(2)
Memory
(3)
Interface electronics
(4)
Power supplies
(5)
BITE, BITE formatting, and monitor circuits
(6)
Synchro drivers
E. FMCS/DAA Interface
(1) The following FMC interface signals are converted as required by the DAA:
(a)
Total Fuel (Left DAA only)
(b)
Command N1
(c)
N1 Limit
(d)
FMC Autotune
(e)
Autotune/Manual Tune Mode
(f)
FMC Agility Tuned DME
(g)
FMC Nav Data Outputs
(h)
FMC Nav Inputs
F. IRS/DAA Interface
(1) The following IRS interface signals are converted as required by the DAA:
(a)
Pitch
(b)
Roll
(c)
Heading
(d)
Yaw Rate
(e)
Ground Speed
(f)
Drift Angle
G. DAA Discrete Inputs
(1) The following discrete inputs are provided to the DAA
(a)
Remote Test
(b)
Oleo strut switch for air/ground logic
(c)
Auto/Manual Tuning
(d)
DME Valid
(e)
VOR/LOC Super Flag
(f)
Localizer Tuned (VOR/ILS)
H. Abnormal operation of the DAA signal processing, such as magnetic heading, causes a malfunction code display on the ISDU and a flag to appear on the associated instrument.
EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. AIRPLANES WITH EFIS ú
34-28-01
ú ú 01 Page 21 ú Nov 15/97
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
737-300/400/500MAINTENANCE MANUAL
I. The DAA's are checked during IRS BITE. Their status is also displayed during FMCS BITE.
J. The DAA accepts 115 volt ac and 28 volt dc power from circuit breakers on the P6 and P18 panels to produce the dc voltages required for the processing of essential and non-essential parameters.
K. Internal circuits include microcomputers whose function is to convert ARINC 429 bus information from the IRU and FMC to analog and discrete signals that are used by the RDDMI's, the yaw damper, and other systems. The signals are pitch, roll, magnetic heading and navigation parameters and the discretes that are valid signals associated with the converted parameters. Other converted signals are N1 limit, N1 bug drive, VHF NAV/DME frequency, and discretes. Each microcomputer consists of a processor, memories, controls, decoders, registers and other associated circuits. The microcomputers decode the ARINC 429 input and, in an orderly routine, supply the words to digital to analog (D/A) converters which convert the digital words into analog signals through the synchro transmitters or into two wire signal outputs. A microcomputer also converts analog inputs to ARINC 429 format for use by the FMC and FCC'S. 26 volt ac is applied as reference to the D/A's to perform the conversions.
8. IRS Master Caution Unit_______________________
A. The master caution unit provides an interface between the IRS system and the airplane's master caution warning system.
B. The IRS master caution unit senses abnormal IRS conditions and controls the IRS master caution light on the left side of the glareshield. The unit also operates the left and right master caution lights by supplying an input to the annunciator and dim module.
C. The unit is installed on the P10 panel near the aft end of the flight deck on the first officers side.
D. The unit contains four cards, one card each for monitoring ON DC, FAULT and DC FAIL Logics, from each IRU and one output card for control of the IRS caution light on the captain's side of the pilots' lightshield.
9. Electronic Attitude Director Indicator (EADI)_____________________________________________
A. The electronic attitude director indicators are multipurpose instruments which display pitch and roll outputs from the IRU's via the EFIS symbol generators. IRS failures cause the ATT valid to fail and the ATT failure flag to appear. The EADI's are located on the captain's and first officer's instrument panels.
B. For a detailed description of EADI operation, refer to AMM 34-22-00/001.
10. Electronic Horizontal Situation Indicator (EHSI)_________________________________________
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本文链接地址：737-300 400 500 AMM 飞机维护手册 导航 NAVIGATION 2(56)
