Coaxial cable carries a signal inside a screen, and everything about how well it works comes
down to whether that screen stays continuous and whether the connector stays tight. In an office
neither is difficult. On a plant, both are: vibration works a connector loose over months, and
salt or moisture creeps into the joint and corrodes the contact surfaces until the signal
degrades. The symptom is not a clean failure but a picture or a signal that gets gradually worse,
which is the hardest kind of fault to attribute.
These are factory-made assemblies rather than cable and connectors fitted on site, and that is
the main argument for them. A coaxial connector terminated by hand in a cabinet at height, in a
hurry, is the single most common source of RF faults - the braid gets nicked, the dielectric
gets crushed, the crimp is uneven. A pre-made assembly is terminated under controlled conditions
and tested before it ships.
Three features address the industrial environment specifically. The connectors are nickel
plated with gold contacts, and the reason given is exactly right: gold resists the corrosion
that can weaken a signal. Gold does not oxidise, so the contact resistance at the mating surface
stays where it started rather than climbing over years. The assemblies are IP68 rated, which
means sealed against dust and against prolonged immersion - a higher bar than the IP66 or IP67
usually seen on outdoor equipment. And the BNC connectors lock, with a polarised interface that
ensures proper mating, so the connector cannot be half-seated or misaligned and then vibrated
apart.
BNC is the appropriate connector choice here rather than a dated one. It is a bayonet fitting
that locks with a quarter turn, so it is quick to make and remove with gloved hands and does not
need a spanner, and it remains the standard interface for video and for a great deal of
instrumentation. The polarised, locking industrial version keeps the convenience while removing
the one weakness of a standard BNC, which is that it can be knocked loose.
Assemblies come in defined lengths - the A200-010-BNC is 10 feet, or 3.05 metres - and
choosing lengths is part of the design rather than an afterthought. A coaxial run that is too
long has to be coiled, and a tight coil changes the cable's characteristics and invites damage;
too short and someone will add an in-line adaptor, which introduces exactly the unsealed joint
the assembly was bought to avoid. Eaton cite these for AV transmission in manufacturing and
warehousing environments, and we specify lengths against the actual cabinet-to-device
distances.
