CMCS -GROUND TEST SWITCH INTERFACE

General
The ground test switch does these functions:

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Lets some ground tests operate

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Lets some software load into LRUs

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Provides power to the portable maintenance access terminal (PMAT) in the main equipment center.

The ground test switch sends discrete signals to these components:
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Left and right AIMS cabinets

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PSEU 1 and 2

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Left and right systems card files.

PMAT Interface

The ground test switch sends 115v ac from the left power management panel to the portable maintenance access terminal in the main equipment center.
AIMS Interface

The ground test switch discrete signals go to the M004 IOM and the M003 IOM in the left and the right AIMS cabinets.
The AIMS uses the data conversion gateway function (DCGF) and changes the switch discretes to ARINC 629 formatted signals. The DCGF puts the signals on the systems ARINC 629 buses and the flight controls ARINC 629 buses.
LRUs that connect to the ARINC 629 buses use the data to permit critical tests.
PSEU Interface
The proximity sensor electronics units (PSEU) get a direct input from the switch. The PSEUs use the signal for ground test control.
Systems Card File Interface
The left and right systems card files get switch discretes that show the position of the ground test switch. These are the systems that use the signal to permit ground tests:
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Fire/overheat detection system

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Airfoil and cowl ice protection system

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Duct leak detection system

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Air/ground system

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Hydraulic system

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Environmental control system

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Cargo smoke detection system.

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CMCS -GROUND TEST SWITCH INTERFACE

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CMCS -PMAT INTERFACES

Power

The portable maintenance access terminal (PMAT) in the main equipment center (MEC) receives 115v ac 400 hz from the E/E BAY PMAT circuit breaker on the P110 left power management panel. The PMAT receives power when the ground test switch is in the enable position.
The PMAT in the MEC has a battery disable discrete to disable the battery.
Brouter

The brouter transmits data to and receives data from the ethernet local area network card in all PMATs. The PMATs use a 10 base T interface.
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777 AIRCRAFT MAINTENANCE MANUAL

CMCS -PMAT INTERFACES

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CMCS -FIBER OPTICS INTERFACE

Avionics Local Area Network

The left and right AIMS cabinets have a fiber optics interface which supplies two connections to an avionics local area network (AVLAN). The MAT and a brouter also have fiber optics connections to the avionics LAN. The avionics LAN is part of an onboard local area network (OLAN). The AVLAN supplies a high speed communication path between the AIMS cabinets and the:
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Maintenance access terminal (MAT)

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Portable maintenance access terminal (PMAT)

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Four portable maintenance access terminal (PMAT) receptacles.

The MAT receives data from and transmits data to the avionics LAN through a bypass switch unit (BSU). The MAT controls switches in BSU 2 to connect the MAT to the AVLAN. The MAT uses two discretes, primary bypass switch (BS) 2 high and secondary BS 2 high, to control the switches in BSU 2.
A brouter supplies the connection to the PMAT and PMAT receptacles. The brouter has a network bridging function. The network bridging function supplies the brouter connection to the avionics LAN. The brouter also uses two discretes, primary bypass switch (BS) 2 high and secondary BS 2 high, to control the switches in BSU 1.
The data communication management function (DCMF) in the left and right AIMS cabinets has the communication protocols that permit the AIMS functions to communicate with the OLAN.
The AIMS functions that use the DCMF communication services are the:
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CMCF for software data loading from the MAT and PMAT

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CMCF and ACMF for communications with the maintenance terminal function (MTF) in the MAT and PMAT

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CMCF to record OLAN faults.

EFFECTIVITY BEJ ALL  45-10-00 
　
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