1-9
Cisco ONS 15454 SDH Reference Manual, R5.0
April 2008
Chapter1 Shelf and FMEC Hardwa re
1.4 E1-75/120 Conversion Panel
Note The E1-120NP FMEC can only be used in Slots 18–21 and Slots 26–29. The STM1E 1:1 FMEC can only
be used in Slots 18 and 19, 20 and 21, 26 and 27, or 28 and 29.
1.4 E1-75/120 Conversion Panel
You need an E1-75/120 conversion panel if you want to convert the balanced 120-ohm interfaces of the
E1-42 card and the corresponding FMECs to unbalanced 7 5-ohm interfaces.
The E1-75/120 contains eighty-four 1.0/2.3 miniature coax connectors (42 for transmit, 42 for receive)
to the customer side and two Molex 96-pin LFH connectors to the E1-42 FMEC 120-ohm side. Each o f
the Molex 96-pin LFH connectors connects 21 inputs and 21 outputs. The E1-75/120 conversion panel
is intended to be used in digital distribution frames (DDFs), ETSI racks, and ANSI racks.
You can install the E1-75/120 conversion panel in the rack of your ONS 15454 SDH or in a nearby rack.
If you install the E1-75/120 conversion panel in a place where a longer cable is required, make sure that
the total cable loss of the balanced 120-ohm cable and the unbalanced 75-ohm cable does not exceed the
maximum allowed value. Refer to the Cisco ONS 15454 SDH Reference Manual for details. To ensure
that the E1-75/120 conversion panel is secure, use one or two M6 mounting screws for each side of the
shelf assembly. Figure1 -6 on page 1-10 shows the rack-mounting for the E1-75/120 conversion panel.
Note If required, the mounting brackets of the E1-75/120 conversion panel can be uninstalled, rotated
90 degrees, and reinstalled to enable 19-inch (482.6 mm) rack mounting.
FMEC
E1-120PROB
3 to 42 2.048 Mbps Molex 96-pin LFH
connector
EFCA,
Slots 26 to 29
FMEC-E3/DS3 12 34.368 Mbps
44.736 Mbps
1.0/2.3 miniature coax
connector
EFCA
FMEC STM1E 1:1 12 (protected) or
24 (nonprotected)
155.52 Mbps 1.0/2.3 miniature coax
connector
EFCA
Table1-2 FMEC, Ports, Line Rates, and Connectors (continued)
FMEC Ports Line Rate per Port Connector Type Connector Location