Switch
O Outflow Valve
I Instrument Panel Light
85
Components on Flight Essential DC Bus (x10)
P Pitchlock Reset
I Inverter Relay
T Transponder
S Stby Attitude Indicator
B Bell (Command Bell)
U Utility Light
R (FDR/CVR)
G GOB
A Air Data Computer
V VHF/AM
86
Mission related Components typically on= __________________
Mission related Components typically on= Main AC Bus A
87
Icing Components typically on= _______________________
Icing Components typically on= Main AC Bus B
88
Bulk of Electrical Supply to non-critical equipment are on what buses?
The Mains:
Main AC BUS A
Main AC Bus B
Main DC Bus
Ext Main DC Bus
89
GEN 2,3 or 4(Horizontal AP) Light
Primary front bearing has failed. Secondary bearing is smaller thus a contact is made giving light. If accompanied by Uncorrectable GEN malfunction ESD (note unless a greater emerg does not apply). Good for 10 hrs with no Uncorrectable GEN malfunction.
90
Mon ESS DC powers the ESS DC feeders 1, 2, 3, (SAM). Sam means: (x3)
S Start DC (feeder 3)
A armament bus (feeder 1)
M Mon essential DC bus (feeder 2)
91
___ lies and ___ Dies = If it is powered by AC it will give a false indication, if it is powered by DC is it will just read Zero.
AC lies and DC Dies = If it is powered by AC it will give a false indication, if it is powered by DC is it will just read Zero.
92
AC power supply
gen 2-4+ APU
93
How are the gens cooled
oil cooler duct through mechanically operated valve
94
Rating of the Generator
60KVA on the ground 980KVA Airborne, temporary peak of 120 V
95
What is the purpose of the inverter battery test switch?
Run the inverter and power the start ess ac and check the battery voltage under load
96
What is the purpose of the Transfer relay?
they allow any generator to power MAIN AC BUS A and MAIN AC BUS B
97
What is the function of GEN 4 AUX Control Relay
Controls operation of Transfer relays 5 & 6
98
What prevents the FLT ESS DC BUS from powering the MON ESS DC BUC?
Blocking Diode #2
99
What three components can be used to power the GOB airborne?
1.Put the gear down, 2.Arm the APU Arming Switch, 3. Pull GOB CB
100
How can the START ESS DC BUS be alternately powered?
by the – Flight Essential DC BUS – inverter battery switch to test, select any engine, and pull the power sensing CB
101
What function does transfer relay #7 provide
Provides priority to Gen 4 over the APU?
102
What normally powers the MON ESS AC BUS?
MAIN AC BUS A
103
What normally powers the FLT ESS AC BUS and what is the priority?
GEN 2, 4, APU, 3, BUS A
104
What is the START ESS DC BUS used to power?
TIT Indicators
105
What powers the FWD LTG bus
MON ESS AC BUS
106
What normally powers the STRT ESS DC BUS
MON ESS DC BUS through feeders
107
What is the primary power source for the FLT ESS DC BUS (ACFT Powered)
MON ESS DC BUS through blocking diode 2
108
How many scissor switches are there and where are they?
2, one on each main gear
109
Which two systems are directly controlled by scissor switches
flight idle stop and jettison circuit
110
What buses can be powered by the battery with no ground power applied
Start ess ac through emerg inverter
Start ess DC
GOB
APU Ess DC
Flight Ess DC
