(2)
Card fault codes correspond to card slot position in the PSEU.
(3)
Power supply and discrete input fault codes are numbered from 400 to 407 and 421 to 426 respectively.
(4)
All fault code numbers are listed on the PSEU front panel placard. Additional placards on the inside of the PSEU front panels provide card information.
2. Component Details
__________________
A. Proximity Switch Electronics Unit (PSEU) (Fig. 2, 2A)
________________________________________
(1)
The PSEU (M162), located on the E3-4 shelf in the main equipment center, consists of the following:
(a)
Six interchangeable prox cards
(b)
Three logic cards (two interchangeable, one non-interchangeable)
(c)
Three interchangeable driver cards
(d)
A BITE module composed of two unique BITE cards and a control panel
(2)
The PSEU chassis accommodates 12 active cards, 3 spare cards, and a BITE module.
(3)
All PSEU cards are line replacable units (LRU's) and are accessed through hinged panels on the front of the PSEU (Fig. 2A). It is not necessary to remove the PSEU from its shelf to access the cards.
(a)
A placard on the inside of each hinged front panel provides card type and slot locations. The placards also show specific sensor and prox, logic, and driver card relationships (as defined by their card slot locations) for each of the systems monitored by the PSEU.
(4)
Each subsystem operates from its own 28V dc power supply. These supplies are at the card interface to provide power for the appropriate logic section. Thus loss of power to any subsystem will not affect the others.
B.
Prox Card
_________
(1)
Each prox card can monitor the relative sensor target positions of up to 16 sensors.
(2)
The prox card supplies a periodic pulse to drive sensors and monitors the return voltage from the sensor. Since sensor inductance varies with target proximity, the prox card determines target near or far condition by measuring return voltage.
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MAINTENANCE MANUAL
PSEU (ON E3-4 SHELF
OF E/E EQUIPMENT CENTER)
SEE C
SEE A BITE PANEL
SEE B INSTRUCTIONELECTRONICS LABELSACCESS DOOR, ON COVERS119BL (REF) (FRONT AND BACK)
TARGET FWDPANEL LAMPNEAR OR FAR
TEST SWITCH AINDICATOR
LIGHTS (2)
THUMBWHEEL
SENSOR
CHANNEL
SELECTOR
SWITCHES (3) DRIVER (006) LOGIC (011)
PROX (012)
LOGIC (005) DRIVER (010) SPARE SLOT
PROX (004) DRIVER (007) PROX (014)PROX (003) LOGIC (009) PROX (015)
PROX (002) SPARE SLOT
SPARE SLOTLRU NUMBER
3-DIGIT
DISPLAY
LRU
INDICATOR
LIGHTS (3)
TARGET
SYSTEM TEST
TEST SWITCH
SWITCH
BITE
MODULE
(008)
INFLIGHT MALFUNCTION RECALL SWITCH SWITCH (RECESSED) MEMORY RESET HINGED PANEL BITE PANEL CARD POSITION HINGED PANEL
BITE PANEL (TOP VIEW WITH COVER REMOVED)
B C
Proximity Switch Electronics Unit (PSEU)
Figure 2
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MAINTENANCE MANUAL
HINGE PANEL (2 PLACES)
PSEU CARD SLOT/TYPE PLACARDS
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