Mitel SX-200 Documentation page 13

MAINTENANCE
SYSTEM POWER
Figure 2-4
Maintenance
2.09 The maintenance panel (Figure 2-4), mounted at the top of the
cabinet, provides access to the system from the maintenance
console through a 50-pin connector. To the left of the maintenance
plug is the master power failure transfer switch and five power fail
transfer control switches. In addition, a test line is provided which
allows service personnel to access individual lines and trunks.
Equipment
2.10 Mounted directly below the maintenance panel is the equipment
shelf. This shelf contains the system control logic plus a num-
ber of trunk, line and receiver cards. All connections between shelves
and external equipment are made by connectorized cables from the
rear of the shelf. The system primary power supply, located to the
right of the equipment shelf, converts the commercial input power to
the required system voltage levels.
2.11 The equipment shelf holds up to 20 printed circuit cards which
plug into the shelf backplane. On the rear of the backplane are a
number of Amphenol
shelves and external equipment. In addition to the plugs are a number
of screw-down terminals allowing shelf connection to the primary
power supply unit. The equipment shelf (Figure 2-5) measures 273 mm
(10.75 in.) high, 480 mm (19 in.) wide, 415 mm (16.375 in.) deep and
weighs approximately 12.2 kg (27 lb) fully equipped.
Printed Circuit Cards
2.12 All circuit cards (Figure 2-6) within the system are identical in
construction and consist of a fiberglass board with printed
wiring patterns on both of its faces. Riveted to the front of each board
is a transparent faceplate which allows the LEDs mounted on the front
of the boards to be easily seen. The color-coded card extractors
located at the top and bottom of the faceplate identify the card posi-
tion within a shelf and ensure that the card is seated correctly in the
backplane connector.
SECTION MITL91 OS/91
CONSOLE COMMON
MASTER
POWER C0NTRoL
S W I T C H
SUPPLY I NORMAL
SX-100 Maintenance
Panel
Shelf
plugs providing interconnections between the
10-096-l 00-NA
MAINTENANCE CONNECTOR
Panel
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