Most wire and cable jackets are water-resistant-- PVC, polyethylene, and Teflon included-- but sometimes full water blocked cable is needed. Whether it is near a standing body of water or simply in just a moist environment, extra protection may be needed. Even if the water or moisture doesn’t make its way through the jacket entirely, it can still affect the signal and performance strength of the wire.

Water-damage can be prevented by choosing strong jacket materials, like high-density polyethylene instead of PVC. Sometimes, an extra layer of protection is required due to wire function. This means the wire needs to be fully water blocked. There are two kinds of water blocking: dry and gel.

Dry water-blocking entails adding an extra layer of protection between the jacket and everything inside it. This extra layer of cloth will soak up any water that may work its way through the jacket, and won’t cause any interference. Gel water blocking can add even more protection. Gel gets applied to a braided shield or is extruded on top of a foil shield. Even though it adds more protection, the gel isn’t conductive and would need to be removed where a connector is needed.

Our Custom Waterblocked Cable Solution

At Allied Wire and Cable, we have plenty of experience with custom made wires. In one specific case, Allied Wire and Cable was contacted by a development company designing electrical features for an airport. They needed special accommodations for their new project: a communication cable that controlled the flashing lights for an Approach Lighting System Flasher (ALSF) on the airport runways that would be installed underground and on a pier that extends into the water.

Even though the cable would be run through a conduit, the customer had concerns about the cable lying in the water. Our sales engineer recognized the customer’s worries and determined that custom water blocked cable was needed to ensure the safety and efficiency of the cable. The cable needed to meet as many FAA-spec requirements as possible, as needed a specific mutual capacitance to be met.

There is no standard for water blocked cable with this design, so Allied Wire and Cable constructed a custom 18 AWG,12-pair, water blocked, low-density cable with polyethylene insulation and jacket. For added durability, each pair was given an individual braided shield, providing 95 percent coverage.

Because of our custom design and open line of communication, this customer received exactly what they needed and had a wonderful experience with Allied Wire and Cable. If you would like any other information on a custom water blocked cable, check out our available collection here or design your own here.