7/27/2019 74-10-03

1/8

7/27/2019 74-10-03

2/8

Page 2May 16/05

AGUSTA AB 139 TRAINING MANUAL

74-10-03

SECTION 74-10

ELECTRICAL POWER SUPPLY

DESCRIPTION

The ignition provides the initial spark to ignite the fuel/air mixture.The system consists of a dual output ignition exciter, twohigh-tension cable assemblies and two spark igniters.The unit generates sparks in the 10 to 30 VDC range andis located on the upper deck, just after the main transmis-sion.

OPERATIONThe ignition exciter is a sealed unit containing electroniccircuitry encased in an epoxy resin.It transforms the DC input into a pulsed high voltage out-put.It is a dual channel capacitor discharge type that has thecapacity of storing 1.25 Joule of energy at an output volt-

age of 8 kW.The ignition can be performed in two ways: automaticallyor manually (according to the starting type) selected bythe AUTO/MANUAL switch on the pilot collective stickpanel.

The automatic ignition is starting by setting the ENG 1 or

ENG 2 MODE selector switch of the ENGINE CONTROLPANEL to IDLE or FLT.During this phase, the MFD will display the green legendIGN aside the ITT scale on the primary and secondaryVMS information page.It is disengaged when the EEC senses that the enginespeed value is at 50 1% NG.In case the automatic mode cannot be performed, theMANUAL mode is selected via the AUTO/MANUAL switchof the pilot collective stick panel and the starting sequenceis initiated by pressing the START button on the ENGINECONTROL PANEL.

As the engine speed reaches the 49 1% NG, the ignitionsequence is stopped automatically by the relative GCU.

Also during the manual start the legend IGN will be dis-

played.

7/27/2019 74-10-03

3/8

Page 3May 16/05

AGUSTA AB 139 TRAINING MANUAL

74-10-03

CONTROLS AND INDICATORS

The ENGINE CONTROL PANEL housed on the overheadpanel and the pilot collective levers are instead involved inthe ignition-starting system when the automatic mode isperformed.

The ENGINE CONTROL LEVER housed on the overheadpanel and the pilot collective levers are instead involved in

the ignition-starting system when the manual mode is per-formed.The MFD provides the only green legend IGN during theignition.

The ENGINE CONTROL PANEL provides the followingfunctions:

ENG 1 (2) MODE selector switch : OFF - when the N. 1 (2) engine not running or it

shuts down the engine or during the N. 1 (2) enginedry motoring procedure when Manual selected

IDLE - allows the N. 1 (2) engine starting, the mini-mum on ground (65% Npt) and the N. 1 (2) enginestabilization for a period of 60 sec. during the shutdown phase or during the N. 1 (2) engine wet motor-

ing procedure both Auto or Manual mode

The pilot collective stick provides the following functions: ENG 1 (2) GOV AUTO/MANUAL selector switch :

AUTO - allows the N. 1 (2) engine automatic startingand provides the N. 1 (2) engine automatic control

MANUAL - allows the N. 1 (2) engine manual start-

ing / wet motoring / dry motoring and provides the N.1 (2) engine manual control

NOTE When in MANUAL mode, the amber legend MANin reverse video is displayed on the left side of TQscale (MFD Main and Cruise pages) and PI scale(PFDs).

The ENGINE CONTROL LEVER provides the followingfunctions:

ENG 1 (2) START push-button switch : when pressed, the N. 1 (2) engine manual starting /

dry motoring / wet motoring is engaged in Manualmode

7/27/2019 74-10-03

4/8

Page 4May 16/05

AGUSTA AB 139 TRAINING MANUAL

74-10-03

N. 1 IGNITION EXCITER COMPONENT LOCATION

7/27/2019 74-10-03

5/8

Page 5May 16/05

AGUSTA AB 139 TRAINING MANUAL

74-10-03

IGNITION SYSTEM CONTROLS

7/27/2019 74-10-03

6/8

Page 6May 16/05

AGUSTA AB 139 TRAINING MANUAL

74-10-03

IGNITION SYSTEM INDICATING

7/27/2019 74-10-03

7/8

Page 7May 16/05

AGUSTA AB 139 TRAINING MANUAL

74-10-03

SCHEMATIC

TBD

7/27/2019 74-10-03

8/8

Page 8May 16/05

AGUSTA AB 139 TRAINING MANUAL

74-10-03

THIS PAGE INTENTIONALLY LEFT BLANK