December 2012
Quabbin Wire & Cable Co, Inc. upgrades their DataMax® line of Low Smoke Zero Halogen (LSZH) F/UTP category 5e, 6 and 6a patch cables. Always a recognized leader in LSZH products, Quabbin’s previous LSZH patch cables included IEC ratings for flame, smoke and corrosive gas. The upgraded constructions now proudly boast the widely recognized NEC and CEC Type CMX building ratings. As required for the CMX rating, the cables have undergone a further battery of testing including tensile/elongation, dielectric, cold bend and aging as well as the VW-1 flame testing. Since the CMX approval is recognized in NEC/CEC building code these cables and their new rating will be recognized by local inspectors as being fully approved.
Although solid conductor, horizontal versions of LSZH data cables are available in the marketplace, stranded patch cable in UL approved LSZH versions are scarce, especially in bulk reels. Most of the spotty availability is limited to pre-terminated cords. Quabbin has filled the market gap by offering the new LSZH stranded patch cable in bulk (1000ft) reels and stocking it for immediate delivery.
Why LSZH and why now?
The halogen family of chemicals includes astatine, chlorine, bromine, fluorine and iodine. The most common in cabling are chlorine found in PVC cables and fluorine found in the FEP (Teflon) used to make plenum designs. To begin with, halogens act as an inexpensive flame retardant and have been used in cabling for years. Although they can resist flame very well, once they do burn, they release very dangerous gasses. These gasses when exposed to water will turn to acid, hydrochloric acid for PVC and hydrofluoric for FEP. Unfortunately, the moisture in a person’s eyes or throat is enough to set off the chemical reaction and turn the gas into acid. Many high profile fires and the resulting deaths have proven that most casualties in a fire are caused by smoke and poisonous gasses not by the flame itself. So despite the ability to limit flame spread these chemicals are quickly falling out of favor. Consequently, there has been a push to move to materials that do not emit high levels of smoke and dangerous gasses when they do burn. Hence the move to LSZH compounds.
Why now? Many other cable types have already made the transition to LSZH compounds, but the category data cable market has lagged a bit. The quick answer for this lag is the electrical performance required by Category cables. In order to be flame retardant without the halogens, LSZH jacket compounds are forced to contain up to 50% non-flammable fillers. This results in less than optimum electrical performance that may be fine for basic electrical connections, but a significant obstacle for data cable design. Over time, strides in plastic compound technology and clever cable engineering have brought us to successful realization of the goal of a NEC/CEC CMX rated LSZH F/UTP patch cable family.