E175 Systems

2 IDG's (Integrated Drive Generators)
115 vAC, 400 Hz, 40 kVA

Sundstrand APS 2300
115 vAC, 400 Hz, 40 kVA

115 vAC, 400Hz, 15 kVA

-Onside (IDG)
-Inside (APU)
- Outside (GPU)
-Cross-Side (Opposite IDG)

Only AC ESS Bus

If both AC buses lose power inflight (electrical emergency)

(Secondary Power Distribution Assemblies)
-Electrical load mgmt unit
-Receives power from ICC's
-Distributes power according to system logic

(Integrated Control Center)
-4 installed in various electronic bays
-Collect & confirm power is safe
-Sends power to SPDA's

-Eng 1A/2A Fire Extinguisher
-Eng Fuel Shutoff Valve 1
-Hyd Shutoff Valve 1
-Eng 1 oil level indication
-Courtesy/Service Lights
-DC Ceiling Lights

-Eng 1B/2B Fire Extinguisher
-Eng Fuel Shutoff Valve 2
-Hyd Shutoff Valve 2
-Eng 2 oil level indication
-CMC (Central Maint. Computer)
-Panel Refuel
-Water & Waste System

-2 independent networks
-Redundancy and fault isolation

-Bus ties automatically connect to provide no system degradation

-2 Integrated Drive Generators (IDG)
-Auxilliary Power Unit (APU)
-Inverter
-Ram Air Turbine (RAT)
-AC GPU receptacle

2 IDG's (Integrated Drive Generators)
115 vAC, 400 Hz, 40 kVA

A constant speed drive (CSD) attaches the IDG to the accessory gear box

Each has a generator control unit (GCU)

Yes

2 IDG's (Integrated Drive Generators)
115 vAC, 400 Hz, 40 kVA

No. This is a maintenance function

-To power the AC busses and AC ESS Bus
which...
-Power the 3 Transformer Rectifier Units (TRU's) 1,2 & ESS

To convert 115VAC to 28VDC

Yes

-GPU button displays AVAIL
-GPU icon displayed on synoptic page
-Once GPU button pushed in IN USE is displayed

The ground service bus is being powered by the GPU even though cockpit GPU button has not been pushed in.

Remember to deselect the GPU button before the next GPU connection

Eng exciters 1A and 2A

approx. 10 minutes

The respective IDG takes priority over the GPU and will now power it's side of the network while the GPU continues to power the other side.

-For APU start when batteries <22.5 VDC or
-If battery temp is <20 degrees Celsius

-20 degrees Celsius

18 volts

-BATT 2 powers the APU start bus
-BATT 1 powers the FADEC & EICAS for monitoring

Converts 28VDC from the batteries to 115VAC to power the AC STANDBY BUS when an AC source is not available.

Powered by BATT 2 or DC Buses

Airflow turns the RAT propeller which spins the generator turbine inside.

-Automatically deploys if AC Busses are not powered
OR
-Manually by pilot

approx. 8 seconds

No. Batteries supply power to the DC ESS Busses and AC Standby Bus

ESS Busses

-130 KIAS or else
-Load shedding occurs below this speed

When the RAT is deployed

-4 Integrated Control Centers (ICC's)
-2 Secondary Power Distribution Assemblies
(SPDA's)

An electrical control device which provides power distribution and protection for electrical loads.

An electrical load-management unit powered by the ICC's that distributes electrical loads to aircraft systems according to distribution logic.

-ICC CB's can only be reset by Maintenance
-SPDA CB's can be reset bia the MCDU

-Keeps fuel pumps submerged
-Ensures constant fuel flow to respective engine

-2 engine driven
-2 ejector
-6 scavenge
-2 AC electric
-1 DC electric

In the collector tanks

The engine driven pumps

-Allows fuel to both engines from one tank
-Used to correct fuel imbalance

Powered by BATT 2 or DC Buses

2 integral tanks

Left wing tank (-40 C min)

-Primary ejector pump
-ACMP
-DCMP (right tank only)
-3 scavenge ejector pumps

-Venturi pump with no moving parts and no electrical power
-Powered by motive flow only

-Back-up pump in case primary ejector pump fails
-Engine start
-Crossfeed operations

Used for APU or eng start if AC power or the ACMP is not available.

Maintains fuel level in the collector box

Associated primary ejector pump

-Collects fuel during wing-down maneuvers and returns it to the main tanks once the wings are level
-Equalizes tank pressure with atmosphere in flight and during refueling

No

-Crossfeed valve is opened
-Commands the ACMP 2 to "ON" to provide fuel from the right tank to both engines

Pull the associated engine fire extinguishing handle

660 lb. of fuel remaining in the associated tank

-DC Fuel Pump (tank 2)
-AC Fuel Pump (tank 2)
-Tank 2 ejector pump
-Tank 1 ejector pump via X-Feed
-Tank 1 AC Fuel Pump via X-Feed

-Engines
-APU
-Cargo Compartments
-Lavatories

-Yes
-Cockpit 1 hand-held Halon fire extinguisher
-Cabin 3 hand-held Halon fire extinguishers (1 fwd & 2 aft)
-Cabin 1 hand-held Water fire extinguisher

-Engines 2 Halon fire bottles
-APU 1 Halon fire bottle dedicated to the APU only

Yes

-Engine Detection DC ESS
-Engine Protection HOT BATT
-APU Detection DC ESS
-APU Protection DC ESS

-Engine 8 pneumatic fire detectors (2 loops) per engine
-APU 2 pneumatic fire detectors (2 loops)

-Closes engine fuel SOV
-Closes engine Hydraulic SOV
-Closes engine Bleed SOV

-Fire Bell
-Red stripe in the EMER STOP button
-APU FIRE is displayed on the EICAS

Only on the ground

-APU shuts off immediately without a 1-minute cool-down
-APU fuel SOV closes
-APU FIRE EXTG button illuminates

After one minute the APU FIRE EXTG button illuminates

No

-3 detectors in the FWD compartment
-2 detectors in the AFT compartment

-Recirculation fan shuts off
-Ventilation outflow valve closes

-Prevents oxygen from entering the compartment
-Prevents Halon agent from escaping into the aircraft's cabin

-2 bottles used for both compartments
-1 high-rate bottle and 1 low-rate bottle

-High-rate bottle saturates the compartment immediately
-Low-rate bottle maintains saturation over a duration of time

60 minutes

No. Only one compartment may be selected (FWD or AFT)

-High-rate bottle discharges immediately
-Low-rate bottle discharges after one-minute if the airplane is in flight
-If airplane is on the ground (WOW) the low-rate bottle will NOT automatically discharge

Yes, by pushing the extinguishing button again.

The extinguishing button must be pushed again.

-Yes. The high rate bottle extinguishing button must be pushed twice, once to arm the bottle and once to discharge the bottle.
-The low-rate bottle automatically discharges after one minute if in flight.

Heat-sensitive extinguishers in the lav waste bins automatically discharge if a predetermined temperature is reached.

Sundstrand APS 2300

-Constant speed
-Single-stage impeller with a 2-stage axial-flow turbine
-Independent oil system

A dedicated FADEC

-Right fuel tank
-Left fuel tank through crossfeed valve

-Batteries "ON" only DC fuel pump in right tank
-AC powered airplane ACMP 2
-Right engine running Ejector fuel pump

Yes

-Initiates normal APU shutdown
-1-minute cool down
-No pneumatics (electrics only for 1 minute)

Yes, by moving the START switch back to "ON" before the 1-minute cool down is over.

-APU emergency stop button
-No 1-minute cool down period

The APU will shut down immediately

-Overspeed
-Underspeed
-FADEC critical fault
-Fire
-Overheat
-Low oil pressure

-Overspeed
-Underspeed
-FADEC critical fault

No

System 1 and 2 each have 2 accumulators per system.
One for shock absorption and the other for emergency parking brake use.

If in AUTO and only engine 1 is operating, upon releasing the parking brake ACMP 2 will activate to provide hyd power for nose wheel steering and the inboard brakes.

-Engine driven pump failure OR
-Flaps selected to any position greater than 0*

-Flaps selected to any position greater than 0* AND
-Thrust levers set to takeoff thrust or groundspeed >50 kts

Temporarily provides hydraulics to the flight controls during an electrical emergency (from the beginning of RAT deployment until AC ESS Bus powers the AC pump 3A)

-3 independent systems
-Hyd 1, Hyd 2, and Hyd 3

-Flight controls
-Spoilers
-Landing gear
-Nose wheel steering
-Wheel brakes
-Thrust reversers

No

6 total:
-2 Eng driven pumps
-4 AC motor pumps

-Reservoir
-Pumps
-Accumulators

-Helps to maintain constant pressure by covering transient demands
-Helps to avoid pump cavitation

-Landing gear
-Nose wheel steering
-Inboard brakes

-Power Transfer Unit
-Mechanical pump that uses Hyd sys 1 power to provide Hyd sys 2 pressure

To allow landing gear retraction in the event of an Eng 2 or Eng driven pump failure.

During takeoff and landing with flaps >0 IF
-Eng 2 fails
OR
-Eng driven pump 2 fails

Releasing the parking brake automatically activates AC Hyd pump 2

Back-up for the Flight Controls

-Hyd AC motor pump 3A is primary and has no automation
-Hyd AC motor pump 3B is a back-up and automatically activates if AC motor pump 3A fails

Hyd AC motor pump 3A only

-Hyd system 3 accumulator
-After 8 seconds the RAT will power Hyd AC motor pump 3A

No. A flow limiter valve is used to reduce hyd fluid flow and limits Hyd pump electrical power draw to prevent a RAT stall.

approx. 6 applications

-ECS (heating & cooling)
-Engine Start
-Pressurization
-Eng & Wing Anti-ice
-Water pressure
-Hot air leak detection

-ECS on the ground
-Engine starting on the ground
-Electrical source (<FL330)
-Assist with engine start (<FL210)
-Bleed source for pressurization, heating, and cooling (<15,000 ft. MSL)

One controller with 2 channels which control the respective onside system.

The remaining channel is able to control the entire AMS.

-Engine bleeds
-APU bleed
-External pneumatic source

-ECS (heating & cooling)
-Engine start
-Engine & wing anti-icing
-Water pressurization

-ECS on the ground
-Engine start on the ground

Lower fairing between the wings

No. A check valve prevents flow-back.

-6th and 10th stage compressors (Eng Bleed valve and High stage valve respectively)
-System alternates between valves to regulate an adequate and safe pressure

about 45 psi

Cools the bleed air coming from the engine to the AMS

-Ground N1 fan
-Flight N1 fan or ram air

-Engine bleeds and packs
-APU bleed
-Plumbing for the wing & eng anti-icing systems

Yes, but if one fails the other will work alone to detect an overheat

-2 independent packs (left & right)
-Each engine provides bleed air to its's respective pack

Yes, up to FL 310

Yes, through a crossbleed valve

52% FRESH air to 48% RECIRCULATED air

-Cockpit switch
-Smoke detected in the recirc bay
-DUMP button is pressed
-Respective pack is commanded "OFF"

3 fans each pull air from cabin to bay

Natural air-flow from cabin to bay

-Both packs commanded or failed OFF below 25,000 ft. (via left side and electronically controlled)
-Ram air pressure greater than cabin pressure (differential pressure via right side) via one-way check valve
No electrical power required

2 channels, one active and one in standby mode

FMS or can be manually selected

-Commands both ECS packs OFF
-Opens outflow valve and raises the cabin to 12,400 ft. at a rate of 2,000 fpm

-Yes, by using manual mode
-Cabin altitude will rise due to natural leak

No

-Onside engine
-Opposite side engine
-APU (if avail)

APU has priority if:
-Aircraft is on the ground
-Wheel speed <50 kts
-Opposite eng bleed pressure is not enough for eng start

-Only one side bleed source is available
-Eng 2 start in the air
-Eng 1 start in the air (if APU is not avail)

-Any eng start if APU is the bleed source
-Eng start on the ground
-Respective bleed system duct leak
-Bleed air source not avail for the pack
-Thrust Levers set to MAX on Takeoff
-REF Anti-ice set to ALL on Takeoff
-REF ECS set to OFF on MCDU (APU is OFF)

Thrust Levers NOT at MAX and:
-Airplane is 500 AFE with both engs operating
-Airplane is >9,700 ft. MSL with one eng operating

-Both recirc fans deactivate
-Cargo recirc fan deactivates
-Cargo outflow valve closes

-FMS before takeoff or CPCS calculates using ambient pressure
-LFE may be manually imputted

-Green FMS input
-Cyan Manual input (an "M" will be in front of LFE)

Cabin is scheduled back to the takeoff altitude if:
-Airplane stops climbing & begins a descent,
AND
-Airplane has not climbed >5,000 ft AFE or >10,000 ft MSL

-Bleed air heat
-Electric heat

-Engine lips
-3 outboard slats

-Pitot-static system
-Windshields
-Water lines
-Pressurization static port

-Yes. The crossbleed valve opens to provide symmetrical ice protection for both wings
-The failed engine does not receive heat to the engine lip

One. There are two for redundancy

5 minutes

Not until 1,700ft. or 2 minuites after takeoff (whichever happens first)

No

-Engine inlets
-Wing leading edge
-Smart probes
-Windshields
-Water & waste drain systems

Yes, under normal conditions

Yes

-2 ice detectors
-Vibrating sensor element changes frequency when ice builds up around it
-One ice is detected, sensor element heats, ice melts, the normal vibration resumes and the heating process stops
-Cycle repeats as ice rebuilds on the probes

10th High stage valve (HSV)

-Engines are independent
-Wings from onside bleed

The crossbleed automatically opens

-<10*C "ENG"
-<5*C "ALL"

-Engine anti-ice "ON" when engines are running
-Wing anti-ice "ON" at 40 kts wheel speed

1,700 ft. AGL or 2 minutes after takeoff (whichever happens first)

1,700 ft. AGL or 5 minutes after takeoff (whichever happens first)

-On ground inhibited
-In flight Left side is heated (right side heats if left has failed)

Activates the associated wiper in 8-second intervals

-The wiper will stop
-To reset wiper move switch to "OFF"

When an engine is running

Yes, but maintenance performs this test

-Bleeds................OFF
-Stab Trim...........Full nose down
-Flaps...................UP
-Engines & APU...ON or OFF

General Electric CF34-8E
High Bypass, Axial-flow, two stage, turbofan

13,800 lbs normal
14,200 lbs using reserve mode (RSV)
under isa conditions

-ESS powered below 50% N2
-PMA powered above 50% N2

Each FADEC has 2 channels:
-1 Active
-1 Standby

Max N1 for selected engine thrust mode

Max N1 allowed for current thrust rating and
current operating conditions

value requested based on TLA (Thrust Lever Angle)

-N2 Rotation
-7% N2 Ignition
-20% N2 Fuel flow (light off within 5 secs)
-Normal acceleration & oil pressure
-50% N2 Ignition OFF & Starter cut-out
-Normal acceleration & stabilization

Controlled by FADEC

Provides max thrust (RSV) when armed, thrust levers TOGA and:
-Difference between N1 values >15%
or
-One engine failure during takeoff or go-around
or
-Windshear detection

120*C

-Single-stage fan
-4-stage LP turbine

-10-stage compressor (gas generator)
-2-stage HP turbine

2

-Ground.....................1 igniter (switch in AUTO)
-Flight........................2 igniters (switch in AUTO)

Activates both igniters ON THE GROUND OR IN FLIGHT

-The switch may be moved to the OFF position but the FADEC DISREGARDS THE COMMAND
-The OFF position is used for dry-motoring on the ground only

-A two channel FADEC
-One channel is active and the other channel remains in standby as a backup

No. They automatically alternate with each engine start.