BOMBARDIER CHALLENGER 604 Setup guide

Table of Contents
For Training Purposes Only
May 03 7-i
ELECTRICAL
PILOT TRAINING GUIDE
Introduction.........................................................................................................................7-1
Alternating Current (AC) System ........................................................................................7-3
Description....................................................................................................................7-3
Components and Operation..........................................................................................7-4
Integrated Drive Generators (IDGs)........................................................................7-4
APU Generator........................................................................................................7-6
External AC Electrical Power........................................................................................7-8
Description....................................................................................................................7-8
Operation ......................................................................................................................7-8
AC Electrical Power Distribution.......................................................................................7-10
Description..................................................................................................................7-10
Components and Operation........................................................................................7-11
AC BUS 1 and AC BUS 2 .....................................................................................7-11
AC ESS (Essential) Bus........................................................................................7-13
AC Utility Buses ....................................................................................................7-14
Air-Driven Generator (ADG)..............................................................................................7-15
Description..................................................................................................................7-15
Components and Operation........................................................................................7-16
Air-Driven Generator.............................................................................................7-16
ADG Auto Deploy Control Unit..............................................................................7-17
ADG Manual Deploy Handle.................................................................................7-18
DC Electrical Power System.............................................................................................7-20
Description..................................................................................................................7-20
Components and Operation........................................................................................7-22
Transformer-Rectifier Units (TRUs) ......................................................................7-22
TRU Power Distribution System............................................................................7-22
Battery Power Distribution System........................................................................7-24
External DC Electrical Power................................................................................7-25
Circuit Breakers...........................................................................................................7-27
Description............................................................................................................7-27
Controls and Indicators.....................................................................................................7-30
AC Electrical Power ....................................................................................................7-30
Air-Driven Generator (ADG)........................................................................................7-31
DC Electrical Power....................................................................................................7-32
Circuit Breaker Panels ................................................................................................7-33
EICAS Synoptic Pages ...............................................................................................7-37
AC Synoptic Page.................................................................................................7-37
DC Synoptic Page.................................................................................................7-44
EICAS Messages........................................................................................................7-50

7-ii For Training Purposes Only
May 03
ELECTRICAL PILOT TRAINING GUIDE
Page Intentionally Left Blank

List of Figures
Graphic Title Figure
For Training Purposes Only
May 03 7-iii
ELECTRICAL
PILOT TRAINING GUIDE
AC Electrical Power Sources..............................................................................................7-1
DC Electrical Power Sources..............................................................................................7-2
AC Electrical System ..........................................................................................................7-3
GEN 1 and GEN 2 Power...................................................................................................7-4
APU Power .........................................................................................................................7-5
External AC Receptacle......................................................................................................7-6
External AC Electrical Power..............................................................................................7-7
EICAS AC Electrical Synoptic Page ...................................................................................7-8
AC BUS Automatic Transfer...............................................................................................7-9
AC Essential Bus on Alternate Source .............................................................................7-10
AC Utility Bus Shedding....................................................................................................7-11
Air-Driven Generator (Wet ADG Shown)..........................................................................7-12
ADG Manual Deploy Handle and ADG Auto Deploy Control Panel..................................7-13
ADG Operation .................................................................................................................7-14
DC System Schematic......................................................................................................7-15
EICAS DC Electrical Synoptic Page.................................................................................7-16
TRU 1 Failed and MAIN BUS TIE Closed.........................................................................7-17
External DC Receptacle....................................................................................................7-18
External DC Power Connected.........................................................................................7-19
Circuit Breaker Panels (CBPs)..........................................................................................7-20
Circuit Breaker Grid System .............................................................................................7-21
ELECTRICAL POWER Panel...........................................................................................7-22
Air-Driven Generator (ADG)..............................................................................................7-23
ELECTRICAL POWER Panel...........................................................................................7-24
Circuit Breaker Panel 1.....................................................................................................7-25
Circuit Breaker Panel 2.....................................................................................................7-26
Circuit Breaker Panels 3 & 4.............................................................................................7-27
Circuit Breaker Panel 5.....................................................................................................7-28
AC Synoptic Page Color Coding - Integrated Drive Generators (1 of 2)...........................7-29
AC Synoptic Page Color Coding - Integrated Drive Generators (2 of 2)...........................7-30
AC Synoptic Page Color Coding - APU Generator (1 of 2)...............................................7-31
AC Synoptic Page Color Coding - APU Generator (2 of 2)...............................................7-32
AC Synoptic Page Color Coding - AC Electrical Power Distribution.................................7-33
AC Synoptic Page Color Coding - External AC Electrical Power......................................7-34

ELECTRICAL
7-iv For Training Purposes Only
May 03
PILOT TRAINING GUIDE
AC Synoptic Page Color Coding - Air-Driven Generator ..................................................7-35
DC Synoptic Page - TRU Power Distribution System (1 of 2) ..........................................7-36
DC Synoptic Page - TRU Power Distribution System (2 of 2) ..........................................7-37
DC Synoptic Page - Battery Power Distribution System (1 of 2) ......................................7-38
DC Synoptic Page - Battery Power Distribution System (2 of 2) ......................................7-39
DC Synoptic Page - DC Electrical Power Distribution (1 of 2)..........................................7-40
DC Synoptic Page - DC Electrical Power Distribution (2 of 2)..........................................7-41

ELECTRICAL
For Training Purposes Only
May 03 7-1
PILOT TRAINING GUIDE
CHAPTER 7: ELECTRICAL
Introduction
The Challenger 604 primarily uses 115-volt AC power and also 28-volt DC electrical
power.
Engine-driven integrated drive generators (IDGs) supply the primary source of AC
electrical power. A generator mounted on the Auxiliary Power Unit (APU) provides an
alternate source of AC electrical power. In flight, if a total loss of AC power occurs,
the air-driven generator (ADG) is deployed from the right side of the forward fuselage
to provide an emergency source of AC electrical power. External AC electrical power
is supplied through an electrical power receptacle located on the right side of the
forward fuselage.
Various aircraft systems and components require DC electrical power for operation.
DC electrical power needs are primarily supplied by four Transformer Rectifier Units
(TRU) mounted in the nose compartment. Two nickel-cadmium (NiCad) batteries,
located in the aft equipment bay, store and provide a source of DC electrical power for
normal and emergency operations.
The aircraft is capable of accepting 28-volt DC external electrical power through a DC
power receptacle installed on the rear fuselage below the right engine.
Five circuit breaker panels provide power distribution. Four circuit breaker panels are
located in the flight compartment and the fifth panel is in the aft equipment bay.
Control and operation are accomplished through the ELECTRICAL POWER Panel
located on the left side of the overhead panel. AC and DC electrical system
information is provided on the EICAS.

ELECTRICAL
7-2 For Training Purposes Only
May 03
PILOT TRAINING GUIDE
AC Electrical Power Sources
Figure 7-1
DC Electrical Power Sources
Figure 7-2
Generator 2
P604_07_001
APU
Generator
Generator 1
Air-Driven
Generator (ADG)
External
Power
Transformer
Rectifier Units
Main Battery
Charger
APU Battery
Main Battery
APU Battery
Charger
External
Power
P604_07_004

ELECTRICAL
For Training Purposes Only
May 03 7-3
PILOT TRAINING GUIDE
Alternating Current (AC) System
Description
Three AC generators provide AC power for the aircraft electrical systems. Two
engine-driven generators power all AC buses during normal operations. An APU
generator provides a source of AC electrical power when the aircraft is on the ground
with the engines off, and during flight if both engine-driven generators become
inoperative.
AC Electrical System
Figure 7-3
GEN
1
GCU
1
GLC1 GLC2
GTC1 GTC2
AC ESS BUS
TX CONTACTOR
UTILITY
BUS CONTACTOR 1
UTILITY
BUS CONTACTOR 2
ADG
GEN
ADG
GCU
ENG.
1
GEN
2
GCU
2
ENG.
2
APU
EMERG AC TX
CONTACTOR
EXT.
AC
APU
GCU
APU
GEN
EXT
PWR
MON
P604_07_002
NOTE: This schematic only displays AC power sources.
Disregard the position of the GLCs and Generator Transfer Contactors (GTCs).
ADG BUS
AC UTILITY
BUS 1
AC BUS 1 AC BUS 2
AC UTILITY
BUS 2
AC
ESS BUS

ELECTRICAL
7-4 For Training Purposes Only
May 03
PILOT TRAINING GUIDE
Components and Operation
Integrated Drive Generators (IDGs)
Two engine-driven IDGs supply 115-volt AC, 400-Hz, three-phase electrical power to
the AC buses. The IDG consists of two subcomponents, a constant speed drive and an
electrical generator.
The generators are identified on the EICAS AC Electrical Synoptic page by the
symbols GEN 1 and GEN 2 (see Figure 7-4). The nominal rating of each generator is
30 kilovolt-amperes (kVA) to an altitude of 35,000 feet MSL, then 25 kVA to 41,000
feet MSL. In the event of a single generator failure, the remaining generator is capable
of supplying sufficient power for operation of the main systems.
The generators are controlled by two-position GEN 1 or GEN 2 switches located on
the ELECTRICAL POWER Panel. Selecting GEN 1 or GEN 2 switch to ON connects
the respective generator to the main AC buses provided they are operating normally.
Selecting the switches to OFF/RESET will disconnect the respective generator from
the main AC buses. The OFF/RESET position can also be used to reset the generator
control circuit when a fault occurs.
Generator Control Unit
Each IDG is controlled and monitored by its respective generator control unit (GCU).
The GCUs provide protection and bus priority logic during normal and non-normal
operations. The engine generator is tripped off and removed from the AC buses if any
of the following conditions occur:
• over- and undervoltage
• over- and underfrequency
• generator and bus overcurrent

ELECTRICAL
For Training Purposes Only
May 03 7-5
PILOT TRAINING GUIDE
GEN 1 and GEN 2 Power
Figure 7-4
AC ELECTRICAL
UTIL BUS 1
BUS 2
GEN
2
GEN
1
APU
BUS 1
UTIL BUS 2
GEN
ESS BUS
P604_07_028
4
115
400
KVA
V
HZ
4
115
400
KVA
V
HZ
0
0
0
KVA
V
HZ
ELECTRICAL POWER
BATT MASTER EXT. POWER
APU GEN GEN 2
OFF/
RESET
OFF/
RESET
ON
ON
OFF
ESS. POWER DC POWER
AC ESS XFER MAIN BUS TIE
AC POWER
GEN 1
OFF/
RESET
AVAIL
IN USE
IN
USE
ON
AUTOXFER
FAIL
OFF
FAIL
OFF
ALTN CLOSED
ON
AC DC

ELECTRICAL
7-6 For Training Purposes Only
May 03
PILOT TRAINING GUIDE
APU Generator
The APU generator supplies 115-volt AC, 400-Hz, three-phase electrical power to the
AC buses during ground operations with the engines off. The APU generator may also
be used in flight as a backup power source to the AC buses following a failure of both
engine generators. The APU generator is mounted on the APU generator adapter and
is driven at a constant speed, maintaining its frequency output at 400 Hz.
The APU generator is identified on the AC Electrical Synoptic page by the symbol
GEN above the APU icon (see Figure 7-5). The nominal rating of the APU generator
is 30 kVA from sea level up to the APU’s maximum operating altitude of 20,000 feet
MSL.
The two-position APU GEN switch located on the ELECTRICAL POWER Panel
controls the APU generator. Selecting the APU GEN switch to ON connects the APU
generator to the main AC buses, providing it is operating normally. Selecting the
switch to OFF/RESET disconnects the APU generator from the main AC buses. The
OFF/RESET position can also be used to reset the generator control circuit when a
fault occurs.
Use of the APU generator in flight is not permitted unless both
main generators have failed or are off-line.
Generator Control Unit
The APU generator is controlled and monitored by the APU generator control unit
(GCU). The APU GCU in conjunction with the engine GCUs provide protection and
bus priority logic during normal and non-normal operations. The APU GENERATOR
is tripped off and removed from the AC buses if any of the following conditions occur:
• over- and undervoltage
• over- and underfrequency
• generator and bus overcurrent
NOTE

ELECTRICAL
For Training Purposes Only
May 03 7-7
PILOT TRAINING GUIDE
APU Power
Figure 7-5
P604_07_029
AC ELECTRICAL
UTIL BUS 1
BUS 2
GEN
2
GEN
1
APU
BUS 1
UTIL BUS 2
0
0
0
GEN
ESS BUS
KVA
V
HZ
0
0
0
KVA
V
HZ
6
113
400
KVA
V
HZ
ELECTRICAL POWER
BATT MASTER EXT. POWER
APU GEN GEN 2
OFF/
RESET
OFF/
RESET
ON
ON
OFF
ESS. POWER DC POWER
AC ESS XFER MAIN BUS TIE
AC POWER
GEN 1
OFF/
RESET
AVAIL
IN USE
IN
USE
ON
AUTOXFER
FAIL
OFF
FAIL
OFF
ALTN CLOSED
ON
AC DC

ELECTRICAL
7-8 For Training Purposes Only
May 03
PILOT TRAINING GUIDE
External AC Electrical Power
Description
The aircraft is capable of being powered by an external AC power source when both
engines and APU are off. External AC electrical is connected at a receptacle located
on the forward right side of the fuselage.
External AC Receptacle
Figure 7-6
Operation
External AC ground power is controlled by the EXT POWER switch/light located on
the ELECTRICAL POWER Panel. When connected, the external AC ground power is
checked by an external power monitor for proper voltage, frequency, and phase. When
the external power is within limits, the green AVAIL annunciator on the EXT POWER
switch/light illuminates (see Figure 7-7).
When the EXT POWER switch/light is pressed with the AVAIL annunciator
illuminated, external AC electrical power is connected to the aircraft main AC buses
via the auxiliary power/external power contactor (AP/EPC).
External AC ground power is identified on the AC Electrical Synoptic page by the
symbol EXT AC. This symbol appears only if external AC power is connected to the
aircraft (see Figure 7-7).
P604_07_055

ELECTRICAL
For Training Purposes Only
May 03 7-9
PILOT TRAINING GUIDE
External AC Electrical Power
Figure 7-7
ELECTRICAL POWER
BATT MASTER EXT. POWER
APU GEN GEN 2
OFF/
RESET
OFF/
RESET
ON
ON
OFF
ESS. POWER DC POWER
AC ESS XFER MAIN BUS TIE
AC POWER
GEN 1
OFF/
RESET
AVAIL
IN USE
IN
USE
ON
AUTOXFER
FAIL
OFF
FAIL
OFF
ALTN
CLOSED
ON
AC DC
P604_07_031
AC ELECTRICAL
UTIL BUS 1
BUS 2
GEN
2
GEN
1
APU
BUS 1
UTIL BUS 2
0
0
0
GEN
ESS BUS
KVA
V
HZ
0
0
0
KVA
V
HZ
0
00
00
KVA
VV
HZHZ
EXT
AC
116
400
V
HZ
EXTERNAL AC POWER SUPPLYING MAIN AC BUSES
P604_07_030
AC ELECTRICAL
UTIL BUS 1
BUS 2
GEN
2
GEN
1
APU
BUS 1
UTIL BUS 2
0
0
0
GEN
ESS BUS
KVA
V
HZ
0
0
0
KVA
V
HZ
0
00
00
KVA
VV
HZHZ
EXT
AC
116
400
V
HZ
EXTERNAL AC POWER CONNECTED TO AIRCRAFT
ELECTRICAL POWER
BATT MASTER EXT. POWER
APU GEN GEN 2
OFF/
RESET
OFF/
RESET
ON
ON
OFF
ESS. POWER DC POWER
AC ESS XFER MAIN BUS TIE
AC POWER
GEN 1
OFF/
RESET
AVAIL
IN USE
IN
USE
ON
AUTOXFER
FAIL
OFF
FAIL
OFF
ALTN CLOSED
ON
AC DC

ELECTRICAL
7-10 For Training Purposes Only
May 03
PILOT TRAINING GUIDE
AC Electrical Power Distribution
Description
115-volt AC electrical power from the aircraft generators and APU generator is
distributed to five AC buses through circuit breaker panels. Monitoring of system
status is done using the EICAS AC Electrical Synoptic page.
The aircraft AC bus system consists of the following five buses:
• AC BUS 1 (Main)
• AC BUS 2 (Main)
• AC ESS BUS (Essential)
• AC UTILITY BUS 1
• AC UTILITY BUS 2
EICAS AC Electrical Synoptic Page
Figure 7-8
AC ELECTRICAL
UTIL BUS 1
BUS 2
GEN
2
GEN
1
APU
BUS 1
UTIL BUS 2
GEN
ESS BUS
P604_07_032
4
115
400
KVA
V
HZ
4
115
400
KVA
V
HZ
0
0
0
KVA
V
HZ
AC UTILITY BUS 1
AC BUS 1 (Main)
AC ESS BUS (Essential)
AC UTILITY BUS 2
AC BUS 2 (Main)

ELECTRICAL
For Training Purposes Only
Jan 04 7-11
PILOT TRAINING GUIDE
Components and Operation
AC BUS 1 and AC BUS 2
AC BUS 1 and AC BUS 2 are the main AC buses of the aircraft, and receive power
from any of the three generators or from external AC power. AC BUS 1 normally
supplies power to the AC ESS BUS and AC UTIL BUS 1. AC BUS 2 normally
powers AC UTIL BUS 2.
Bus Priority
AC BUS 1 and AC BUS 2 are protected by a bus priority logic to ensure that the buses
remain powered at all times. The generator control units (GCUs) determine the bus
priority logic for AC BUS 1 and AC BUS 2 via the generator line contactors (GLCs)
and generator transfer contactors (GTCs). The bus priority logic for AC BUS 1 and
AC BUS 2 is as follows:
• on-side engine-driven generator (example: AC BUS 1 powered by GEN 1)
• APU generator
• cross-side engine-driven generator (example: AC BUS 1 powered by GEN 2)
• external AC Power
According to the above priority logic, the GLCs and GTCs will automatically tie the
main AC buses to any of the available AC power sources, to ensure the main AC buses
remain powered at all times.
AC BUS 1(2) Automatic Transfer (AUTOXFER) Switch/Lights
The flight crew may manually inhibit the automatic bus transfer priority logic by
pressing the appropriate AUTOXFER switch/light located on the ELECTRICAL
POWER Panel. This prevents the corresponding AC BUS from being powered by any
source except its on-side engine-driven generator. This may be used to isolate a main
AC bus in the event of an electrical emergency (example: electrical smoke or fire).
Selection of the AUTOXFER switch/light is indicated by illumination of the
corresponding white OFF annunciator on the switch/light and the white AUTO XFER
OFF icon on the AC Electrical Synoptic page (see Figure 7-9).
Should a bus fault or generator overcurrent condition occur on a main AC bus, the
automatic bus transfer priority logic will be inhibited, isolating the fault from the
remaining AC electrical system. This condition is indicated by the AC 1(2)
AUTOXFER caution EICAS message, illumination of the corresponding amber FAIL
annunciator on the AUTOXFER switch/light, and the amber AUTO XFER FAIL icon
on the AC Synoptic page (see Figure 7-9).

ELECTRICAL
7-12 For Training Purposes Only
Jan 04
PILOT TRAINING GUIDE
AC BUS Automatic Transfer
Figure 7-9
ELECTRICAL POWER
BATT MASTER EXT. POWER
APU GEN GEN 2
OFF/
RESET
OFF/
RESET
ON
ON
OFF
ESS. POWER DC POWER
AC ESS XFER MAIN BUS TIE
AC POWER
GEN 1
OFF/
RESET
AVAIL
IN USE
IN
USE
ON
AUTOXFER
FAIL
OFF
FAIL
OFF
ALTN CLOSED
ON
AC DC
P604_07_034
AC ELECTRICAL
UTIL BUS 1
BUS 2
GEN
2
GEN
1
APU
BUS 1
UTIL BUS 2
GEN
ESS BUS
4
115
400
KVA
V
HZ
0
0
0
KVA
V
HZ
0
0
0
KVA
V
HZ
AUTO
XFER
FAIL
SHED
AC BUS 2 AUTOMATIC TRANSFER FAILURE
ELECTRICAL POWER
BATT MASTER EXT. POWER
APU GEN GEN 2
OFF/
RESET
OFF/
RESET
ON
ON
OFF
ESS. POWER DC POWER
AC ESS XFER MAIN BUS TIE
AC POWER
GEN 1
OFF/
RESET
AVAIL
IN USE
IN
USE
ON
AUTOXFER
FAIL
OFF
FAIL
OFF
ALTN CLOSED
ON
AC DC
P604_07_033
AC ELECTRICAL
UTIL BUS 1
BUS 2
GEN
2
GEN
1
APU
BUS 1
UTIL BUS 2
GEN
ESS BUS
4
115
400
KVA
V
HZ
4
115
400
KVA
V
HZ
0
0
0
KVA
V
HZ
AUTO
XFER
OFF
AC BUS 2 AUTOXFER SWITCH/LIGHT SELECTED OFF

ELECTRICAL
For Training Purposes Only
May 03 7-13
PILOT TRAINING GUIDE
AC ESS (Essential) Bus
The AC ESS BUS supplies power to the equipment essential for flight. It is normally
powered by AC BUS 1, but may also be powered by AC BUS 2 or the ADG BUS. The
AC ESS BUS supplies power to ESS TRU 1, which provides DC power to the DC
ESS BUS and the BATT BUS.
Refer to the ADG section in this chapter for information on the ADG BUS.
AC ESS Bus Transfer
If a loss of power on AC BUS 1 is sensed, the AC ESS BUS is automatically
transferred to AC BUS 2. When an automatic transfer to AC BUS 2 occurs, the AC
ESS XFER switch/light located on the ELECTRICAL POWER Panel illuminates and
the AC ESS ALTN status EICAS message appears (see Figure 7-10).
If the automatic transfer fails to occur, the AC ESS BUS can be manually transferred
to AC BUS 2 by pressing the AC ESS XFER switch/light.
AC Essential Bus on Alternate Source
Figure 7-10
ELECTRICAL POWER
BATT MASTER EXT. POWER
APU GEN GEN 2
OFF/
RESET
OFF/
RESET
ON
ON
OFF
ESS. POWER DC POWER
AC ESS XFER MAIN BUS TIE
AC POWER
GEN 1
OFF/
RESET
AVAIL
IN USE
IN
USE
ON
AUTOXFER
FAIL
OFF
FAIL
OFF
ALTN CLOSED
ON
AC DC
P604_07_035
AC ELECTRICAL
UTIL BUS 1
BUS 2
GEN
2
GEN
1
APU
BUS 1
UTIL BUS 2
GEN
ESS BUS
2
115
400
KVA
V
HZ
4
115
400
KVA
V
HZ
0
0
0
KVA
V
HZ
AUTO
XFER
FAIL

ELECTRICAL
7-14 For Training Purposes Only
May 03
PILOT TRAINING GUIDE
AC Utility Buses
AC UTILITY BUS 1 and 2 receive power from AC BUS 1 and 2 respectively. The AC
utility buses supply AC power to nonessential cabin equipment.
Utility Bus Shedding
During single-generator operation in flight, AC UTILITY BUS 1 and 2 are
automatically load shed to reduce the electrical load on the remaining generator.
During ground operations, AC UTILITY BUS 1 and 2 are load shed when a single
generator (or external AC power only) is supplying AC power and the flaps are not
retracted.
Load shedding of AC UTILITY BUS 1 and 2 is indicated by the appearance of AC
UTIL 1(2) OFF status EICAS messages and the SHED icons on the AC Electrical
Synoptic page (see Figure 7-11).
AC Utility Bus Shedding
Figure 7-11
P604_07_036
AC ELECTRICAL
UTIL BUS 1
BUS 2
GEN
2
GEN
1
APU
BUS 1
UTIL BUS 2
GEN
ESS BUS
0
0
0
KVA
V
HZ
0
0
0
KVA
V
HZ
7
113
401
KVA
V
HZ
AUTO
XFER
FAIL
SHED SHED
AC UTIL 2 OFF
AC UTIL 1 OFF
EICAS SECONDARY
DISPLAY

ELECTRICAL
For Training Purposes Only
Jan 04 7-15
PILOT TRAINING GUIDE
Air-Driven Generator (ADG)
Description
The ADG provides 115-volt, 400-Hz, 15-kVA power to the AC ESS BUS and 3B
hydraulic pump, in the event of a complete loss of AC power in flight. The ADG is
located in the forward right fuselage beside the nose gear and is deployed
automatically or manually. Once deployed, the ADG can only be restowed when the
aircraft is on the ground (see Figure 7-12).
Air-Driven Generator (Wet ADG Shown)
Figure 7-12
ADG Ground
Safety Lockpin
UPLOCK ASSEMBLY
Auto Release
( Squib Cartridge
Solenoid)
Wet ADG - /
Dry ADG -
P604_07_003
Manual
Release
Ejection
Jack
Assembly
Manual
Restowable
Pump Assembly
Air-Driven
Generator
Assembly
Ejection
Jack
Assembly
Manual
Retraction
Pump
Assembly
AIR - DRIVEN DRY GENERATOR
(Aircraft 5408 and subsequent)
AIR - DRIVEN WET GENERATOR
(Aircraft 5301 to 5407)
Air-Driven
Generator
Assembly

ELECTRICAL
7-16 For Training Purposes Only
May 03
PILOT TRAINING GUIDE
Components and Operation
Air-Driven Generator
The ADG consists of an AC generator mounted on a pivoted support leg and a
variable-pitch two-bladed propeller that turns in the airstream. There are two versions
of the ADG.
Airplanes 5301 to 5407
On airplanes 5301 to 5407, constant speed of the generator is achieved by
hydraulically controlling the propeller pitch angle. This ADG is commonly referred to
as the “wet ADG”. Wet ADG operation is airspeed-limited (refer to the Airplane
Flight Manual Limitations).
On landing with the wet ADG deployed, use gentle deceleration
to prevent the ADG from swinging forward and contacting the
fuselage.
Airplane 5408 and Subsequent
On airplanes 5408 and subsequent, the constant speed of the ADG is achieved by
using a counterweight system to control the propeller pitch angle. This ADG is
commonly referred to as the “dry ADG”.
ADG Generator Control Unit
The ADG generator is controlled and monitored by the ADG generator control unit
(GCU). The ADG GCU provides the following functions:
• monitors and controls ADG voltage output
• protects against overvoltage, overfrequency and underfrequency to the ADG BUS
• provides a signal to the ADG Auto Deploy Control Unit to energize the HYD
PUMP 3B Transfer Contactor, Emergency AC Transfer Contactor, and Emergency
DC Transfer Contactor when the ADG voltage and frequency are within limits
NOTE