Calrec ARGO, Installation & Technical Manual

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FIBRE SFP CONNECTIVITY
Optical SFP modules for fibre
connectivity can be used for console
to processing core, router to router,
and router to I/O connections.
Fibre connectivity is required when the
cable run between units exceeds the
maximum permissible length for Cat5e/
Cat6 copper cabling. Fibre can also be
used for shorter runs if it is simply the
preferred medium.
Note that this section only concerns fibre
connections made via SFPs. Note that
MADI interfaces also have pluggable
SFPs which depending on what they
are being connected to and may have
single-mode or multimode connections
in and out of the system. Different MADI
interface SFPs are available to provide
various types of MADI fibre interface as
shown below.
Singlemode vs multimode SFP's
The core within multimode fibre is
relatively thick when compared to
singlemode. Light travels through
multimode fibre at multiple angles,
'bouncing' of the sides of the core as it
travels through it, taking multiple paths,
or 'modes' of varying length from one
end to the other, resulting in pulses being
lengthened as they travel. Singlemode
fibre has a very fine core and light travels
in a single, direct path from one end to the
other without affecting pulse length.
The result is that singlemode fibre has
a higher bandwidth capacity and
lower signal loss allowing much
greater distances to be achieved.
Light can be transmitted into multimode
fibre using LED’s or low powered lasers
whilst singlemode uses a higher powered
laser.
Bi-Directional SFP's
These SFP's use a simplex LC connector
and operate by transmitting and receiving
at 2 different frequencies down the same
fibre in opposite directions. These have to
be used in a Type A /Type B pair. Type A
has a TX frequency of 1310nm and a RX
frequency of 1550nm whilst its opposite
uses a TX frequency of 1550nm and a RX
frequency of 1310nm.
Calrec recommend the use of singlemode
fibre whenever possible in order to
maximise the flexibility in the location of
hardware and maintain uniformity across
the system by using a single type. If a
multimode infrastructure is in place, fibre
length, the number of inter-connects and
equipment location becomes important.
SFP modules are available in bi-
directional, singlemode and multimode
fibre types. It is important to select the
correct SFP for the type of fibre being
used in the installation. If using a mixture
of singlemode and multimode fibre, it is
important to ensure the correct SFPs are
matched to the correct fibre type.
Identification
The release button / handles of fibre
SFPs are colour coded - Blue (TypeA) /
Purple or Green (TypeB) for bi-directional,
Blue for singlemode and Black for
multimode.
Blue LC connectors, as shown below
should be used to terminate singlemode
fibre, and beige connectors for multimode.
Connectors / terminations
Calrec fibre bi-directional SFPs
use simplex LC connectors whilst
multimode and singlemode use duplex
LC connectors. The duplex termination
requires two fibres per connection, one is
a send path, the other is a receive path.
When terminating the fibre, the send from
one end should connect to the receive of
the other and therefore they are 'cross-
over', terminated A to B and B to A.
SFP / fibre specifications
Specifications are shown in the table
below. The maximum distances shown
assume a single point to point connection
with no intermediary interconnections.
Losses should be measured across the
total signal path including interconnects -
between points of transceiver connection.
Losses need to be less than the optical
power budget of the SFP transceivers.
SFP COPPER / FIBRE SPECIFICATIONS
Part
Number Description /Cable Type Type TX
Freq RX
Freq Bale
Colour Max
Dist Connector
Type GBIC
Type Power
Budget
491-194 SFP Module Copper CAT5/6 N/A N/A N/A N/A 90m RJ45 N/A N/A
491-087 SFP Module Fibre Multimode 62.5/125um N/A 850nm 850nm Black 275m LC Duplex SX 7.5dB
As above SFP Module Fibre Multimode 50/125um N/A 850nm 850nm Black 550m LC Duplex SX 7.5dB
491-072 SFP Module Fibre Singlemode 8/125um N/A 1310nm 1310nm Blue 10km LC Duplex LX 8.0dB
491-060 SFP Module Fibre Singlemode 8/125um N/A 1310nm 1310nm Blue 70km LC Duplex LH 23.0dB
491-195 SFP Module Fibre Bi-Directional 9/125um A 1310nm 1550nm Blue 10km LC Simplex LX 11.5dB
491-196 SFP Module Fibre Bi-Directional 9/125um B 1550nm 1310nm Purple 10km LC Simplex LX 11.5dB
491-201 SFP Module Fibre Bi-Directional 9/125um A 1310nm 1550nm Blue 40km LC Simplex LH 23.0dB
491-200 SFP Module Fibre Bi-Directional 9/125um B 1550nm 1310nm Green 40km LC Simplex LH 23.0dB
DUPLEX LC FIBRES CORRECTLY TERMINATED A TO B & B TO A
BI-DIRECTIONAL LC FIBRE CORRECTLY TERMINATED TYPE A TO TYPE B
A B
A
A
B
B