HELUKABEL, with U.S. operations based in Elgin, Ill., just announced it is upgrading the entire TOPSERV and TOPGEBER product portfolio from 80°C to 90°C UL styles. Servo and feedback cables with higher heat resistance benefit from a longer service life, making them preferred in motor environments. Tests confirm that the conductor insulation maintained excellent thermal stability at temperatures up to 90°C for over 30,000 hours.
According to Thomas Pikkemaat, business and drive technology product manager at the company’s Windsbach, Germany plant, HELUKABEL is the first European manufacturer to upgrade all of its relevant products to 90°C UL styles. And, he added, higher heat resistance offers numerous advantages to users.
“For many years, 80°C UL styles have been the market norm. Very few drive technology manufacturers currently offer servo and feedback cables with a 90°C UL style specification. From a technical perspective though, there are good reasons for doing this. In motor environments, temperatures frequently exceed 80°C. Take motor terminal boxes, for example, where conductors are often exposed to even higher temperatures,” said Pikkemaat.
HELUKABEL uses PVC and polyurethane (PUR) for the jacket and conductor insulation, he continued. PUR is a thermoplastic elastomer with major benefits, particularly in drag chain applications where continuous flexing and high abrasion resistance are paramount. Higher heat resistance, however, is primarily the result of technical improvements in conductor insulation materials. “These days, we use polypropylene (PP) materials with heat resistance of up to 110°C. This thermoplastic not only has long-term temperature stability, it also has a very low dielectric constant. This makes PP an excellent insulation material.
“Until about 2009, polyester (TPE-E) was considered the best-in-class for drag chain servo cables. Its outstanding mechanical properties and high heat resistance made it a winner. However, TPE-E has two serious drawbacks. First, moisture, particularly at high temperatures, damages the hydrolytically-sensitive plastic. Second, and this is critical, its high dielectric constant leads to high capacitance values that can cause problems over longer distances,” continued Pikkemaat.
HELUKABEL has been using polypropylene since 2005, he explained. In the beginning, company engineers dealt with the lower heat resistance simply because technical understanding was limited and the capabilities of available materials had a ceiling of 80°C. “The major benefits of its electrical properties continued to impress and this motivated us to look for ways to improve its heat resistance,” Pikkemaat explained. “Today, we use special PP materials that can be optimally processed and are heat-resistant up to 110°C, thanks to further developments in the field of plastics and enhanced manufacturing methods.”
The high-temperature cables are well-suited for continuous use in applications like machine tools, added Pikkemaat. Technicians at the Windsbach laboratory subjected the new servo and feedback cables to months of testing. “As a result of such a strenuous and lengthy test, HELUKABEL can confirm conductor insulation heat resistance of 90°C for over 30,000 hours,” he stated.
UL styles of servo and feedback cable were created especially for HELUKABEL in partnership with UL and apply to all HELUKABEL Group manufacturing facilities, he said. The TOPSERV and TOPGEBER assortment will be available in 90°C UL styles starting in November. The upgrade will be seamless and products will maintain the same part number. As HELUKABEL has been using these heat-resistant materials for many years, the cables are technically unchanged except for the jacket marking.