C550GT ICA v.8 11-09-2020 copy

MAINTENANCE MANUAL SUPPLEMENT 12-20-06- Instrument Panel
C550GT-AD016-FU24-0213
Instrument Panel Revision: Initial Issue DATE: 01/01/2020

Instrument Panel Maintenance Practices / Servicing
Servicing

Instrument Panels

1. Anti-vibration Mount Inspection.

For Removal, Installation and Inspection of Instrument Panel Isolation mounts refer to Chp. 39 of this ICA.
See Chp. 39 Inspection of Centre Panel Isolation Mounts.

Page 314

MAINTENANCE MANUAL SUPPLEMENT 12-30-01- Electrical Power
C550GT-AD016-FU24-0213
Electrical Power Revision: Initial Issue DATE: 01/01/2020

Electrical Power Maintenance Practices / Servicing
Servicing
12-30-00 Unscheduled
Electrical Power

1. Battery Charging

Ref. Ext. Doc: Teledyne Battery Products (Doc. No. Q01-1101) Component Maintenance Manual, LT Valve-Regu-
lated lead-Acid Batteries.

2. Battery Capacity test

Ref. Ext. Doc: Teledyne Battery Products (Doc. No. Q01-1101) Component Maintenance Manual, LT Valve-Regu-
lated lead-Acid Batteries.

Page 315

MAINTENANCE MANUAL SUPPLEMENT 12-30-02- Landing Gear Shock Struts
C550GT-AD016-FU24-0213
Landing Gear Shock Struts Revision: Initial Issue DATE: 01/01/2020

Landing Gear Shock Struts Maintenance Practices / Servicing
Servicing

1. MLG Strut Servicing.
(1) Lift the aircraft until the wheels are clear of the ground. Single or Double lift. See Chp. 07 Lifting and
Shoring.

WARNING: BEFORE YOU DO ANY WORK ON THE LANDING GEAR LEG, DEFLATE THE SHOCK STRUT
PRESSURE. THE VERY HIGH PRESSURE INSIDE THE STRUT CAN CAUSE INJURY OR DEATH.

(2) Remove the charge valve cap.
(3) Remove the charge valve core.
(4) Put a length of plastic tubing over the threaded portion of the valve and put the free end into a container.
(5) Carefully loosen the charge valve lock nut to slowly release the pressure.
(6) Note: A small quantity of oil will release with the nitrogen pressure.
(7) Set the length of the exposed piston to 4 inches.

NOTE: Accurately measure this distance or use a spacer between the piston socket and the lug.
(8) Fill the cylinder with MIL-H-5606G fluid. (or equivalent)
(9) Install a new seal onto the charge valve and install the valve core.
(10) Install the charge valve and safety it with lockwire.
(11) Connect the Strut Service Adapter AERO Product ID: 2002763 (or equivalent)

NOTE: This type of adapter correctly opens the valve core.
(12) Use DRY NITROGEN to slowly pressurise the shock strut to 350-450 psi.
(13) Tighten the charge valve lock nut.
(14) Install the charge valve cap.

CAUTION: BEFORE YOU LOWER THE JACKS, MAKE SURE ALL THE TRESTLES AND SUPPORTS, INCLUDING
THE ADJUSTABLE TAIL SUPPORT ARE CLEAR OF THE AIRCRAFT.

(15) Lower the aircraft slowly until all weight is off the jacks.
(16) Remove the jacks from under the aircraft.

2. NLG Strut Servicing.

(1) Lift the aircraft until the nosewheel is clear of the ground. Double lift. See Chp. 07 Lifting and Shoring.

WARNING: BEFORE YOU DO ANY WORK ON THE LANDING GEAR LEG, DEFLATE THE SHOCK STRUT
PRESSURE. THE VERY HIGH PRESSURE INSIDE THE STRUT CAN CAUSE INJURY OR DEATH.

(2) Remove the charge valve cap.
(3) Remove the charge valve core.
(4) Put a length of plastic tubing over the threaded portion of the valve and put the free end into a container.
(5) Carefully loosen the charge valve lock nut to slowly release the pressure.

NOTE: A small quantity of oil will release with the nitrogen pressure.
(6) Set the length of exposed piston to 5 inches.

NOTE: Accurately measure this distance or use a spacer between the piston socket and the lug.
(7) Fill the cylinder with MIL-H-5606G fluid. (or equivalent)
(8) Install a new seal onto the charge valve and install the valve core.
(9) Install the charge valve and safety it with lockwire.
(10) Connect the Strut Service Adapter AERO Product ID: 2002763 (or equivalent)

NOTE: This type of adapter correctly opens the valve core.

Page 316

MAINTENANCE MANUAL SUPPLEMENT 12-30-02-Landing Gear Shock Struts
C550GT-AD016-FU24-0213
Landing Gear Shock Struts Revision: Initial Issue DATE: 01/01/2020

Maintenance Practices / Servicing

(11) Use DRY NITROGEN to slowly pressurise the shock strut to 160-200 psi.
(12) Tighten the charge valve lock nut.

CAUTION: BEFORE YOU LOWER THE JACKS, MAKE SURE ALL THE TRESTLES AND SUPPORTS, INCLUDING
THE ADJUSTABLE TAIL SUPPORT ARE CLEAR OF THE AIRCRAFT

(13) Lower the aircraft slowly until all weight is off the jacks.
(14) Remove the jacks from under the aircraft.
(15) Remove the adjustable tail support from the tail skid.

Page 317

MAINTENANCE MANUAL SUPPLEMENT 12-30-03- Propeller Lubrication
C550GT-AD016-FU24-0213
Propeller Lubrication Revision: Initial Issue DATE: 01/01/2020

Propeller Lubrication Maintenance Practices / Servicing
Servicing

Propeller Lubrication

Refer to Chapter 61 - Propeller for information about Scheduled and Unscheduled maintenance and lubrication of
the Hartzell Propeller HC-B3TN-3D installed on the Crusader 550GT. See Chp. 61 Servicing.

Page 318

MAINTENANCE MANUAL SUPPLEMENT 20-00-00 - Standard Practices
C550GT-AD016-FU24-0213
Chapter 20 Revision: Initial Issue DATE: 01/01/2020

Title Page Standard Practices

Chapter 20
Standard Practices

Chapter 20 Standard Practices

Title Page

MAINTENANCE MANUAL SUPPLEMENT 20-00-00 - Chapter Guide DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide
MANUAL TO USE
Chapter Guide
Manual to Use N/A FU24- 954 C550GT

Applicable Section Guide 
SECTION / SUB-SECTION 

20-00-00 Standard Practices
Standard Practices
Standard Torques
Fuel Conversion Table

Page i

MAINTENANCE MANUAL SUPPLEMENT 20-00-00 - General DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue General
Standard Practices
20-00-00 General
Standard Practices
General

Standard Practices

Standard Practices info to be added as required.

MAINTENANCE MANUAL SUPPLEMENT 20-00-02- Standard Torques
C550GT-AD016-FU24-0213 Revision: Initial Issue DATE: 21/21/2121
Standard Torques Maintenance Practices / Standard Practices

Standard Torques
Standard Practices

Standard Torque Chart

Table 20(a) Standard Fastener Torques

Page 2

MAINTENANCE MANUAL SUPPLEMENT 20-00-03 - Conversion Table
C550GT-AD016-FU24-0213
Conversion Table Revision: Initial Issue DATE: 01/01/2020

Conversion Table Standard Practices
Standard Practices

Fuel Conversion Table.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 21-00-00 - Air Conditioning DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Air Conditioning
Chapter 21

Title Page

Chapter 21
Air Conditioning

Chapter 21 Air Conditioning

MAINTENANCE MANUAL SUPPLEMENT 21-00-00 - Air Conditioning DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Air Conditioning
Chapter Contents

Chapter Contents
Air Conditioning

Chapter Contents

Chapter 21 Air Conditioning

Applicable Section Guide
21-20-00 Fresh Air Distribution

Description and Operation
> Fresh Air Vent System

Components Changed By This STC

Maintenance Practices
Removal and Installation
> Fresh Air Vent valve duct.
Adjustment and Test
> Fresh Air Vent Control Rigging.
Inspection and Check
> Fresh Air Vent System

MAINTENANCE MANUAL SUPPLEMENT 21-00-00 - Manual to Use DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide
MANUAL TO USE
Chapter Guide
Manual to Use N/A FU24- 954 C550GT

Applicable Section Guide 
SECTION / SUB-SECTION

21-00-00 Air Conditioning 
21-20-00 Fresh Air System 
Description and Operation

Ventilation - Fresh Air
Maintenance Practices
Removal and Installation

Fresh Air Duct
Adjustment and Test

Fresh Air Control Rigging
Inspection and Check

Engine Fresh Air System

21-40-00 Heating X
Description and Operation

Cockpit Heating
Maintenance Practices
Removal and Installation

Adjustment and Test

Inspection and Check

21-50-00 Cooling X
Description and Operation

Radio Cooling
Maintenance Practices
Removal and Installation

Adjustment and Test

Inspection and Check

MAINTENANCE MANUAL SUPPLEMENT 21-20-00-Fresh Air System
C550GT-AD016-FU24-0213
Fresh Air System Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Air Conditioning

Fresh Air System
Air Conditioning

21-20-00 Fresh Air Distribution

Description and Operation

Fresh Air Vent System

A NACA air inlet in the bottom engine cowl extracts fresh air from forward of the LH engine exhaust for cabin
ventilation. Rectangular ducting, integral to the cowl, directs the fresh air rearward to a round duct connection.
Aeroduct SCAT® tubing connects to a firewall Fresh Air Vent valve.

The Fresh Air Vent assembly bolts to the firewall, on the LH side in the engine compartment. The Vent assembly
has a cable-controlled flap valve with a control handle positioned above the Centre Instrument Panel. Operating
the cockpit control actuates the valve which regulates air flow and shuts off the air.

On the cockpit side of the firewall just above the horizontal bulkhead, SCAT® ducts tee off from the Fresh Air
Valve. These ducts route air to the two Whisperflo® vents on the LH and RH Instrument Sub-Panels. Air flow is
able to be directed and regulated at these outlet vents.

Figure 21.1 Bottom Cowl Fresh Air duct.
Page 1

MAINTENANCE MANUAL SUPPLEMENT 21-20-00 - Components Changed Table
C550GT-AD016-FU24-0213
Components Changed Table Revision: Initial Issue DATE: 01/01/2020

Components Changed Table CCBTS / Air Conditioning
Air Conditioning

Components Changed By This STC

Drawing Number Item Part Number Description / Location
AD-550GT-2150-001-000
AD-550GT-2150-001-000 1 248380-1 Cable
AD-550GT-2150-001-000
AD-550GT-2150-001-000 2 AD-550GT-2150-001-001 Vent Bracket
AD-550GT-2150-001-000
AD-550GT-2150-001-000 3 AD-550GT-2150-001-002 Vent Cable Block
AD-550GT-2150-001-000
AD-550GT-2150-001-000 8 ASS-32 Hose Clamp

9 ASS-44 Hose Clamp

10 FC21-001 Fresh Air Vent

16 SCAT 8 Hose

17 SCAT 10 Hose

Page 2

MAINTENANCE MANUAL SUPPLEMENT 21-20-00- Fresh Air Duct
C550GT-AD016-FU24-0213
Fresh Air Duct Revision: Initial Issue DATE: 01/01/2020

Fresh Air Duct Maintenance Practices / Removal and Installation
Removal and Installation

Maintenance Practices
Removal and Installation

1. Fresh Air Vent valve duct.
Ref. Dwg. No: AD-550GT-2150-001-000
The Fresh Air SCAT duct must be removed before you remove the lower cowl.

(1) Disconnect the SCAT duct at the firewall Fresh Air Vent valve or at the cowl duct.

NOTE: If you remove the SCAT Duct (17) at the cowl, make sure you secure the loose end of the duct before
you ground run the engine.

(2) Install the scat duct when you refit the engine cowl.

Figure 21.2 Fresh Air Vent System.
Page 401

MAINTENANCE MANUAL SUPPLEMENT 21-20-00- Rigging
C550GT-AD016-FU24-0213
Rigging Revision: Initial Issue DATE: 01/01/2020

Rigging Maintenance Practices / Adjustment and Test
Adjustment and Test
Adjustment and Test
Fresh Air Vent Control Rigging.
Ref. Dwg. No: AD-550GT-2150-001-000

In the cockpit.

(1) Move the Fresh Air control through the full range. Make sure the cable is free and there is no binding.
(2) Set the control handle 1/8 in. out from the panel.

In the engine compartment.

(1) Disconnect the SCAT duct (17) so you can see the position of the valve flap in the Fresh Air Vent (10).
(2) Check that the valve flap is firmly closed.
(3) Adjust the cable (1) at the valve flap control lever to get this. (Detail A) See Figure 21.2
(4) In the cockpit, pull the Fresh Air Control handle fully out.
(5) Check that the valve flap is open and centered in the Fresh Air Vent housing.
(6) Adjust the cable (1) at the valve flap control lever to get this. (Detail A)
(7) Reconnect the SCAT duct.

Page 501

MAINTENANCE MANUAL SUPPLEMENT 21-20-00- Engine Bay Fresh Air System
C550GT-AD016-FU24-0213
Engine Bay Fresh Air System Revision: Initial Issue DATE: 01/01/2020

Engine Bay Fresh Air System Maintenance Practices / Inspection and Check
Inspection and Check

Inspection and Check

1. Fresh Air Vent System
Ref. Dwg. No: AD-550GT-2150-001-000
(1) Check that the cable control is free to move through the full range and there is no binding.
(2) Examine the seal between the firewall vent cable block (3) and the cable outer (1).
(3) Check the P-clamp that holds the cable outer is secure.
(4) Examine the engine compartment SCAT® ducting for condition and check that the clamps are secure.

WARNING: TOXIC FUMES CAN ENTER THE COCKPIT THROUGH DAMAGED DUCTING. MAKE SURE THE
DUCTING IN THE ENGINE COMPARTMENT IS IN GOOD CONDITION.

(5) Check the operation of the Whisperflo vents.

Figure 21.3 Fresh Air System - Firewall

Page 601

MAINTENANCE MANUAL SUPPLEMENT 23-00-00 - Communication DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Communication
Chapter 23

Title Page

Chapter 23
Communication

Chapter 23 Communication

MAINTENANCE MANUAL SUPPLEMENT 23-00-00 - Communications DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Communications
Chapter Content

Chapter Content
Communications

Chapter Contents

Chapter 23 Communication

Applicable Section Guide
23-10-00 Speech Communication

Description and Operation
> Garmin SL40 VHF Comm
> Troubleshooting
> Removal and Installation
> Adjustment and Test

23-50-00 Audio Integration
Description and Operation
> PMA 4000 Audio Panel
> Troubleshooting
> Removal and Installation
> Adjustment and Test

MAINTENANCE MANUAL SUPPLEMENT 23-00-00 - Manual to Use DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide
MANUAL TO USE
Chapter Guide
Manual to Use N/A FU24- 954 C550GT

Applicable Section Guide 
SECTION / SUB-SECTION 

23-00-00 System
23-10-00 Speech Communication 
Description and Operation 

VHF Comm
Troubleshooting

VHF Comm
Wire codes
Maintenance Practices
Removal and Installation
Garmin SL40
Adjustment and Test
Reference to Garmin Manual

23-50-00 Audio Integration 
Description and Operation 

PMA 4000 Audio Panel 
Troubleshooting 

Audio Panel
Maintenance Practices
Removal and Installation

PMA 400 Audio Panel Removal
PMA 400 Audio Panel Installation
Adjustment and Test
Reference to PS Engineering Operation Manual

MAINTENANCE MANUAL SUPPLEMENT 23-10-00-Garmin VHF Comm Radio
C550GT-AD016-FU24-0213
Garmin VHF Comm Radio Revision: Initial Issue DATE: 01/01/2020

Garmin VHF Comm Radio Description and Operation / Communication Sys-
Communication System

23-10-00 Speech Communication

Description and Operation

1. Garmin SL40 VHF Comm

Description and Operation.

A slimline series Garmin SL40 VHF Transceiver, positioned in the LH Instrument Sub-panel, is used for all voice
air-to-air and air-to-ground communications. The unit operates in the 118.000 to 136.975MHz range.

A short rod-type VHF antenna mounts to the top of the fuselage above the cargo area.

The Avionic wiring loom follows a route separate from that of the electrical loom, except across the horizontal
bulkhead to the systems circuit breakers.

Use the Garmin SL40 VHF Transceiver Installation and Maintenance Manual (No. 560-0956-0) for Servicing and
Maintenance.
Go to Aviation Support at www.fly.garmin.com or see the Applicable Publication List in the Preliminary Section of
this CMMS.

Troubleshooting

Ref. Ext. Doc: Garmin SL40 VHF Transceiver Installation and Maintenance Manual (No. 560-0956-0)
NOTE: Refer to Appendix A.

For wiring codes, specifications, connector layout and detailed wiring diagrams refer to the applicable Audio
Panel and VHF Interwiring schematic.
Ref. Dwg. No: AD-550GT-2350-001-101

Removal and Installation

Ref. Ext. Doc: Garmin SL40 VHF Transceiver Installation and Maintenance Manual (No. 560-0956-0)
NOTE: Refer to Section 2.

Adjustment and Test

Ref. Ext. Doc: Garmin SL40 VHF Transceiver Installation and Maintenance Manual (No. 560-0956-0)
NOTE: Refer to Appendix B.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 23-50-01-Audio Integration
C550GT-AD016-FU24-0213
Audio Integration Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Audio Panel

Audio Panel
Audio Integration

23-50-00 Audio Integration

Description and Operation

1. PMA 4000 Audio Panel

Description and Operation

The C550GT communication system has a PMA4000 Audio Panel in the LH Instrument Sub-panel for crew
intercommunication. There two sets of headset sockets on the rear bulkhead and a ‘press to transmit’ switch in
each control column hand grip.
For more information, use the PMA4000 TSO Audio Selector Panel IntelliVox™ Intercom System Installation and
Operation Manual, Technical Data Sheet and Pilot Guide/Operation Manual.
These publications are available at www.ps-engineering.com

Troubleshooting
Ref. Ext. Doc: PMA4000 TSO Audio Selector Panel IntelliVox™ Intercom System Installation/Operation Manual.

For Audio Panel and VHF Interwiring, wiring codes, specifications, connector layout and detailed wiring diagrams
refer to the applicable drawing.
Ref. Dwg. No: AD-550GT-2350-001-101
Removal and Installation
Ref. Ext. Doc: PMA4000 TSO Audio Selector Panel IntelliVox™ Intercom System Installation/Operation Manual.

Adjustment and Test
Ref. Ext. Doc: PMA4000 TSO Audio Selector Panel IntelliVox™ Intercom System Installation/Operation Manual.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 24-00-00 - Electrical Power DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Electrical Power
Chapter 24

Title Page

Chapter 24
Electrical Power

Chapter 24 Electrical Power

MAINTENANCE MANUAL SUPPLEMENT 24-00-00 - Chapter Contents
C550GT-AD016-FU24-0213
Electrical Power Revision: Initial Issue DATE: 01/01/2020

Electrical Power Chapter Contents
Chapter Contents

Chapter Contents

Chapter 24 Electrical Power

Applicable Section Guide
24-00-00 Electrical System
> Electrical System Description.
> Electrical System Operation

Components Changed By This STC
24-30-00 DC Generation
24-30-01 Battery

Description and Operation
> Battery System
> Battery

Maintenance Practices
> Battery Removal
> Battery Installation.

24-30-02 Battery Relay
> Battery Relay Description
> Battery Relay Removal.
> Battery Relay Installation.

24-30-03 Control and Monitoring
> DC Power Generation - Operation
> Generator System Components

24-30-04 Generator Control Unit
> Description and Operation.
> GCU Removal.
> GCU Installation.
Adjustment and Test
> Battery System - Functional Test
> Generator System Functional Test
> Generator Output Voltage Adjustment

24-40-00 Ground Power
Description and Operation.
> Ground Power System

24-40-01 Ground Power Receptacle
Maintenance Practices.
> Ground Power Receptacle (2J1) Removal.
> Ground Power Receptacle (2J1) Installation.

24-40-02 Battery Isolation Relay
> Battery Isolation Relay Removal.
> Battery Isolation Relay Installation.

24-40-03 Ground Power Relay
> Ground Power Relay (2K4) Removal.
> Ground Power Relay (2K4) Installation

MAINTENANCE MANUAL SUPPLEMENT 24-00-00 - Manual to Use DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide

Chapter Guide
Manual to Use

Applicable Section Guide MANUAL TO USE
SECTION / SUB-SECTION
24-00-00 Electrical Power N/A FU24-954 C550GT
Description and Operation
Electrical Description and Operation 
Battery System 
Power Generation System 

24-30-00 Generation System 
Generation System Description 

Troubleshooting
Power and Start Schematic

Maintenance Practices 

Servicing 
Battery System X

Removal and Installation 
Master Switch and Circuit Breakers 
Ammeter X
Batteries 
Master Relay (Battery Relay) X
Alternator X
Voltage Regulator (GCU) X
Over Voltage Relay 
Regulator Filter
Interference Filter
Generator Control Unit

Adjustment and Test 
Operational Test
GCU Voltage Adjustment 
Functional Test 
Generator System
Battery System X
System Test X
Electrical Load Analysis
Bonding Test

MAINTENANCE MANUAL SUPPLEMENT 24-00-00 - Manual to Use DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide
MANUAL TO USE
Applicable Section Guide
SECTION / SUB-SECTION N/A FU24- 954 C550GT
24-40-00 Ground Power
Description and Operation 
Ground Power System Description

Troubleshooting 
Start / Power Electrical Schematic

Maintenance Practices

Removal and Installation 
Ground Power Receptacle 
Isolation Relay

MAINTENANCE MANUAL SUPPLEMENT 24-00-00-Electrical System Description
C550GT-AD016-FU24-0213
Electrical System Description Revision: Initial Issue DATE: 01/01/2020

Electrical System Description Description and Operation / Electrical System
Electrical System
24-00-00 Electrical System
Electrical System Description.
Ref. Dwg. No: AD-550GT-2430-001-001

These components will be covered in the system description.

Component List

Master Switch (2S4)
Battery Isolation Relay (2K5)
Ground Power Relay (2K4)
Ground Power Receptacle (2J1)
Battery Relay (2K3)
Main Power Circuit Breaker (2CB7)
Start Bypass Relay (2K6)
Start Button (2S2)
Generator Switch (2S1)
Generator Circuit Breaker (2CB6)
Auxilec GCU (2VR1P1)
Ignition Switch (2S3)
Ignition Exciter Unit (27400E1P1)
Start Relay (2K2)
Generator Relay (2K1)
Starter Generator (2MG1)
Firewall Pass-through (2TB1)
Firewall Pass-through (2TB3)
Isolating Circuit Breaker (2CB2)
Shunt (2R1)

General

The electrical system is a 28 VDC single wire negative earth return system.
Two internal sources provide electrical power to the system. The Generator System is the main power source
under normal conditions. When power output from the generator is not available (engine not running or
generator failure), battery power provides engine starting and system operation. The Master Switch (2S4)
controls power from the two systems. Both systems supply power to a common bus bar.

Indicating

The MVP-50T Engine Monitor Panel displays VOLTS and AMPS to monitor the system. On the firewall in the
engine bay, the P6 power supply wire from the Starter Generator (2MG1) connects through a 100A fuse to a
copper jumper. A Shunt (2R1) supplies an electrical load signal to the EDC for the AMP display on the Engine
Monitor Panel.
Connectors provide disconnect points for the removal of all major components.
At the LH end of the switch panel there are two sockets, red and black. Use the sockets and a test voltmeter to
check the generator output voltage if necessary. The 10-amp TEST SOCKETS circuit breaker supplies 28 VDC
power to these sockets that can also support ancillary portable equipment.

Circuit Breakers

Circuit breakers or fuses protect all circuits. Wiring is in open looms supported by clips. In critical areas, sleeving
and grommets protect the wiring from chafe or damage. Insulated pass-through studs connect start (P5) and
power (P6) wires at the firewall bulkhead.
The C550GT has two ‘trip-free’ types of circuit breakers in the Circuit Breaker and Switch Panel. A trip-free circuit
breaker is one that will trip (open) even if the trip/reset button is held in the ON (closed) position.
1. Single pole, with manual trip/reset button. When the breaker trips, a white band around the button becomes
visible.
2. Single pole combination switch/circuit breaker. When the breaker trips, the switch toggle returns to OFF.
The switch panel contains the circuit breakers, connected directly to the bus bar. The trip/reset button or switch
toggle has the Amp Rating of the circuit breaker etched on it.The power supply circuit has a 50 amp Isolating
Circuit Breaker (2CB2). If the Starter Generator (2MG1) fails, this circuit breaker can immediately isolate power
to all the non-essential services. The Isolating Breaker is located in the lower RH end of the switch panel.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 24-00-00-Electrical System Description
C550GT-AD016-FU24-0213
Electrical System Description Revision: Initial Issue DATE: 01/01/2020

Description and Operation / Electrical System

Electrical System Operation

The Master Switch (2S4) controls a ground to X2 of the Battery Relay (2K3) through the normally closed contacts
B2-B3 of the Battery Isolation Relay (2K5). The aircraft batteries supply 24VDC to the Battery Relay (2K3) X1
terminal. Set the master switch to ON completes a ground and the Battery Relay (2K3) closes the A1-A2
contacts. In Normal operation, this puts battery power to the Primary Bus.

Ground Power

The electrical system must isolate the battery when the aircraft is on auxiliary ground power. The Battery
Isolation Relay (2K5) does this by controlling the Battery Relay (2K3) on connection of a GPU. The Battery
Isolation Relay (2K5) is adjacent to the battery box. Access is through the Internal Access Door (F17).
On connection of a 24VDC GPU, the small positive pin of the Ground Power Receptacle (2J1) supplies power to
the X2 terminal of the Battery Isolation Relay (2K5) energising it. The relay opens the B2-B3 contact and closes
the B1-B2 contact. This de-energises the Battery Relay (2K3) and provides a ready ground for the Ground Power
Relay (2K4).
At the same time, the receptacle pin supplies power at X1 of the Ground Power Relay (2K4) energising it. This
closes the A1-A2 contacts and connects GPU power supply to the A2 terminal of the Start Bypass Relay (2K6).

Start Power and Circuit Protection

The Start Bypass Relay (2K6), installed on the battery box, has two modes of operation. In bypass mode, it
supplies 24 VDC to the Primary bus through the 100 Amp Main Power loop. If a short did occur, the Main Power
Circuit Breaker (2CB7) protects the supply wiring and components. During engine start, the Starter Generator
(2MG1) load is much higher and this current passes through the main contacts of the Start Bypass Relay (2K6).
This system design is a safety feature. It removes a potential fire hazard from the cockpit when the high-current
engine start-load is not in use.
The Start Button (2S2) is a momentary ON switch. When pressed, it simultaneously supplies power from the 5A
START circuit breaker to the X2 terminal of the Start Relay (2K2) and the X1 terminal of the Start Bypass Relay
(2K6) energising both relays.

Start Sequence and Power Generation

Electrical power through wire P5A2 and the Firewall Pass-through (2TB1) connects to A1 of the Start Relay
(2K2). This energised relay supplies power through A1-A2 to the START terminal of the Starter Generator
(2MG1). The Start Button (2S2) must be closed for the Starter to continue to motor the engine.
The Start Button (2S2) supplies power to the Ignition Switch (2S3) through connection to the X2 terminal of the
Start Relay (2K2). If the Ignition Switch is set to ON and the Start Button held, the Ignition Exciter Unit
(27400E1P1) energises. During the start sequence, the Exciter Unit uses solid-state circuitry to supply a pulsed
high-voltage output. The output connects through braided high-tension cables to two spark igniters.
The same X2 terminal of the Start Relay (2K2), connects power to the START CIRCUIT terminal of the Auxilec
GCU (2VR1P1). The GCU controls field excitation to the Starter Generator (2MG1). The GCU has internal
switching that will ‘open circuit’ the shunt field of the generator allowing it function as a starter motor.
Releasing the Start Button (2S2), de-energises the Start Relay (2K2) and removes power to the Starter and the
GCU. The Starter Generator (2MG1) now reverts to the generate mode and supplies output voltage to the A1
terminal of the Generator Relay (2K1).

Power Generation and Control

Generated voltage from A1 of the Generator Relay (2K1) connects through shielded wire to the 10A Generator
Circuit Breaker (2CB6). The Generator Switch (2S1) is a 3-position Momentary-ON/OFF/ON switch and gets
power from the Generator Circuit Breaker (2CB6). In normal operation, after engine start and Ng is stable at 51-
53%, the GEN Switch (2S1) is set to ON. In this position the switch supplies power to the POWER terminal of the
Auxilec GCU (2VR1P1). The GCU now controls the Generator field excitation and monitors over-voltage and
reverse current. If parameters are in the correct range, the GCU energises the Generator Relay (2K1) through
the Line Contactor circuit and the Starter Generator (2MG1) connects to the Primary bus.
Primary bus power from the GCU RESET circuit breaker connects through the MOM-ON contacts to the RESET
terminal of the Auxilec GCU (2VR1P1). If a system fault occurs, the GCU will trip the line-contactor circuit and
de-energise Generator Relay (2K1). This removes the Generator from the primary bus. If the fault no longer
exists, switching to RESET attempts to put the Starter Generator (2MG1) back on-line.

Page 2

MAINTENANCE MANUAL SUPPLEMENT
C550GT-AD016-FU24-0213
Troubleshooting

Power and Start Schematic
Troubleshooting

24-00-00-Troubleshooting DATE: 01/01/2020
Revision: Initial Issue
Power and Start Schematic

MAINTENANCE MANUAL SUPPLEMENT 24-00-00 - Electrical Sys. Components Changed
C550GT-AD016-FU24-0213
Electrical Sys. Components Changed Revision: Initial Issue DATE: 01/01/2020

Electrical Sys. Components Changed CCBTS / Electrical Power
Electrical Power

Components Changed By This STC

Drawing Number Item Part Number Description / Location

24-30-00 Generation System

AD-550GT-2430-001-000 19 VR1530-3 Voltage Regulator - GCU

AD-550GT-2430-001-000 18 S-300 Shunt

AD-550GT-2430-001-000 17 MS24171 Start Relay

AD-550GT-2430-001-000 17 MS24171 Generator Relay

AD-550GT-2430-001-000 7 AD4STD1M6-47 Firewall Pass-through Stud

AD-550GT-2430-001-000 3 250SG111Q-1 Starter Generator

AD-550GT-2430-001-000 1 10-381550-1 Ignition Exciter

AD-550GT-2430-001-000 6 AD-550GT-2430-001-100 GCU Mount Bracket

AD-550GT-2430-001-000 5 AD-550GT-2430-001-010 Ignition Exciter Bracket

AD-550GT-2430-002-000 1 7035-28 (7000 series) 2 x 12V Sealed Battery

AD-550GT-2430-002-000 12 MS24171-D2 Battery Relay

24-40-00 Ground Power System

AD-550GT-2440-001-000 1 AN2552-3A External Power Socket

AD-550GT-2440-001-000 5 MS25273-D1 Relay (10A)

AD-550GT-2440-001-000 12 MS24171-D2 Relay (200A)

Page 4

MAINTENANCE MANUAL SUPPLEMENT 24-30-01-Battery Sys. Description
C550GT-AD016-FU24-0213
Battery Sys. Description Revision: Initial Issue DATE: 01/01/2020

Battery Sys. Description Description and Operation / DC Generation
DC Generation
24-30-00 DC Generation
Battery System 24-30-01 Battery

Description and Operation

The battery system has of two 12 VDC, in series batteries.

The system supplies power for engine start and operation of the electrical system when the generator is not
running or has failed. The de-energised Battery Relay isolates the battery system from the primary bus bar when
the Master switch is set to OFF.

Battery

The C550GT has two Model 7035-28, 7000 series valve-regulated lead-acid (LT-VRLA) batteries. A single battery
box aft of STA 240.08 contains the batteries, which connect in series.
The Model 7035-28 sealed batteries contain electrolyte absorbed in glass-mat separators. They do not contain
any liquid or ‘free’ electrolyte.

Ref. Ext. Doc: Teledyne Battery Products (Doc. No. Q01-1101) Component Maintenance Manual, LT Valve-Regu-
lated lead-Acid Batteries.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 24-30-01- Aircraft Battery
C550GT-AD016-FU24-0213
Aircraft Battery Revision: Initial Issue DATE: 01/01/2020

Removal & Installation Maintenance Practices / Removal & Installation
Aircraft Battery

Maintenance Practices

1. Battery Removal

Ref. Ext. Doc: Teledyne Battery Products (Doc. No. Q01-1101) Component Maintenance Manual, LT Valve-Regu-
lated lead-Acid Batteries.
Ref. Dwg. No: AD-550GT-2430-002-000

See Figure 24.1

In the cockpit.
(1) Set the master switch to OFF.
(2) Place a placard on the switch panel. DO NOT TURN MASTER SWITCH ON.

In the Cargo Bay.
(3) Remove the Internal Access Door.
(4) Remove lock pins (2) and battery box lid (1).
(5) Slide off the boot, disconnect the earth wire (5).
(6) Slide off the boot, disconnect the positive wire (6).
(7) Remove the joining link (3).
(8) Remove the batteries from the box.

2. Battery Installation.
Ref. Ext. Doc: Teledyne Battery Products (Doc. No. Q01-1101) Component Maintenance Manual, LT Valve-Regu-
lated lead-Acid Batteries.
Ref. Dwg. No: AD-550GT-2430-002-000

See Figure 24.1
(1) Put the batteries in the battery box, leave a gap between them.
(2) Install the separator.

NOTE: Coat the terminals with petroleum jelly to prevent corrosion.
CAUTION: MAKE SURE TO CONNECT BATTERIES IN THE FOLLOWING SEQUENCE.

(3) Install the joining link (3)
(4) Connect the positive wire P2A2 (6) to the positive terminal on the LH battery.
(5) Connect the earth wire P1A2N (5) to the negative terminal on the RH battery.

CAUTION: MAKE SURE YOU FUNCTION TEST THE BATTERY CIRCUIT.

(6) Do a Battery Circuit Function Test. See Chp. 24 Battery System - Functional Test

Page 401

MAINTENANCE MANUAL SUPPLEMENT 24-30-01-Aircraft Battery
C550GT-AD016-FU24-0213
Aircraft Battery Revision: Initial Issue DATE: 01/01/2020

Maintenance Practices / Removal & Installation

Figure 24.1 Battery Installation
Page 402

MAINTENANCE MANUAL SUPPLEMENT 24-30-02-Battery Relay Description
C550GT-AD016-FU24-0213
Battery Relay Description Revision: Initial Issue DATE: 01/01/2020

Battery Relay Description Description and Operation / DC Generation
DC Generation
24-30-02 Battery Relay
Battery Relay Description

NOTE: The FU24-954 Maintenance Manual calls this relay the Master Relay.

The Battery Relay (2K3) is a solenoid-operated bridge-type contactor attached to the LH side of the battery box.
The Battery Master switch controls the relay. When the Master switch is set to the ON position, the relay
connects the battery to the primary and secondary bus bars.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 24-30-02- Battery Relay
C550GT-AD016-FU24-0213
Battery Relay Revision: Initial Issue DATE: 01/01/2020

Removal & Installation Maintenance Practices / Removal & Installation
Battery Relay

1. Battery Relay Removal.

NOTE: What was termed the Master Relay in the FU24-954 is now the Battery Relay in the C550GT Electrical
System.

(1) Remove the batteries. See Chp. 24 Battery Removal
(2) Disconnect the five wires P5C2, P5J2, P2A2, P2B2, P18A22.
(3) Remove bolts, nuts and washers (7).
(4) Remove the Battery Relay (8).

2. Battery Relay Installation.

(1) Install the Battery Relay (8) with bolts, nuts and washers (7).
(2) Connect the five wires P5C2, P5J2, P2A2, P2B2, P18A22.
(3) Install the batteries. See Chp. 24 Battery Removal
(4) Do a Battery Functional Test to check the operation of the Battery Relay. See Chp. 24 Battery System -

Functional Test

Page 401

MAINTENANCE MANUAL SUPPLEMENT 24-30-03-Control & Monitoring - Description
C550GT-AD016-FU24-0213
Control & Monitoring - Description Revision: Initial Issue DATE: 01/01/2020

Control & Monitoring - Description Description and Operation / DC Generation
DC Generation
24-30-03 Control and Monitoring
DC Power Generation - Operation

The Electrical System Operation describes the start sequence. In normal operation, after engine start and Ng is
stable at 52-54% (52% +2 -0), the GEN Switch (2S1) is set to ON. The generator system is now the main source
of power for the electrical system.

Generator System Components

Ref. Dwg. No: AD-550GT-2430-001-001

These components will be covered in the system description:

Starter Generator (2MG1)
Generator Control Unit (Auxilec GCU- 2VR1P1)
Generator Relay (2K1)
Generator Switch (2S1)
Generator Circuit Breaker (2CB6)
Associated wiring and connectors.

Starter Generator (2MG1)
The Aircraft Parts Corporation (Skurka Aerospace Inc.) starter/generator rated at 28V DC - 200A mounts on the
rear upper face of the engine accessory/reduction gearbox module. It is a conventional four pole shunt-field
generator with inter-poles and series auxiliary start windings. A built-in fan cools the unit. See Chp. 80 Start
System Components

Generator Control Unit (2VR1P1)
The Generator Control Unit (GCU) is a solid-state sealed unit mounted on the cockpit floor. The GCU controls the
output voltage of the generator and the start cycle. It protects the aircraft electrical system from over-voltage
and the generator from reverse current flow from the battery. See Chp. 24

Generator Relay (2K1)
The generator relay is a solenoid operated bridge type contactor mounted on the firewall. The relay disconnects
the generator from the primary bus until the Generator Switch (2S1) is set to ON. If the GCU detects electrical
system over-voltage or generator reverse-current flow, it automatically trips the relay.

Generator Circuit Breaker (2CB6)
The 10A GEN circuit breaker is a standard single pole type with manual trip/reset button. It is on the LH side of
the row of circuit breakers in the centre switch panel. The GEN circuit-breaker gives protection to the generator
system if excessive current drain in the generator-shunt field circuit occurs.

Crew Alert System (CAS)
Generation System alerts show on the MVP-50T Engine Monitor annunciator panel. The yellow GEN warning
annunciator illuminates when the master switch is placed ON and goes OFF when the generator comes 'on-line’.
If the generator output fails, the Master Warning Light and the GEN annunciator will illuminate. Refer to the
MVP-50T Engine Monitor Operation Instructions for information on system alerts and warnings.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 24-30-04-G.C.U. Description
C550GT-AD016-FU24-0213
G.C.U. Description Revision: Initial Issue DATE: 01/01/2020

Description and Operation / DC Generation

G.C.U. Description
DC Generation

24-30-04 Generator Control Unit

Description and Operation.

The Generator Control Unit (GCU) is a solid-state sealed unit mounted on the cockpit floor. The GCU controls the
output voltage of the generator and the start cycle. It protects the aircraft electrical system from over-voltage
and the generator from reverse current flow from the battery.
The voltage regulator section of the GCU is adjustable. The adjusting screw, covered by a blanking plate, is
adjacent to the electrical connector.
If the generator voltage exceeds the specified value (32 +/- 0.5 VDC), the generator relay trips the Over-Voltage
protection built into the internal circuit of the GCU.

Page 1

MAINTENANCE MANUAL SUPPLEMENT 24-30-04- Generator Control Unit (GCU)
C550GT-AD016-FU24-0213
Generator Control Unit (GCU) Revision: Initial Issue DATE: 01/01/2020

Removal & Installation Maintenance Practices / Removal & Installation
Generator Control Unit (GCU)

1. GCU Removal.
Ref. Dwg. No: AD-550GT-2430-001-000
The Auxilec GCU mounts on dedicated bracket on the RH side of the cockpit floor.
(1) Remove the wiring connector (2VR1P1).
(2) Remove the four screws (11) that attach the GCU (19) to the bracket (6).
(3) Remove the GCU from the aircraft.

2. GCU Installation.
Ref. Dwg. No: AD-550GT-2430-001-000
(1) Position the Auxilec GCU (19) on the bracket (6).
(2) Install with the four screws (11).
(3) Connect the wiring connector (2VR1P1).
(4) Do a Generator System Functional Test. See Chp. 24 Generator System Functional Test
(5) If necessary, do at Generator Output Voltage Adjustment. See Chp. 24 Generator Output Voltage
Adjustment

Figure 24.2 G.C.U Installation

Page 401

MAINTENANCE MANUAL SUPPLEMENT 24-30-01- Battery System Function Test
C550GT-AD016-FU24-0213
Battery System Function Test Revision: Initial Issue DATE: 01/01/2020

Battery System Function Test Maintenance Practices / Adjustment & Test
Adjustment & Test

Adjustment and Test

1. Battery System - Functional Test
For this test, make sure ground power is not connected to the aircraft. Do not start the engine.

(1) Set all circuit breakers to ON.
(2) Set the master switch to ON.
(3) Use the aircraft systems to put a 10 amp load on the battery.
(4) Monitor the AMPS indication on the MVP-50T Monitor Panel.

Result.
The AMP indication will show a discharge.

(5) Set all load switches to OFF.
(6) Set the master switch to OFF.

NOTE: If the AMPS indication does not show a discharge, find the cause of the fault.

Page 501

MAINTENANCE MANUAL SUPPLEMENT 24-30-01- Generator Function Test
C550GT-AD016-FU24-0213
Generator Function Test Revision: Initial Issue DATE: 01/01/2020

Maintenance Practices / Adjustment and Test

Generator Function Test
Adjustment and Test

Generator System Functional Test

NOTE: Refer to the Approved Flight Manual Supplement STC 14/21E/5. (latest revision) for engine start and
shutdown procedures.

(1) Make sure all circuit breakers are IN.

(2) Set the GEN switch to OFF.

NOTE: On the Main Engine Screen of the MVP-50T, check all the Crew Alert System (CAS) Display
Annunciators. Make sure the GEN FAIL light is ON.

WARNING: MAKE SURE PERSONNEL, EQUIPMENT AND OTHER AIRCRAFT ARE CLEAR OF THE DANGER ZONE
NEAR THE ENGINE.

(3) Start the engine and allow time for it to stabilise.
(4) With the engine RPM stabilised at not less than 52% Ng, set the GEN switch to ON.

Result

The GEN FAIL annunciator on the CAS should be OFF.

(5) On the Main Screen of the Engine Monitor Panel, make sure the AMPS indicator shows a positive charge.
NOTE: Record the AMPS and VOLTS before the next step.

(6) Place a load on the electrical system.
(7) Monitor the AMPS indicator, which should still show a charge.

NOTE: If the battery is in a high state of charge, the change in AMPS will be slight. Except immediately after
engine start.

(8) Check the VOLTS indicator, which should show 27 - 28 VDC.
(9) Switch all system loads OFF.
(10) Shut down the engine.

Page 502

MAINTENANCE MANUAL SUPPLEMENT 24-30-01- Generator Sys. Voltage Adjustment
C550GT-AD016-FU24-0213
Generator Sys. Voltage Adjustment Revision: Initial Issue DATE: 01/01/2020

Maintenance Practices / Adjustment and Test

Generator Sys. Voltage Adjustment
Adjustment and Test

Generator Output Voltage Adjustment

NOTE: Refer to the Approved Flight Manual Supplement STC 14/21E/5. (latest revision) for engine start and
shutdown procedures.

Adjustment Settings and Procedures.

The voltage regulating section of the Generator Control Unit (GCU) is set at 28.5 ± 0.25 VDC by the O.E.M.
manufacturer.

For aircraft operating in temperate climates, CAC recommends that you readjust the system voltage at the GCU
to 27.5 ± 0.25 VDC.

Adjust the generator output under NO LOAD conditions. After engine start, the Master Switch and all service
switches, except the GEN Switch (Generator), must be set to OFF.

(1) In the cockpit, connect a test voltmeter to the voltage test sockets in the Circuit Breaker / Switch Panel.
(2) Start and run the engine to a power setting of 52% Ng.
(3) Set the GEN switch to ON and check that the GEN FAIL annunciator on the Engine Main Screen goes OFF.
(4) Wait 30 seconds for the regulator to stabilise.
(5) Set the Master Switch to OFF.
(6) Make sure all service switches are set to OFF.
(7) Monitor the display on the test voltmeter.
(8) If necessary, adjust the voltage regulator to get a test voltmeter indication of 27.5 +/- 0.25 VDC.

NOTE: The adjusting screw is under a blanking plate, next to the electrical connector. Set the correct voltage
by turning the adjusting screw clockwise to increase the voltage. The adjustment is very fine.

NOTE: Very cold climates may require a higher battery charging rate.

CAUTION: THE MAXIMUM PERMITTED VOLTAGE IS 28.0 VDC.

(9) Momentarily increase the engine power to 80% Ng. Monitor the reading on the test voltmeter to make sure
the voltage is stable at high generator RPM, then reduce the power to 52% Ng.

(10) Set the master switch to ON. Check that the GEN FAIL annunciator on the Engine Main Screen is OFF.
(11) Gradually increase electrical loads and make sure the voltage output stays constant.
(12) Shut down the engine.
(13) Remove the test voltmeter.

Page 503

MAINTENANCE MANUAL SUPPLEMENT 24-40-00-Ground Power Sys. Description
C550GT-AD016-FU24-0213
Ground Power Sys. Description Revision: Initial Issue DATE: 01/01/2020

Description and Operation / External Power

Ground Power Sys. Description
External Power

24-40-00 Ground Power

Description and Operation.

Ground Power System

Ref. Dwg. No: AD-550GT-2440-001-000

This modification introduces an External Power socket mounted internally in the rear fuselage.
You can connect a 28 VDC external power supply (GPU) for engine starting and electrical system maintenance.
The circuit has four component parts. A External Power Receptacle (2J1), Relay (2K4), Isolation Relay (2K5) and
associated wiring.
The Electrical System Description describes the operation sequence. See Chp. 24 Electrical System Operation

External Power Receptacle.

A standard AN2552-3A power socket attaches to a reinforced section of the frame at STA 240.05 (lower LH side).
The socket extends forward through the fuselage frame. With the cargo door open and an applicable plug, you
can use the socket to connect an external power source.

External Power Relay.

The External Power Relay (2K4), on the battery box, is the same component as the Battery Relay. When
energised, it connects the ground power supply to the start relay and the aircraft bus bar.
The Electrical System Description describes the operation of the relay. See Chp. 24 Electrical System Operation

Battery Isolation Relay.

The Battery Isolation Relay (2K5) is a 10-amp, two pole, double action, sealed unit. The relay is located on the
rear of frame STA 240.05, below the ground power socket.
When energised by the external power source, the relay disconnects the circuit between the master switch and
the master relay. This isolates the batteries from the electrical system.
The Electrical System Description describes the operation of the relay. See Chp. 24 Electrical System Operation

Page 1

MAINTENANCE MANUAL SUPPLEMENT 24-40-01- External Power Receptacle
C550GT-AD016-FU24-0213
External Power Receptacle Revision: Initial Issue DATE: 01/01/2020

Removal and Installation Maintenance Practices / Removal and Installation
External Power Receptacle

24-40-01 Ground Power Receptacle

Maintenance Practices.

1. Ground Power Receptacle (2J1) Removal.
Ref. Dwg. No: AD-550GT-2440-001-000
(1) Disconnect the battery. See Chp. 24 Battery Removal
(2) Disconnect the wiring from the receptacle.
NOTE: Tag the wiring for reassembly.
(3) Remove the two screws (2), washers (3) and nuts (4)
(4) Remove the Receptacle (1) from the fuselage frame.

2. Ground Power Receptacle (2J1) Installation.
Ref. Dwg. No: AD-550GT-2440-001-000
(1) Install the Receptacle (1) using the two screws (2), washers (3) and nuts (4).
(2) Connect the wiring to the Receptacle (1).
(3) Connect the battery. See Chp. 24 Battery Installation.
(4) Do a Battery System Functional Test.See Chp. 24 Battery System - Functional Test

Page 401

MAINTENANCE MANUAL SUPPLEMENT 24-40-02- Battery Isolation Relay
C550GT-AD016-FU24-0213
Battery Isolation Relay Revision: Initial Issue DATE: 01/01/2020

Removal and Installation Maintenance Practices / Removal and Installation
Battery Isolation Relay

24-40-02 Battery Isolation Relay

1. Battery Isolation Relay Removal.
Ref. Dwg. No: AD-550GT-2440-001-000
(1) Disconnect the aircraft battery. See Chp. 24 Battery Removal
(2) Remove the tyraps from the wiring loom for access.
(3) Remove the four nuts (7) and washers (6) that attach the Relay (5) to the bracket.
(4) Position the relay and unsolder the wire connections.

2. Battery Isolation Relay Installation.
Ref. Dwg. No: AD-550GT-2440-001-000
(1) Position the Relay (5) and solder the wire connections.
NOTE: For connection detail, refer to AD-550GT-2430-001-001.
(2) Attach the Relay to the mount bracket with the four nuts (7) and washers (6).
(3) Secure the wiring loom with tyraps (11)
(4) Do a Battery System Function Test. See Chp. 24 Battery System - Functional Test
(5) Do the test on the Aircraft Battery. Then connect the aircraft to External Power and repeat the test.

Page 402

MAINTENANCE MANUAL SUPPLEMENT 24-40-03- Ground Power Relay
C550GT-AD016-FU24-0213
Ground Power Relay Revision: Initial Issue DATE: 01/01/2020

Removal and Installation Maintenance Practices / Removal and Installation
Ground Power Relay

24-40-03 Ground Power Relay

1. Ground Power Relay (2K4) Removal.
Ref. Dwg. No: AD-550GT-2440-001-000
(1) Remove the batteries See Chp. 24 Battery Removal
(2) Disconnect the four wires P21A2, P5C2, P19A22 and P20A22
(3) Remove bolts (13), nuts (15) and washers (14).
(4) Remove the Relay (12).

1. Ground Power Relay (2K4) Installation

(1) Install the Relay (12) with the two bolts (13), nuts (15) and washers (14).
(2) Connect the four wires P21A2, P5C2, P19A22 and P20A22.
(3) Install the batteries. See Chp. 24 Battery Installation.
(4) Do a Battery System Function Test. See Chp. 24 Battery System - Functional Test
Do the test on the Aircraft Battery. Then connect the aircraft to External Power and repeat the test.odn

Page 403

MAINTENANCE MANUAL SUPPLEMENT 25-00-00 - Equipment and Furnishings
C550GT-AD016-FU24-0213
Chapter 25 Revision: Initial Issue DATE: 01/01/2020

Title Page Equipment and Furnishings

Chapter 25
Equipment and Furnishings

Chapter 25 Equipment & Furnishings

MAINTENANCE MANUAL SUPPLEMENT 25-00-00 - Equipment & Furnishing
C550GT-AD016-FU24-0213
Chapter Content Revision: Initial Issue DATE: 01/01/2020

Chapter Content Equipment & Furnishing
Equipment & Furnishing

Chapter Contents

Chapter 25 Equipment & Furnishings

Applicable Section Guide
25-60-00 AELS

Description and Operation
> Aircraft Emergency Location System (AELS).
> Maintenance Practices

MAINTENANCE MANUAL SUPPLEMENT 25-00-00 - Manual to Use DATE: 01/01/2020
C550GT-AD016-FU24-0213 Revision: Initial Issue Manual to Use
Chapter Guide
MANUAL TO USE
Chapter Guide
Manual to Use N/A FU24- 954 C550GT

Applicable Section Guide 
SECTION / SUB-SECTION

25-00-00 Equipment and Furnishings
Description and Operation

Seats And Furnishings

25-10-00 Flight Compartment 
Description and Operation 

Seats 
Safety Harness

Maintenance Practices 

Servicing 
See Chapter 12

Removal and Installation 
Cockpit Seat Base
Cockpit Seat Back 
Detachable Bulkhead 
Harness, Inertial ReeL

25-60-00 Emergency Equipment
Description and Operation

Aircraft Emergency Location System (AELS)
Safety Equipment
Maintenance Practices
Removal and Installation
Inspection and Check