Extreme temperatures, both hot and cold, and cables aren’t the merriest of bedfellows; exposed to extreme heat, a standard cable will cease to function and, even worse, melt while freezing temperatures will put paid to the operational capability of a cable.
While not necessarily a worry in everyday life, there are some applications in which a cable being able to function in extreme temperatures is essential. Factories, cold storage units, blast furnaces – all are subject to the kind of temperatures that would render your average cable useless. Heat-resistant cables are also frequently deployed in public buildings, where essential fire alarm systems and lighting need to work should a fire break out.
What is the Solution?
Custom cable designers have come up with a number of different designs that ensure that a cable can work in extremely high temperatures.
The most common form of heat protection deployed in custom cables is the cable jacket. PVC is one of the most commonly used materials in cable jacketing and, although it can withstand high temperatures up to around 80°C, any higher than that and the jacket will begin to degrade.
A popular heat-resistant alternative to PVC is silicone, which can usually withstand temperatures between -50°C and 180°C. This makes it an ideal material for high and low temperature applications. If a fire breaks out, silicone forms a layer of insulation which ensures that the cable can continue working on a short term basis. Silicone is also a low emission material, making it a safe choice for systems that could potentially be exposed to fire. But what about applications where the temperature is even higher than 180°C? What kind of high-performance material would be able to operate in that kind of temperature? Well, you needn’t look further than your kitchen pans… PTFE – more commonly known by the brand name Teflon – is capable of operating in temperatures up to a staggering 250°C – as you’d probably expect from a material used in cooking utensils!
In addition to its ability to withstand extreme heat, PTFE is also resistant to damage from a wide range of liquids and fluids, as well as chemical corrosion. This makes it an ideal solution for laboratory applications.
Care also needs to be paid to the choice of conductor in the cable. When it comes to heat resistance, nickel is usually the first choice of a cable, able to work consistently in temperatures up to around 600°C. Heat-resistant cables can be built with a single conductor or, more likely, as a multicore cable. It is still possible to create multicore cables using nickel conductors and a steel or copper braid can offer further protection against damage and electromagnetic interference. For more information on heat resistant cables, contact Custom Designed Cables on 01204 658 784.