06 elect

7/28/2019 06 Elect

1/20

7/28/2019 06 Elect

2/20

7/28/2019 06 Elect

3/20

Citation I/II/SII For training onlyMay 1998

Electrical System

DC Electrical SystemCII 002 to 626

AC BUSES

RH COCKPIT CB PANELLH COCKPIT CB PANEL

FD 2HSI 1RADARRMI 1RMI 2V GYRO 1V GYRO 2

RH CROSSOVER BUS

RH MAIN BUSLH MAIN BUS

GROUNDPOWERRELAY

BATTERYRELAY

EMERPWR

RELAY

225A

75A75A

35A 35A

80A80A

LEFT CB PANEL

RIGHT CB PANEL

AFT J-BOX

BATT

EMER BUS

L GEN

RESET

OFF

LH CROSSOVER BUS

15AINVERTER 1

15AINVERTER 2

BATTERY DISABLE RELAY(CROSS GEN START)

L/R GEN OFF

R GEN

RESET

OFF

BATTERYDISCONNECT RELAY

24V

(EXTERNAL POWER START)

LH STARTRELAY

RH STARTRELAY

RHPOWERRELAY

LHPOWERRELAY

002 - 549

550 - 626

LHGEN

225A

OVER VOLTAGEOVER CURRENT

32.5V

1200A28.0V1000A

BATT

EMER

OFF

10

20 30

40D.C.

VOLTS

0

100200

300

400

D.C. AMP

0

100200

300

400

D.C. AMP

28.5V

400A

BATTERY BUS

HOT BATTERY BUS

GCU

RHGEN

GCU

LEFT MAIN EXT BUS RIGHT MAIN EXT BUS

GENOFF

LH RH

LH POWER JUNCTION BOX CIRCUIT BREAKERS

EMER EXIT LIGHTINDIRECT LIGHTSLH AMMETERLH BOOST PUMPLH BUS SENSE

LH GEN ANN LIGHTLH GEN POWER RELAYLH LANDING LIGHTLH START LIGHTLH VOLTMETER

RH POWER JUNCTION BOX CIRCUIT BREAKERS

CABIN LIGHTSIGNITION POWERLOCATOR BEACONRECOG LIGHTSRH AMMETERRH BATTERY VOLTAGE

RH BOOST PUMPRH BUS SENSERH EMERGENCY BUSRH GEN ANN LIGHTRH GEN POWER RELAYRH LANDING LIGHT

RH MAIN BUS EXTENSION

LH CROSSOVER BUS

LH MAIN BUS EXTENSION

RH CROSSOVER BUS EMERGENCY BUS (28V DC)

OXYGEN/SEAT BELT CHIMESREFRESHMENT BARTAIL LIGHTTAILCONE LIGHT

RH START LIGHTRH VOLTMETERSHAVER/TOILET

4

2

5

6

ANGLE-OF-ATTACK HEATERBATT TEMP WARNINGCENTER PANEL LIGHTSCLOCKEL PANEL LIGHTSEMERGENCY PRESSENGINE SYNCENTERTAINMENT CENTERFLT/HR EQUIP COOLLDG GEAR WARNINGLH IGNITIONNAV LIGHTSPITCH TRIMRH ALT VIBRATOR

RH BOOST PUMPRH ENGINE ANTI-ICERH FIRE DETECTRH FIREWALL SHUTOFFRH THRUST REVERSERRH TURN AND BANKRH PANEL LIGHTSRH PITOT STATICSPEEDBRAKESTEMP CONTROLWARNING LIGHTS 1WING INSPECTION LIGHTW/S BLEED AIRW/S BLEED AIR TEMP

AC INVERTER NO. 1ANGLE-OF-ATTACKANTI COLLISIONCABIN DEFOG FANFLAP CONTROLFLAP MOTORGEAR CONTROLLH BOOST PUMPLH BUS NO. 1,2,3LH ENGINE ANTI-ICELH FIRE DETECTLH F/W SHUTOFFLH PANEL LIGHTSLH PITOT STATIC

LH STARTLH TURN AND BANKLH THRUST REVERSERNORM PRESSURIZATIONNOSEWHEEL RPMOUTSIDE AIR TEMPERATUREOVERSPEED WARNRH CB PANELRH IGNITIONSKID CONTROLSTANDBY GYROSURFACE DE-ICEWARNING LIGHTS 2W/S ALCOHOL

COMM 1DG 2FLOODLIGHTSNAV 2

ADF 1AREANAVAUDIO 1AUTOPILOTDIRECTIONAL GYRO 1DME 1FD 1LH FAN SPEEDLH FUEL FLOWLH FUEL QTY

LH ITTLH OIL PRESSLH OIL TEMPLH TURB SPEEDNAV 1PHONERADIO ALTIMETERRMI 1TRANSPONDER 1VLF/NAV

AC INVERTER NO. 2AC SWITCHADF 2AUDIO 2COMM 2COMM 3DME 2FD 2LH CB PANELRADARRH BUS NO. 1,2,3

RH FAN SPEEDRH FUEL FLOWRH FUEL QUANTITYRH ITTRH OIL PRESSURERH OIL TEMPERATURERH STARTRH TURBINE SPEEDRMI 2TRANSPONDER 2

AC MONITORADF 1ADF 2ADI 1AIR DATAAUTOPILOTFD 1

3

HOT BATTERY BUS

BATTERY RELAYEMERGENCY POWER RELAYEMERGENCY LIGHTING BATTERY PACKEMERGENCY LOCATOR BEACON (OPTIONAL)EXIT LIGHTSLH/RH NORMAL START IGNITIONNOSE AND TAIL BAGGAGE LIGHTSTAIL CONE LIGHTSVOLT METER (BATTERY SWITCH IN BATT OR EMER)

1LH PRESS BLKHD CBs

L WING ANTI-ICE (5)

RH PRESS BLKHD CBs

R WING ANTI-ICE (5)

LHGEN

RHGEN

BATT

VOLTAGE SEL

ENGINE START

DISENGAGELH

STARTDISC

ENGINE START

DISENGAGE RH

STARTDISC

2

4 5

6

3

1

4B-3

7/28/2019 06 Elect

4/20

4B-4 For training only Citation I/II/SIIJune 1997

7/28/2019 06 Elect

5/20

Electrical System


DC Electrical SystemUnit 627 and subsequent

ADI 1

ADI 2

AIR DATA

AP

EFIS 1/2

FD 1

FD 2

GPWS

HSI 1

HSI 2

NAV 1

NAV 2

RADAR

RMI/ADF 1

RMI/ADF 2

V GYRO 1

V GYRO 2

AC BUSES


RH CROSSOVER BUS


GROUNDPOWERRELAY

BATTERYRELAY

EMERPWR

RELAY

225A

75A75A

35A 35A

80A80A

LEFT CB PANEL

RIGHT CB PANEL

AFT J-BOX

BATT

EMER BUS

L GEN

RESET

OFF

LH CROSSOVER BUS

15AINVERTER 1

15AINVERTER 2


R GEN

RESET

OFF


24V


LH STARTRELAY

RH STARTRELAY

RHPOWERRELAY

LHPOWERRELAY

550 - 626

LHGEN

225A


32.5V

1200A28.0V1000A

BATT

EMER

OFF

10

20 30

40D.C.

VOLTS

0

100200

300

400

D.C. AMP

0

100200

300

400

D.C. AMP

28.5V

400A

BATTERY BUS

HOT BATTERY BUS

GCU

RHGEN

GCU


GENOFF

LH RH

LHGEN

RHGEN

BATT

VOLTAGE SEL

ENGINE START

DISENGAGELH

STARTDISC

ENGINE START

DISENGAGE RH

STARTDISC

2

4 5

6

3

1


AFT/FWD COMP LIGHTBAREMER LIGHTENTERTAINMENT CTRINDIRECT LIGHTS

LH AMMETERLH ANNUNCIATORLH BOOST PUMPLH BUS SENSELH GENERATOR


BATTERY VOLTAGECABIN LIGHTSELTEMER POWERFLOOD COOLINGIGNITION POWER

RH AMMETERRH ANNUNCIATORRH BOOST PUMPRH BUS SENSERH GENERATORRH LANDING LIGHT

RH MAIN BUS EXTENSIONAC INVERTER NO. 2

ADF 2COMM 2

DME 2EFIS 2 (DUAL EFIS)

EFIS 2 CONT (DUAL EFIS)EHSI 2 (DUAL EFIS)

EADI 2FD 2

LH CB PANELMFD SYM GENMFD DISPLAY

PHONE

RADAR

RH BUS NO. 1,2,3RH FAN SPEED

RH FUEL FLOWRH FUEL QUANTITY

RH ITTRH OIL PRESSURE

RH OIL TEMPERATURERH START

RH TURBINE SPEEDRMI 2 (DUAL EFIS)TRUE AIRSPEED

TRANSPONDER 2

AC WARN

ADF 1AFIS

AUTOPILOTCOMM 3

DIRECTIONAL GYRO 1DME 1

EADI 1EFIS 1

EFIS 1 CONTROLLER

EHSI

FD 1FMS

NAV 1RADAR ALTIMETER

RMI 1TRANSPONDER 1

VLF

LH CROSSOVER BUS


RH CROSSOVER BUS

CENTER PANEL LIGHT

EMERGENCY PRESSURIZATIONEQUIPMENT COOLING FAN

FLIGHT HOUR METERLH BOOST PUMP

LH FIRE DETECTLH FIREWALL SHUTOFF

LH IGNITIONOVERSPEED WARNING

RH CLOCKRH ENGINE ANTI-ICE

RH ALTIMETER VIBRATORRH PANEL LIGHTS

RH PITOT STATIC (ANTI-ICING)RH THRUST REVERSER

SURFACE DE-ICEWARNING LIGHTS 2

WINDSHIELD ALCOHOL

AC INVERTER NO. 1

ANGLE-OF-ATTACKANGLE-OF-ATTACK HEATER

ANTI-COLLISION LIGHTBATTERY TEMPERATURE

CABIN DEFOG FAN & CABIN FANCABIN TEMPERATURE CONTROL

COCKPIT VOICE RECORDEREL PANEL LIGHTS

ENGINE SYNCHRONIZATIONFLAP CONTROL

FLAP MOTORFLIGHT RECORDER

GEAR CONTROLLANDING GEAR WARNING

LH BUS NO. 1,2,3LH CLOCKLH ENGINE ANTI-ICE

LH FAN SPEEDLH FUEL FLOW

LH FUEL QUANTITYLH ITT

LH OIL PRESSURELH OIL TEMPERATURE

LH PANEL LIGHTS

LH PITOT/STATIC (ANTI-ICING)LH START

LH THRUST REVERSERLH TURBINE SPEED

NAVIGATION LIGHTSNORMAL PRESSURIZATION

NOSEWHEEL RPMOUTSIDE AIR TEMPERATURE

PITCH TRIMRH BOOST PUMP

RH CB PANELRH FIRE DETECT

RH FIREWALL SHUTOFFRH IGNITION

ROTATING BEACONSKID CONTROLSPEEDBRAKE

STANDBY GYRO HORIZONTRUE AIRSPEED HEATER

WARNING LIGHT 1WINDSHIELD BLEED AIR

WINDSHIELD BLEED AIR TEMPWING INSPECTION LIGHT

ADI 2 (SINGLE EFIS)

AUDIO PANEL 1AUDIO PANEL 2

COMM 1

DIRECTIONAL GYRO 2

FLOOD LIGHTSNAV 2RH COPILOTPITOT/STATIC (682+)

EMERGENCY BUS (28V DC)

HOT BATTERY BUS


LH LANDING LIGHTLH REC LIGHTLH START LIGHTLH VOLTMETEROXYGEN/SEAT BELTTAIL LIGHT

RH REC LIGHTRH START LIGHTRH VOLTMETERRH WING INSP LIGHTTOILET/SHAVER

4

2

1

3

5

6

LH PRESS BLKHD CBs

L WING ANTI-ICE (5)

RH PRESS BLKHD CBs

R WING ANTI-ICE (5)

4B-5

7/28/2019 06 Elect

6/20


7/28/2019 06 Elect

7/20

Electrical System


DC Electrical SystemSII

4B-7

RH CROSSOVER BUS


GROUNDPOWERRELAY

BATTERYRELAY

225A

75A75A

35A 35A

80A80A

LEFT CB PANEL

RIGHT CB PANEL

AFT J-BOX

BATT

EMER BUS

L GEN

RESET

OFF

LH CROSSOVER BUS

15AINVERTER 1

15AINVERTER 2


R GEN

RESET

OFF


24V


LH STARTRELAY

RH STARTRELAY

RHPOWERRELAY

LHPOWERRELAY

550 - 626

LHGEN

225A


32.5V

1200A28.0V1000A

10

20 30

40D.C.

VOLTS

0

100200

300

400

D.C. AMP

0

100200

300

400

D.C. AMP

28.5V400A

BATTERY BUS

HOT BATTERY BUS

GCU

RHGEN

GCU


GENOFF

LH RH

AC BUSES


EMERPWR

RELAY

BATT

EMER

OFF

ENGINE START

DISENGAGELH

STARTDISC


AFT/FWD COMPARTMENT LIGHTSBAREMER LIGHTENTERTAINMENT CENTERINDIRECT LIGHT SYSTEMLH AMMETER

LH ANNUNCIATORLH BOOST PUMPLH BUS SENSELH GENERATORLH LANDING LIGHTLH RECOGNITION LIGHT


CABIN LIGHTSEMER LOCATOR BEACONEMER POWERFLOOD COOLINGIGNITION POWERRH AMMETERRH ANNUNCIATOR

RH BATT VOLTAGERH BOOST PUMPRH BUS SENSERH GENERATORRH LANDING LIGHTRH RECOGNITION LIGHTRH START LIGHT

RH MAIN BUS EXTENSION

LH CROSSOVER BUS


RH CROSSOVER BUS EMERGENCY BUS (28V DC)

LH START LIGHTLH VOLTMETEROXYGEN/SEAT BELT LIGHTTAILLIGHTTAILPRESSURE PUMP

RH WING INSPLIGHTRH VOLTMETERTOILET/SHAVER

4

2

3

5

6

ANTI COLLISION LIGHTSANGLE-OF-ATTACK HEATERCABIN DEFOG FANCABIN TEMPCENTER PANEL LIGHTSDIGITAL CLOCK 2EMERGNECY PRESSFLIGHT HOUR METERICE DETECTICE FLUID SYSTEMLH BOOST PUMPLH THRUST REVERSERNOSE WHEEL RPMOVERSPEED WARN

RH ALT. VIBRATORRH ENGINE BLEED AIRRH FIRE DETECTRH F/W SHUTOFFRH IGNITIONRH TURN AND BANKRH PANEL LIGHTSRH PITOT STATICROTATING BEACONSKID CONTROLWARNING LIGHTS 2WING INSPECTION LIGHTW/S ALCOHOLW/S BLEED AIR

AC INVERTER NO. 1ANGLE-OF-ATTACKBATT TEMPDIGITAL CLOCK 1EL PANEL LIGHTSENGINE SYNCEQUIPMENT COOLFLAP CONTROLFREON A/CGEAR CONTROLLANDING GEAR WARNLH BUS 1,2,3LH ENGINE BLEED AIRLH FAN SPEEDLH ITTLH FIRE DETECTLH F/W SHUTOFFLH FUEL FLOWLH FUEL QTY

LH IGNITIONLH TURB SPEEDLH OIL TEMPLH OIL PRESSLH PANEL LIGHTSLH PITOT STATICLH STARTNAVIGATION LIGHTSNORMAL PRESSOUTSIDE AIR TEMPPITCH TRIMRH BOOST PUMPRH CB PANELRH THRUST REVERSERSPEEDBRAKESTDBY GYROWARNING LIGHTS 1W/S BLEED AIR TEMP

COMM 1DG 2FLOOD LIGHTSNAV 2

ADF 1AUDIO 1AUTOPILOTDIRECTIONAL GYRO 1DME 1EADIEFISEFIS DISPEHSI

FD 1NAV 1RADARRADIO ALTIMETERRMI 1PHONETRANSPONDER 1VOICE ADV

AC INVERTER NO. 2ADF 2AREANAVAUDIO 2COMM 2COMM 3DME 2FD 2FMSGROUND PROX WARNLH CB PANELNAV DATABANKRH BUS NO. 1,2,3

RH FAN SPEEDRH FUEL FLOWRH FUEL QUANTITYRH ITTRH OIL PRESSURERH OIL TEMPERATURERH STARTRH TURBINE SPEEDRMI 2TAS HEATERTRANSPONDER 2VLF NAV

ADI 1ADI 2AIR DATAAPEFISFD 1FD 2GPWSHSI 1

HSI 2NAV 1NAV 2RADARRMI/ADF 1RMI/ADF 2V GYRO 1V GYRO 2

HOT BATTERY BUS


1

LHGEN

RHGEN

BATT

VOLTAGE SEL

ENGINE START

DISENGAGE RH

STARTDISC

2

4 5

6

3

1

7/28/2019 06 Elect

8/20


7/28/2019 06 Elect

9/20

Electrical System

Citation I/II/SII For training only 4B-9June 1997

DC SystemAircraft electrical system power sources include:

I one 24V DC nickel-cadmium battery

I two engine-driven generators

I external power system.

Nine buses distribute power from the various DC power sources:Hot Battery, Battery, Emergency, Left and Right Main, Left andRight Main Bus Extension, and Left and Right Crossover.

BatteryDepending on the aircraft, battery capacity varies from a 39 amp-hour (AH) unit in the Citation to a 44AH unit in the late modelCitation II.

With the battery switch in BATT, the battery relay closes to sup-

ply power from the Hot Battery bus to the Battery bus. From theBattery bus, power flows to the Left and Right Main buses. TheLeft and Right Main buses, in turn, power their Main BusExtensions and Crossover buses.

The emergency battery relay also closes to supply Hot Batterybus power to the Emergency bus. Connecting a ground powerunit with the switch in BATT allows external power to supply the

Hot Battery, Battery, and Main buses (see External Power).Placing the switch in the OFF position opens the relays; only theHot Battery bus receives power. On Citation II units 627 andsubsequent, if a generator is operating, power flows from thegenerator to the Battery bus and then to the Emergency busthrough the emergency power relay.

Selecting the EMER position opens the battery relay and closes

the emergency battery relay. Power flows from the Hot Batterybus to the Emergency bus only. The Battery and Main buses areunpowered.

7/28/2019 06 Elect

10/20


On Citation units 275 and subsequent, Citation II, andCitation SII, the battery disconnect relay automatically opens

during a ground power unit start to remove the battery from theelectrical system and avoid cycling of the battery. The relay clos-es automatically at the end of the start cycle.

If battery temperature exceeds 145F (63C), a temperature sen-sor in the battery case illuminates the BATT OHEAT/OTEMPannunciator steadily; above 160F (71C), the annunciator flash-es. An optional battery temperature gage provides continuous

indication of battery temperature.

Starter/GeneratorsTwo 30V DC, 400A or 300A (SII only) engine-driven starter/gen-erators are the primary source of DC electrical power. Duringengine starting they function as starters. At the end of the startcycle, the generator control units (GCUs) enable the transition

from starter to generator.Each GCU provides:

I field weakening during engine start

I automatic starter shutoff

I voltage regulation at 28.5V DC

I generator load sharing (paralleling)

I overvoltage and ground fault protection.

With the generator switch in GEN, regulation, protection, andMain bus connection are automatic. When generator output iscorrect, the power relay closes to connect the generator to itsMain bus. The Main buses, in turn, cross-tie through the Batterybus so that if one generator fails, the operating generator con-tinues to power the entire electrical system.

7/28/2019 06 Elect

11/20

Electrical System


If an overvoltage or feeder fault (short) occurs, the GCU opensthe generator field relay to de-energize the generator and the

power relay to disconnect the generator from its Main bus. Theassociated GEN OFF annunciator illuminates. Placing the gen-erator switch in OFF also opens the power relay to disconnectthe generator from its Main bus.

Momentarily holding the switch in RESET resets a generatorfield relay tripped from overvoltage, feeder fault, or when theENG FIRE switch is pushed. Selecting RESET may also be

necessary following a windmilling airstart.

External PowerWith an appropriately rated GPU connected, external powersupplies the Hot Battery bus through the closed external powerrelay. With the battery switch in BATT, the Hot Battery bus sup-plies power to the Battery bus and Left and Right Main buses

and the rest of the electrical system.When a generator comes on-line and begins supplying powerto the DC buses, the external power relay opens to disconnectexternal power.

An external power overvoltage/overcurrent sensor (exceptCitation units 001 to 274) protects the aircraft electrical sys-tem from overvoltage and overcurrent conditions. If GPU volt-

age exceeds 32.5V DC or current exceeds 1,200A, the sensoropens the external power disable relays to disconnect externalpower. Before external power can be reapplied, the overvolt-age/overcurrent sensor must be reset by disconnecting theGPU from the aircraft.

7/28/2019 06 Elect

12/20


AC Electrical SystemCitation 001 to 274

RH MAIN BUS EXT

X OVER

NORM

NO. 1

OFF

NO. 2

OFF

FLT DIR AC BUS

CB 70 COMPASSVERT GYROAP/FD CONTROL

RMI 2RMI 1ADIHSI

RADAR AC BUS

VOLTAGE

SENSOR(AP/FD BUS) RAD AC

PWR FAIL

F/D AC

PWR FAILVOLTAGE

SENSOR(RADAR BUS)

30A 30A3A AP/FD ANDA/C FAIL CB

(115V AC) (26V AC)

INVERTER2

INVERTER1

RADAR (115V AC)RADAR STAB (26V AC)OPTIONAL BENDIXRADIO ALTIMETER

LH MAIN BUS EXT

7/28/2019 06 Elect

13/20

Electrical System


AC System

Two static inverters convert 28V DC into 115V AC, 400 Hzthree-phase power and 26V AC, 400 Hz, single-phase powerfor avionic equipment and other equipment requiring AC power.Inverter rating varies from 300VA to 750VA with aircraft model,unit number, and customer preference.

Three distinct AC distribution systems are employed:

I dual inverters with separate flight director and radar AC buses

system (Citation units 001 to 274 only)I dual inverters with 115V and 26V AC buses (single bus

system)

I dual inverters with split bus system.

Early Model Citations (Units 001 to 274)With the inverter crossover switch in the NORM position and

the inverter switches on, the No. 1 inverter supplies the flightdirector AC bus and the No. 2 inverter supplies the radar ACbus. If an inverter fails, placing the crossover switch in X OVERenergizes relays to connect the No. 1 inverter to the radar busand No. 2 inverter to the flight director bus. A voltage sensor foreach AC bus illuminates its respective F/D AC PWR FAIL orRAD AC PWR FAIL annunciator when a bus loses power.

7/28/2019 06 Elect

14/20

4B-14 For training only Citation I/II/SIIMay 1998

AC Electrical SystemSingle Bus

LH MAIN EXT BUS

INVERTER2

VOLTAGESENSOR

ACFAIL

3A AC WARNING ORAC SWITCH

AC BUS

3A20A20AAC WARNINGOR

AC SWITCH

INVERTER1

A/C MONITORAIR DATA COMPUTERAUTOPILOTFD 1FD2 (OPTIONAL)VERTICAL GYRO 1VERTICAL GYRO 2 (OPTIONAL)

ADF 1ADF 2ADI 1HSI 1

INV 1

INV 2

O

FF

115V AC 26V AC

RMI 1RMI 2

RH MAIN EXT BUS

7/28/2019 06 Elect

15/20

Electrical System


Single-Bus SystemWith DC power available, placing the inverter control switch in

the INV 1 position turns the No. 1 inverter on. The inverter oper-ates to supply 115V and 26V AC to the AC buses. If the No. 1inverter fails, the AC FAIL annunciator illuminates and the buseslose power.

Placing the control switch in the INV 2 position turns the No. 2inverter on and energizes switching relays. The relays close androute No. 2 inverter output to the AC buses. The AC FAIL annun-

ciator extinguishes.

If 115V AC bus voltage is less than 90 5V or exceeds 125 5V,the voltage sensor illuminates the AC FAIL annunciator.

7/28/2019 06 Elect

16/20


AC Electrical SystemSplit Bus (CII 550 and subsequent; SII)

ACFAIL

INVERTERFAIL

INV 1

INV 2

TEST

AC

OFF

115V400Hz

26V400Hz

115V400Hz

26V400Hz

28V DC 28V DC

26V AC #1 26V AC #2 115V AC #2

1 2

ADCAUTOPILOTFD 1RADARVG 1

EFIS 1 (OPT)NAV 1RMI / ADF 1HSI 1ADI 1

FD 2 (OPT)VG 2

AC FAIL(ALLOWRESET)

AC FAIL(HOLD)

AC INVNO. 1

AC INV

NO. 2

INVERTER2

INVERTER1

LH MAIN BUS EXT RH MAIN BUS EXT

MASTERWARNING

RESET

115V AC #1

HSI 2NAV 2RMI / ADF 2ADI 2

ACFAIL

MASTERWARNING

RESET

CII 176 AND SUBSEQUENT WITH OPTIONAL DUAL

FLIGHT DIRECTORS

1

1

1

INVERTER1 FAIL

INVERTER2 FAIL

7/28/2019 06 Elect

17/20

Electrical System


Split-Bus SystemWith DC power available and the inverter control switch in the

AC position, 28V DC from the DC buses powers the No. 1 andNo. 2 inverters. The inverters supply 115V and 26V AC to theirrespective buses.

If an inverter fails, its switching relays relax to connect the oper-ating inverter to the failed inverters buses. The associated INVFAIL annunciator illuminates. The AC FAIL annunciator also illu-minates and triggers the MASTER WARNING lights. Resetting

the MASTER WARNING lights extinguishes the AC FAILannunciator.

The inverter test switch allows preflight testing of the inverterswitching system. Placing the switch in the INV 1 or INV 2 posi-tion simulates an inverter failure by cuttings its DC input. Theinverter loses power, the INV FAIL and AC FAIL annunciatorsilluminate, the Master Warning lights flash, and the affected

inverters switching relays relax to connect the operating invert-er output to the failed inverters buses.

7/28/2019 06 Elect

18/20


Electrical System

Power Source Battery 24V DC, 39 to 44AH(2) Starter/generators 30V DC

(28.5V regulated)400A max load (Citation I/II)300A max load (Citation SII)

GPU (28V DC, 800 to 1000A)(2) Inverters 115V AC, 400 Hz and 26VAC, 400 Hz (inverter rating varies with A/C)

Distribution DC DistributionHot Battery busBattery busEmergency busLH/RH Main DC busesLH/RH Main Bus ExtensionsLH/RH Crossover buses

AC DistributionCitation 001 to 274

Flight Director and Radar AC busesSingle bus systems

115V AC and 26V AC busesSplit bus systems

No. 1 115V AC and 26V AC busesNo. 2 115V AC and 26V AC buses

7/28/2019 06 Elect

19/20

Electrical System


Electrical System (cont.)

Control DC systemBATT switchL/R GEN switches

AC systemCitation 001 to 274

No. 1/No. 2 inverter switchesX OVER/NORM switch

Single bus system

INV 1/OFF/INV 2 switchSplit bus systemAvionic PowerAC/OFF switchDC PWR to invertersINV 1/TEST/INV 2 switch

Monitor Annunciators

L/R GEN OFFBATT OHEAT/BATT OTEMPAC FAILF/D AC PWR FAIL & RAD AC PWR FAILINVERTER 1/2 FAIL

AmmetersVoltmeterBattery temperature gage (if installed)Master warning

Protection Circuit breakersCurrent limitersGenerator control units (CGUs)External power overvoltage/

overcurrent sensor

7/28/2019 06 Elect

20/20

4B-20 For training only Citation I/II/SII

06 elect

Documents