UV Resistant Cable That Stays Resistant

Ultraviolet damage is a slow failure, which is what makes it expensive. A cable installed in direct sun looks perfect for two summers. Then the plasticiser migrates out of the jacket, the surface chalks, hairline cracks open along the run, and water starts entering a cable that is stapled to a roof edge forty feet up. The network fault that follows is blamed on the switch, the access point, or the weather — rarely on a jacket compound chosen three years earlier.

Wider Cable has built Ethernet cable since 2005 with raw-material-to-finished control, so the jacket compound is a decision we make, not one we inherit from a supplier. Our outdoor line uses a c(UL)-listed CMX Outdoor / CMR jacket formulated to resist ultraviolet exposure and cold, over F/UTP shielding.

What ultraviolet actually does to cable

Sunlight carries enough energy to break the chemical bonds in a polymer chain. In an unprotected jacket that shows up in a predictable sequence:

1. Surface chalking — the finish dulls and leaves a powdery residue on the hand.
2. Embrittlement — the jacket loses flexibility, so any movement at a fixing point starts a crack.
3. Cracking — usually first at bends, cable ties and clips, where the material is already under stress.
4. Ingress — water reaches the core, and insertion loss and return loss drift out of specification.
5. Shield corrosion — on shielded constructions, moisture at the foil undoes the very bonding path the shield was installed to provide.

Two things slow that sequence down: a compound formulated for exposure, and pigment or carbon loading that stops the light reaching the polymer in the first place. Both are formulation choices made before extrusion — nothing applied afterwards fixes a jacket that was not specified for sun.

Where it matters most

• Rooftop and façade runs to access points, antennas and cameras, where replacement means access equipment.
• Car parks, stadiums and open yards — long horizontal runs with no shade at any point in the day.
• Solar and utility sites, where the monitoring network sits in the same unshaded field as the array.
• Marine and coastal installations, which combine ultraviolet exposure with salt.
• Aerial spans between buildings, exposed on every side and under constant mechanical load from wind.

How we build it

Where a run leaves the weather and re-enters a building, the fire performance required inside may differ from the jacket used outside. Tell us where the transition happens and we will specify it properly rather than running one jacket end to end and hoping the inspector agrees.

Certification and testing

Every cable is Fluke-tested before it ships. Across the range we hold UL, c(UL), ETL, CPR, RoHS, REACH, CE, SGS, ISO and TÜV. If your specification calls for a particular reaction-to-fire class for the indoor section, raise it at quotation and we will confirm what we can supply.

Ordering and customisation

We manufacture on an OEM/ODM basis. Send the category, shielding, run lengths, installation method, colour and any private-label or packaging requirement, and we quote a defined construction. For requirements outside our standard outdoor build, the custom cable service covers development from drawing through first article to production.

Related: Outdoor Ethernet cables · Water resistant cables · Outdoor PoE cables

Common questions

Is black cable automatically UV resistant?

No. Colour helps — carbon loading blocks light effectively — but resistance comes from the compound, not the shade. A black jacket made from an indoor compound still degrades outdoors.

Can I get UV resistant cable in a colour other than black?

Ask at quotation. Around nine colours are available across the range, but pigment choice and exposure performance interact, so we confirm the combination rather than assume it.

Does the same cable handle rain and standing water?

Our outdoor construction is built for exterior exposure, but sustained immersion or a duct that holds water is a separate specification — see water resistant cables and tell us the conditions.

Do you supply test evidence with the shipment?

Yes. Fluke test results ship with the order, along with the certification documents relevant to the construction supplied.