Demand for industrial cable is growing rapidly as factory automation escalates and capital spending rebounds. Making the right cable choice is becoming more complicated as world markets integrate and environmental codes tighten. Increasingly, technical capabilities—particularly in material formulations—create a broader array of choices.
What are the biggest potential pitfalls for design engineers when specifying cable? What's happening now is that you don't know the final destination of your machine, so you have to think globally. When you design a machine, you want to make sure it can be installed anywhere in the world.
Are there some particular issues that could be a problem?Absolutely. A lot of machinery comes from Europe to the United States. It often comes with cable to make it easier for the installer in the United States. Fifteen years ago that wasn't an issue. Today we live in a litigious society and the National Electrical Code (NEC) dictates what cable has to be used. So now when the product is shipped you must insure that the proper cable is also included or you will not be allowed to install the machinery. European and American viewpoints differ on halogens and flame retardancy. In Europe, they're more concerned about the halogen—components within the toxic smoke that result during a fire. In the United States, the concern is more of flame retardancy—preventing the fire from spreading. These are debatable issues as both American and European viewpoints each have their own separate agendas.
Is PVC still the dominant material used in cable jacketing?PVC is the first option because it is the most cost-effective. It's durable and has good electrical properties. If you're looking for other attributes, such as abrasion resistance, then you go into polyurethanes or thermoplastic elastomers (TPEs). Teflon can be used (fluorocarbon) for outstanding chemical resistance. PVC has come a long way with new technology. Are all PVC materials the same? Absolutely not. Some are good for cold impact. Some are good for oil resistance. Some are good for flexibility. Some are good for flame retardancy. PVC is a highly compounded material: 50 percent is typically base material, 25 percent additives, and 25 percent plasticizer. What's happening now is that chemists are working to keep costs down and develop a wide spectrum of new applications for PVC.
PVC must be a problem in Europe if halogen is an issue.Absolutely. PVC has chlorine and bromine which contain halogens. The future will mandate that cables be manufactured with halogen-free compounds. There are TPE blends now that are low smoke and low halogen but the cost is four times that conventional compounds—which no one wants to pay. The first company that arrives with a global halogen-free compound at a competitive price is going to be the big winner. We have a good head start on everybody in North America.
What about lead?Five years ago lead-free was a non-issue in North America. There were no concerns about lead-free cables. Now with Proposition 65 in California and the RoHS compliance, everything has changed. Lead-free is not an option. It's mandatory for new cable products.
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