D. Aural Synthesizer Cards
 (1)  The aural synthesizer cards generate and amplify all warning aurals except windshear, ground proximity and TCAS warnings which are amplified only.
 E. Configuration Warning Card
 (1)  The configuration warning card performs these functions:
 (a)  
Takeoff configuration warning

 (b)  
Landing configuration warning

 (c)  
Speedbrake alert

 (d)  
Stabilizer green band indication

 (e)  
Glide slope antenna switching

 F. Crew Alerting Card
 (1)  The crew alerting card performs these functions:
 (a)  
Flight crew chime aurals activation/inhibits

 (b)  
Altitude alert

 (c)  
Audio output gain levels of ASC.

 G. Tail Identification Card
 (1)  The purpose of the airplane tail identification card is to decode the nine alphanumeric buttons on the MAWEA monitor panel. The resulting airplane identification code is sent to the EIUs on an ARINC 429 bus.
 H. Signal Collection Cards
 (1) The signal collection cards monitor the status of various discrete signals and route them on an ARINC 429 data bus to the EIUs.
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 31-51-00
 ALL  ú ú 09 Page 7 ú Feb 18/01
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

 (2)  These cards also have the capability of receiving two ARINC 429 data buses. The data received on those two data buses is collected into a single ARINC 429 data bus along with the discretes and sent to the EIUs.
 I. Stall Warning Management Cards
 (1)  The details of the stall warning management cards are covered in the Stall Warning System (AMM 27-32-00).
 J. Digital Flight Data Acquisition Card (DFDAC)
 (1)  The details of the DFDAC are covered in the Flight Recorder System (AMM 31-31-00).
 5. Operation (Fig. 5)
_________
 A. Functional Description
 (1)  
A fault monitoring circuit continuously monitors the output voltages of the power supplies. In the event of a loss of output voltages, discretes are sent to the MAWEA monitor panel and to signal collection card No. 1.

 (2)  
The discretes cause the red LEDs (Fig. 3) labelled POWER SUPPLY A FAIL and POWER SUPPLY B FAIL on the MAWEA monitor panel to illuminate. Signal collection card No. 1 monitors the discretes, converts them into a digital format and sends them to the EFIS-EICAS interface units (EIUs). The EIUs generate the message WARN ELECTRONICS on the main EICAS display.

 (3)  
Reset

 (a)  Whenever power is first applied or restored to the power supply, a pulse is sent to all the MAWEA cards to reset their microprocessors.
 NOTE: When applying power to the MAWEA, be sure power is first
____ applied to the captain's and first officer's aural warning speakers.
 (4)  All of the MAWEA cards except for the power supplies are microprocessor controlled and have these features:
 (a) One red LED for displaying faults within the card
 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

 31-51-00
 ALL  ú ú 06 Page 8 ú Oct 10/94
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL

RIGHT STALL 
WARNING CARD 
(ULC) 
MAWEA  MASTER MONITOR 
MONITOR  CREW ALERTING  CARD B (ULC) 
PANEL  CARD (ULC)  RIGHT AURAL 
LEFT AURAL  SYNTHESIZER  SIGNAL 
SYNTHESIZER  CARD  COLLECTION 
INPUT/OUTPUT CONNECTOR  CARD  CARD NO. 2 (SCID) 
SIGNAL 
COLLECTION 
CARD NO. 4
(SCID) 
AIRPLANE TAIL 
IDENTIFICATION 
CARD (SCID) 
STALL CARD WARNING LEFT  DIGITAL CARD ACQUISITION FLIGHT DATA 
(ULC) 
POWER 
SUPPLY B 
MASTER  (INSIDE) 
MONITOR 
CARD A 
(ULC) 
SUPPLY A POWER (INSIDE)  ELECTROSTATIC (IN CORNER) JACK 
　
中國航空網(wǎng) m.k6050.com
航空翻譯 www.aviation.cn
本文鏈接地址：747-400 AMM 飛機(jī)維護(hù)手冊 指示/記錄系統(tǒng) 2