Essential Install | CEDIA
The great fibre provider
Martyn Goody, senior designer at CEDIA member company,
Marquee Home, discusses the importance of fibre optic
cabling use and pre-wiring in the residential world.
Let’s be clear about this, I’m not talking about All-bran.
Fibre optic cabling has been a main stay of our cabling
architecture for some time now. AV rack locations,
HDTV (now 4K) outlets, Slave audio & network hubs, RF
distribution, and incoming services DP’s all feature a fibre
connection for use within current systems and pre-wires
for systems unknown.
Understanding the
basics of cabling is
key for installers
Single vs Multi?
You have to first understand the basics and the limitations
of any cable that you intend to place in one of your
designs. Should I go single mode or multi-mode? The
reality is that, while single mode fibre has an extremely
high bandwidth, multimode fibre has limited bandwidth
characteristics that significantly influences the maximum
distance that you can transmit high resolution/definition
video signals. There are benefits to both selections; single
mode will carry a greater distance, but on the other hand,
most products feature a multi-mode interface. This is with
the exception of RF distribution, which will only run on
single mode so you have to take this into consideration
when designing a system.
One to use and one to lose
Marquee Home says
there’s been an
uplift in clients
demanding FTTP
(fibre to the property)
We spend a lot of time looking at what is current and what
is on the horizon of technology for our clients. The saying
‘the most expensive cable is the one you forget’ has been
a mainstay for many years so the theory is plan for the
worst and hope for the best. I’m not here to tell you how
you should design your infrastructure because who’s to
say I know better than you?
As a rule of thumb, all our TV outlet plates currently
feature a shotgun multimode fibre OM3 cable from
Cleerline (available through Habitech). We’ve also seen an
uplift in clients demanding FTTP (fibre to the property) in
lieu of the standard FTTC (fibre to the cabinet). Providing
pull ducts from incoming entry points on properties
to FibreFox break out boxes ensure service providers,
such as BT and alike can terminate straight onto the
infrastructure you’ve designed. We use a 63mm green
flexi duct with a built in pull cord for future use and to
date, Virgin have used it alongside Openreach and others.
Point to Point vs Send & Receive?
Simple enough to follow I would guess. We all live in a
world where we use these phrases quite often but it’s not
as it seems. Point to point would be over one cable. Video
over fibre, for example, uses a single fibre from point A to
point B but you still have a sender (HDMI to fibre) and a
receiver (fibre to HDMI). The reason this is point to point is
that the data only travels one way. Send & Receive, on the
other hand, using GBIC’s for networks have a send/receive
on both ends, requiring two fibre cables much the same as
the transmit pair and the receive pair in an Ethernet cable.
Time to polish those ends
It’s not always easy to get a dust free environment on site
and with contractors and clients rushing through projects,
this can be problematic. We’ve used outside contractors in
the past to come in and polish and terminate cables at rack
and outlet end, which works on large scale projects but it’s
not so efficient on a smaller project. With that in mind, the
solution from Cleerline enabled all our engineers to field
terminate both ends without the need to book in a third
party contractor. The cost of the field termination kit was
about the same cost as a third party contractor for the day
so it’s paid for itself many times over already.
More information: Marquee Home marqueehome.co.uk
14 | October 2017