![]() It also features a CPE jacket with water-blocking tape that resists and blocks water to protect against water intrusion. Sunlight resistant, oil resistant and flame retardant, this cable is built to withstand whatever situation it encounters underground. ![]() If the application involves oil for lubrication of moving parts, then a cable with an oil-resistant jacket may also be needed.īelden’s direct-burial RS-485 Cable is in a class all its own: few, if any, RS-485 cables in the market today have a direct-burial rating.ĭesigned for use in high-end industrial control systems, the cable saves time, material and labor costs because it’s installable directly underground without a separate conduit. If you’re running cable across long distances or alongside power lines, a PLTC-rated cable may be necessary. In industrial environments there are two common cable ratings to consider:Īlthough they’re very similar, there’s one important difference: TC is rated at 600V and PLTC is rated at 300V. Then fill it with gravel according to the specifications of your local jurisdiction, lay the cable on top and bury it.Ĭomplementary Ratings and Characteristics to Considerīased on your application, supplemental ratings may be necessary to consider as you select a direct-burial cable. An example is to start by creating a narrow ditch (appropriate depth depends on whether the cable is being placed under soil, concrete, etc.). There are many methods to install a cable underground, reference the NEC Article 300 prior to installing. Overall, direct-burial cable supports a much faster and easier installation (with less material and time required). When it’s time to install, two separate labor expenses are involved: one for conduit installation and an additional cost to install and pull the cable through. In these situations, two separate costs are incurred: cable material expenses and conduit material expenses. If you need to run cable underground, but choose not to use direct-burial cable, then conduit is required. Using conduit will protect your cables & signals underground-however, it adds another layer of complexity and cost to your project. ![]() To put it simply: If you don’t want to use conduit in your installation, then using a cable with a direct-burial rating is a must. Featuring a rugged jacket, the cable can survive being stepped on, being installed on top of rock or having long-term contact with water-without tearing or negative impact on the performance. To make the “direct burial” claim, third-party testing and ratings are necessary to verify that the cable has the mechanical properties necessary to withstand the rigors of being used in outdoor, underground applications.Ĭonstructed almost as if it has its own, built-in conduit for crush resistance, direct-burial cable is thoroughly tested to pass the same mechanical stresses a typical conduit endures. It also must be PLTC-rated which includes passing the UL 1685 flame test. A copper data cable that gets wet does not work! Underground burial cable type also lacks the mechanical strength necessary for underground direct burial.ĭirect-burial cable is a UL rating earned once a cable passes insulation water absorption and crush-resistance tests. The distance between the two conductors in a pair and the shields is critical to the overall cable balance in regards to NEXT and RL performance which affects system stability. Wet data cable changes the electrical characteristics of the cable as it introduces another conductive element, water, between each pair or singles. If a data cable gets wet, it will have higher attenuation which may impact performance in the field. In general, PE cable jacket has better water resistance than PVC jacket, CPE cable jacket is even higher in water resistance than PE jacket. Water-blocking fillers or polymer gel are designed to stop infiltration in an underground burial cable, but the jacket might not be water resistant over a prolonged period of time water can ultimately migrate to the core of the cable if exposure lasts long enough. Without this protection, the cable can’t withstand underground exposure. Underground burial cable can be installed underground-if it sits inside conduit. It withstands moisture and high and low temperatures, and resists abrasion and tearing-but isn’t designed to be directly buried underground. Outdoor cable features outdoor ratings and maintains performance despite harsh conditions. ![]() Let’s take a closer look at three types of cable often considered for outdoor applications. Three cable types normally rise to the surface in discussions about outdoor installation:īut not every cable that is outdoor-rated or says “burial-rated” can be directly buried underground with no protection. ![]()
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