Electrical System Upgrade Ground Training

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Electrical System Upgrade Ground Training

• TCTO 1C-130-1339

OPR HQ AMC/DOTA 15 APRIL 1999
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ESU Ground Training Overview

• Why is an upgrade needed ?
• Overview of Modification
• ESU Components
• Changes to Normal Procedures
• Changes to Emergency Procedures
• Aircraft Visit

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Why is an upgrade needed?

• HISTORY
• Earlier C-130s equipped with analog electrical
  equipment
• Newer generation avionics equipment, requires
  improved power regulation
• PURPOSE
• ESU will provide cleaner, steady-state power to
  aircraft electrical components/systems.

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Overview of Modification

• Replaces Generator Control Panel with Generator
  Control Units (one for each engine driven
  generator and APU, Not ATM generator)
• Adds 2 New AC Buses
• Each New AC Bus Is Powered Through Their Own Bus
  Switching System (BSS)
• BSS provides clean regulated power and offers
  an immediately available secondary power source
  for its respective bus

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ESU Components

• 4/5 Generator Control Units, 4/5 Generator
  Control Switches
• 2 AC buses (ESSENTIAL Avionics MAIN Avionics)
• 2 Bus Switching Systems (BSS)
• 2 Fail-Safe Bypass Contactors (FBC)
• 2 AC Bus Warning Lights, 3 ESU Advisory Lights
• 2 Solid State Inverters (2,500 250 KVA)

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General Location of ESU Components
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4 or 5 Generator Control Units (GCU)

• Mounted on the electrical control and supply rack
• Takes place of the Voltage Regulator, Generator
  Control Panel, and Frequency Sensitive Relay
• Controls the contactors that tie the generators
  to the buses
• Provides protection from over/under voltage,
  over/under frequency, and feeder faults by
  deenergizing the appropriate contactor

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4 or 5 Generator Control Units (GCU)
Test Button
Circular Connector

• Two Major
• Features of the
• GCU
• BIT (Built-In Test)
• Engine Generator
• Switches

Bit Display Panel
TOP VIEW
Truth Table
Perforated Surface
FRONT VIEW
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Built In Test of the GCU

• Push button on GCU initiates test
• Can be run anytime ISOL DC is available and
  generator switches are ON (does not have to be
  on-line)
• LED indicators light for 10 Seconds then
  extinguish (if good)
• Template decodes LED indication (Truth Table)
• GCU does its own BIT prior to connecting
  generator to a bus

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Built In Test of the GCU

• If the GCU trips in flight an LED code will be
  displayed on the GCU. The Truth Table shows the
  meaning.
• RESET Generator OFF, Generator ON (Recheck
  Output)
• The GCU has a latching circuit that prevents a
  serious electrical problem from being RESET.

fig. p. 84
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LED TRUTH TABLE
NO FAULTS OVER VOLTAGE UNDER VOLTAGE UNDER
FREQUENCY OVER FREQUENCY FEEDER FAULT PREVIOUS
FEEDER FAULT CONTACTOR CURRENT LIMIT INCORRECT
GENERATOR SELECT GENERATOR SELECT TIME
OUT INTERUPT CAPACITY EXCEEDED PREVIOUS BIT
FAILURE DIGITAL BOARD FAILURE POWER BOARD
FAILURE CHASIS FAILURE BIT IN PROGRESS
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Generator Control Switches
NO. 1 ENGINE GENERATOR
NO. 1 ENGINE GENERATOR
OFF
FIELD TRIP
OFF
RESET
ESU
OLD
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Engine Generator Switches of the GCU

• Switches appear identical, except ESU have no
  RESET or FIELD TRIP positions (no need)
• Causes and Reactions of a GENERATOR OUT light
• Disconnects generator from bus (can be RESET) If
  any phase gt130VAC or lt95VAC (after 4 seconds of
  the under/over voltage)
• Temporarily disconnects generator from bus
  lt368HZ or gt440HZ
• Permanently disconnects generator from bus
  Feeder Fault (gt35amp difference between generator
  and contactor terminals)

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Main AC Bus
Secondary AC
BSS No. 2
Main AVI Bus
Copilots Upper CB Panel

• Radar
• SKE
• (other, see -1)

• C-12 Compass 1 2
• Autopilot
• INU (3 Phase)
• BICU (3 Phase)
• Radio Compass 36VAC
• (other, see -1)

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FBC
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(No Transcript)
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Bus Switching System (BSS) Components
10 KVA Inverter

• - Mounting Base
• Assembly
• - Rectifier Control
• Unit (RCU)
• - 10 KVA Inverter

Rectifier Control Unit (RCU)
Fans
Chassis Ground Stud
Input Secon. Power
Signal Interface
Output Power
Input Prim. Power
BSS (FRONT VIEW)
Bit Balls (Black - OK White - FAILURE
Base Assembly
BSS (rear view)
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Mounting Base Assembly - BSS

• Houses a Capacitive Discharge Bank
• Surge Protector for the 10 KVA Inverter
  (provides a minimum of 60 milliseconds of DC
  power, longer than normal switchover time)
• Serves as the power interface for the GCU
• WARNING
• Due to residual capacitance charge , it is
  necessary to allow 6 minutes after BSS shutdown
  prior to removing any part of the unit or its
  cannon plugs.

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Rectifier Control Unit (RCU)

• Provides 340 VDC (primary power source) or 270
  VDC (secondary power source) to the 10 KVA
  Inverter
• How?
• 340 VDC (primary power) Developed through AC to
  DC converter, then DC to DC booster to increase
  to 340 VDC
• 270 VDC (secondary power) Developed through AC
  to DC converter
• Why two sources?
• Any power spike/drop, or switch over anomalies
  that temporarily kick the primary power off line
  allows the secondary power to provide
  uninterrupted DC current flow

340VDC
340VDC
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10 KVA Inverter

• Inverts 340VDC (or 270 VDC) into Regulated 115V,
  400Hz AC pwr for the ESS and MAIN AVI buses
• Safety Features
• Input Power of lt 200 VDC causes the Inverter to
• Drop the output voltage to 0 to prevent
  equipment damage
• Shutdown and reset the Rectifier Control Unit
  circuits
• Remove the ground for the Fail-Safe Bypass
  Contactor
• An Input Power increase to gt220 VDC will restart
  the inverter

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Fail-Safe Bypass Contactor (FBC)

• A Fail-Safe backup for a BSS failure
• BSS failure causes the FBC to redirect power for
• ESS AVI Bus off the ESS AC Bus for a BSS 1
  failure
• MAIN AVI Bus off the MAIN AC Bus for BSS 2 failure

NOTE Time between power application to the BSS
and the FBC energizing to allow BSS output
connection to AVI is 2.5 - 5 seconds.
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2 Additional AC Bus Warning Lights,
BUS OUT INDICATORS

• ESS AVI (or MAIN AVI)
• Indicator Lights Anytime
• Average bus voltage lt 95VAC
• Single phase voltage lt 90VAC
• EFFECT NO POWER is
• available to that bus, FOLLOW
• Bus Isolation Procedures

ISO DC ON BATT
ESS DC OFF
MAIN DC OFF
RH AC OFF
LH AC OFF
MAIN AC OFF
ESU BIT
ESS AVI
ESS AC OFF
ESS
MAIN
MAIN AVI
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3 ESU Advisory Lights

• ESU BIT Indicator
• Lights anytime a fault occurs within the BSS 1 or
  BSS 2
• EFFECT Affected BSS may be on Primary only or
  Secondary Power -- NO ABORT, Record in 781
• ESS Indicator (MAIN Indicator)
• Lights anytime a fault within BSS 1 (BSS 2)
  causes the Fail-Safe Bypass Contactor to
  deenergize
• EFFECT Affected Bus is on dirty power, no
  more clean power from BSS

BUS OUT INDICATORS
ISO DC ON BATT
ESS DC OFF
MAIN DC OFF
RH AC OFF
LH AC OFF
MAIN AC OFF
ESU BIT
ESS AVI
ESS AC OFF
ESS
MAIN
MAIN AVI
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250 VA and 2500 VA Solid State Inverters

• Replaces the old rotary 250VA and 2500VA
  Inverters (for the Secondary AC Power Supply,
  CoPilots AC Instrument and AC Instrument
  Engine Fuel Control Bus)
• Provides a cleaner, better regulated power source
  for these buses
• NO Change in operations or restrictions

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Changes to Normal Procedures

• Before Exterior Inspection (Cargo Compartment)
• BSS Circuit Breaker Panel (FS-245) - Checked
  (Ensure power is off before resetting circuit
  breakers)
• Power On Inspection
• Generator Switches - Set, as required
• (ON for ESU Aircraft, OFF for non-ESU
  Aircraft)
• Cockpit Checklist
• Electrical Panel (ESU Aircraft) - Set
• Engine Generator Switches - ON

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Changes to Normal Procedures

• Starting Engines Checklist
• (Procedures modified to include ESU Aircraft)
  Check for voltage output on all 3 Phases After
  engine is on speed.
• Taxi Checklist
• Generators and Loads - Checked (ESU Aircraft
  should have normal indications if the generator
  is not OUT)
• Engine Shutdown Checklist
• Leave Generator Switches ON, for ESU Aircraft

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Changes to Emergency Procedures

• 4 Engine Power Loss
• Step 5. (Turning off the generator supplying
  Essential AC Bus) Not applicable for ESU Aircraft
• Electrical System Failure
• A malfunction to the LH, RH, or Main AC bus (or
  Main AVI Bus for ESU Aircraft) or its equipment
  may require turning off all 4 Engine Generators
  to isolate problem
• Generator Out Light on ESU Aircraft (New GCU)
• Frequency and Voltage Normal, No Load - Leave
  Generator On and Monitor
• No Frequency, Voltage, or Load - Place
  Generator Switch Off, then On, Recheck
  Indications, If Still Bad -- Generator Disconnect

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Changes to Emergency Procedures

• AC Bus Off Light
• ESU follow procedures for Airplanes with ESU
• If Affected Gen Out Light is ON, turn Gen OFF and
  Disconnect
• If Affected Gen Out Light is NOT On, Check
  Voltage, Frequency, and Load -- if all good,
  Continue Ops Monitor
• If Affected Gen Out Light is NOT On, but
  Equipment is Malfunctioning -- follow Bus
  Isolation Procedures.
• Loss of ESS AC Bus (on ESU Aircraft)
• Will NOT Affect ESS AVI or Main AVI Buses
  (Normally)
• ESS AVI affected if FBC is de-energized (Dirty
  Power)

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Changes to Emergency Procedures
Illumination of an AVI Bus Off Light (ESU
AIRCRAFT)
No, Continue Ops and Monitor
Equip. Malfunctioning ?
If Yes
Check CBs, reduce load and reset CBs Is power
restored with reduced load?
Yes, Continue Ops and Monitor
If No
Isolate AVI bus
If the problem occurred on the ESS AVI Bus -
Regardless of apparent success, Land As Soon As
Possible
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Changes to Emergency Procedures

• Electrical Isolation Procedures for ESU Aircraft
• Transitioning from BSS regulated power to Power
  Directly from the ESS/Main AC bus
• ESS AVI/Main AVI Pull ISOL DC BUS AVIONICS
  ESS/MAIN FBC CONTROL Circuit Breaker (located
  on Pilots Side CB Panel)
• Isolating/Removing the BSS 1 (BSS 2)
• Pull the 2 sets of 3 ganged Circuit Breakers on
  the aft side of Flight Station 245
• ESS / MAIN AVI SECONDARY POWER
• ESS / MAIN AVI PRIMARY POWER

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Changes to Emergency Procedures

• Electrical Isolation Procedures for ESU Aircraft
• Isolating/Removing Power from an AVI Bus
• ESS AVI Pull the 3 ESS AVI AC BUS POWER Circuit
  Breakers (Pilots Upper CB Panel)
• WARNING Prior to pulling ESS AVI power, ensure
  P/CP FDMS panel vertical reference switch is in
  VG position
• CAUTION Prior to pulling ESS AVI power, place
  CPs Secondary AC Inverter Switch to DC position
• Main AVI Pull the 3 MAIN AVI AC BUS POWER
  Circuit Breakers (Copilots Upper CB Panel)

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ESU Ground Training Review

• Why is an upgrade needed ?
• Overview of Modification
• ESU Components
• Changes to Normal Procedures
• Changes to Emergency Procedures
• Aircraft Visit

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QUESTIONS?