Buses
  • Hot Battery Bus
  • Left Main Bus
  • Right Main Bus
  • Crossfeed Bus
  • Left Feed Extension Bus
  • Right Feed Extension Bus
  • Left Crossover Bus
  • Right Crossover Bus
  • 2 Emergency Buses
CJ1 & CJ Hot Battery Bus Items
  • Emergency Exit Lights
  • Tailcone Compartment Lights
  • Baggage Compartment Lights
  • Passenger Advisory Lights
  • Voltmeter (inop if Battery switch is off)
  • Ignition Power
  • ELT (optional)
  • Emergency Battery Pack
CJ1 Emergency Bus Items
  • Comm 1
  • Nav 1 and Marker Beacon
  • Right Pitot Static System
  • Pilot's Omni Bearing Selector (OBS)
  • Pilot Airspeed
  • Pilot's Altitude Encoder
  • Both Audio Amplifiers
  • Overhead Floodlights
  • Copilot's DG
  • Fan Speed (N1)
  • Voltmeter
  • Landing Gear Warning
  • Landing Gear Control
  • Flap Control
  • AHRS #2

  • Standby Gyro (has it's own battery pack, not on the emergency bus)
CJ Emergency Bus Items
  • Comm 1
  • Nav 1 and Marker Beacon
  • Left Hand Pilot-Static Heat System
  • Pilot's Omni Bearing Selector (OBS)
  • Pilot's RMI
  • Pilot's Altitude Encoder/Vibrator
  • Both Audio Amplifiers
  • Overhead Floodlights
  • Copilot's DG
  • Fan Speed (N1)
  • Voltmeter
  • Standby Gyro
Battery
  • 24 vdc/28 amp-hour NICAD (based on a 5 hour discharge period)
  • Optional 24 vdc / 44 ampere-hour battery available
  • Located in tailcone
  • Check level only when fully charged
  • Limitation: 24 volts minimum
  • Battery Start Limitation: Three starts within 1 hour, a cross-generator start equals 1/3 of a battery start
Battery Switch Positions
  • Battery
    • Battery relay closed
    • Emergency relay closed to crossfeed but
    • All buses powered by battery, APU or S-G
  • Emergency
    • Battery relay open
    • Emergency relay closed to hot battery bus
    • Only emergency and hot battery buses
    • powered by battery or APU (others by S-G)
  • Off
    • Battery relay open
    • Emergency relay closed to crossfeed bus
    • Only hot battery bus is powered by battery
    • or APU (Others by S-G)
Starter-Generators
  • 30 vdc rated/ 29 vdc regulated
  • 300 amp
  • Accessory gearbox driven
  • Loadsharing between generators +/- 30 amps
  • Air-cooled on the ground by an internal fan, ram air cooled in flight
  • 50% overload to 450 amps for 2 minutes max
  • 1500 in-lb shear section
  • Left Starter-Generator (SG) powers left main bus
  • Right Starter-Generator powers right main bus
  • Crossfeed/Battery bus acts as a crosstie through two 225 amp current limiters
  • Limitation: 300 Amps
  • Starter Limitation: Three starts in 30 minutes, with a 30 second rest between each start
Generator Control Units ( One for each generator )
1. GCU Functions:
  • Starter Cuttoff:
    At 45% N2, an integral tach-generator speed sensor circuitry will discontinue starting and begin power generation
  • Field Relay (FR) Reset from a Dead Bus:
    if VM reads Zero, the FR is open, can be reset by placing the Gen switch to "Reset". (If VM reads normal, Power Relay is open, & reset is not possible)
  • Voltage Regulation: To 29 vdc max
  • Paralleling/Load Divison:
    To +/-30 amps max deviation from equal load between SGs
  • Overvoltage/Overexcitation Protection: at 32.5 vdc
  • Feeder Fault/Ground Fault Protection:
    150-200 amp max allowable load top fault
  • Reverse Current/Differential Voltage
    Removes generator off-line with reversal of 10% of its load rating or more
  • Field Weakening:
    Reduces current drain to prevent damage to starter brushes during starter acceleration
External Power Cart
  • 29 vdc
  • Maximum output of 1000 amps
  • Maximum output of 600 amps, or 800 amps if above 5,500 MSL
  • Disengage generators before connecting external power
Volts and Amps
SYSTEM CONTROLS
SYSTEM RESET
OPERATION HINTS

Hints for Engine start

  • Batt-on
  • l gen-on
  • r gen-on
  • l start-push
  • r start-push
Engine Start
SYSTEM CONTROLS
SYSTEM RESET
OPERATION HINTS

Hints for AFT j-box cb-

  • aft j box annun-press
  • l engine start button-press
Aft J-Box CB
SYSTEM CONTROLS
SYSTEM RESET
OPERATION HINTS

Hints for AFT j-box lmt

  • aft j box lmt annun-press
Aft J-Box Lmt
SYSTEM CONTROLS
SYSTEM RESET
OPERATION HINTS

Hints for batt disable relay on start

  • l gen start button-press
Batt Diable Relay On Start
SYSTEM CONTROLS
SYSTEM RESET
OPERATION HINTS

Hints for batt otemp batt emer no effect-

  • battery o'temp annum-press
  • battery switch-emer
  • battery switch-on
  • battery disconnect sw-open
  • battery disconnect sw-disc
Batt O'Temp - No Effect
SYSTEM CONTROLS
SYSTEM RESET
OPERATION HINTS

Hints for batt otemp

  • battery o'temp annum-press
  • battery switch-emer
Batt O'Temp
SYSTEM CONTROLS
SYSTEM RESET
OPERATION HINTS

Hints for dual gen fail-

  • gen annum-press
  • r gen-reset
  • l gen-reset
  • voltage knob-r gen
  • voltage knob-l gen
  • l gen-gen
  • r gen-gen
Dual Generator Failure
SYSTEM CONTROLS
SYSTEM RESET
OPERATION HINTS

Hints for power relay open good gen-

  • generator annum-press
  • master caution-press
  • voltage sel knob-l gen
  • l gen sw-off
Power Relay Open
SYSTEM CONTROLS
SYSTEM RESET
OPERATION HINTS

Hints for power relay open tripeed gen with reset -

  • gen off annum-press
  • voltage sel knob-l gen
  • l gen switch-reset
  • voltage sel knob-l gen
  • voltage sel knob-r gen
  • l gen switch-l gen
Power Relay Open Tripeed
CJ1 Panel
CJ Panel