747-400 AMM 飞机维护手册 发动机燃油和控制 1(103)

曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

 12. Supplemental Control Unit (SCU) (Fig. 1)
_______________________________
 A.  The SCU supplies an alternate power source to the EEC from a conditioned aircraft power source. The SCU also supplies automatic engine start through the engine autostart controller.
 B.  In addition, the SCU monitors engine temperature (T2.5) and pressure (PT2.5) parameters for engine diagnostic/condition monitoring functions. The parameter of the T2.5 and PT2.5 is found through a combination sensor of temperature/pressure/N1 speed transducer. The SCU supplies the monitored data to the data management unit as part of the aircraft condition monitoring system (AMM 31-35-00/001).
 C.  The SCU is installed, with vibration isolation mounts, on the fan case at the 3 o'clock position.
 D.  If there is an EEC alternator (N2 transducer) malfunction, the power conditioning function in the SCU uses 28 volts dc power from the airframe and supplies a second source of EEC power.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 73-21-00
 ALL  ú ú N03 Page 20 ú Jun 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
E.  The Engine Autostart Controller
 (1)  
When the autostart feature is used, the engine autostart controller in the SCU supplies automatic sequence of the engine start.

 (2)  
The engine autostart controller does not cause problems with the normal ability for manual start, or for wet or dry motoring.

 (3)  
The engine autostart controller monitors the important engine parameters and takes necessary action when engine start anomalies occur.

 (4)  
The SCU disengages the autostart system when the engine gets to idle and does not cause problems with normal engine operation more than idle.

 (5)  
For more data on the autostart system, refer to AMM 80-11-00, Starting - Description and Operation.

 F.  
There are four electrical connectors (J1, J2, J3, J5) on the aft side of
 the SCU [the fifth electrical connector (J4) is for the SCU programming
 plug]. Inputs and outputs of each connector are as follows:

 (1)  
J1

 (a)  
Airframe power - 115 volts ac, 400 Hz input

 (b)  
Airframe power - 115 volts ac, 400 Hz output

 (c)  
Ignition exciter 1 power

 (d)  
Ignition exciter 1 return

 (2)  
J2

 (a)  
N2 speed signal input

 (b)  
EEC CH-A power

 (c)  
EEC CH-A return

 (d)  
EEC CH-B power

 (e)  
EEC CH-B return

 (3)  
J3

 (a)  
Airframe power - 28 volts dc input

 (b)  
Airframe power - 28 volts dc return

 (c)  
Digital data (ARINC) input

 (d)  
Digital data (ARINC) output

 (e)  
Fuel condition motor on

 (f)  
Fuel condition motor off

 (g)  
Fuel condition motor "ON/AUTO"

 (h)  
Start valve output

 (4)  
J5

 (a)  
Airframe power - 115 volts ac, 400 Hz input

 (b)  
Airframe power - 28 volts dc return

 (c)  
Ignition exciter 2 power

 (d)  
Ignition exciter 2 return

 G.  
The SCU contains the seven electronic modules that follow:

 (1)  
Analog Input Module Assembly

 (2)  
Central Processing Unit (CPU) Memory Assembly

 (3)  
Power Converter Module Assembly

 (4)  
Pressure Transducer Mark IIIA Module

 (5)  
Autostart Module Assembly

 (6)  
Storage Bank Module Assembly

 (7)  
Conditioned Aircraft Power Module Assembly

 13. SCU Programming Plug (Fig. 1)
____________________
 A.  The SCU programming plug gives engine serial number data.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 73-21-00
 ALL  ú ú N03 Page 21 ú Jun 18/00
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
　
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：747-400 AMM 飞机维护手册 发动机燃油和控制 1(103)