Wind Turbine Tray Cable2010-12-14
According to NPFA 70 of National Electrical Code(R), NEC, WTTC means the cable which can be installed in cable tray or wire way of wind driven generator. In the authentication system of UL, WTTC is involved under ZGZN product type, the evaluation base requirement is Subject 2277- Outline of Investigation for Flexible Motor Supply Cable and Wind Turbine Tray Cable:
＊Rating——WTTC voltage class is 1000V, temperature class scope is 90-200℃(dry environment) and choice 90℃moisture resistance temperature class. WTTC evaluation also covers sunlight resistance (weather-proof) class used under the environment exposure to the sun; oil resistance aging class applicable for oily environment; smoke limit class to judge cable smoke release status under fire; or special class criterion in -40 ℃.
＊Structure——WTTC includes two-chip or multichip insulated conductor and jacket and the conductor is from 18 AWG to 1000 kcmil. The general insulated conductor wire rod is linetype THHN or THWN. WTTC should conform to UL 1277 Standard for Electrical Power and Control Tray Cables with Optional Optical-Fiber Members.
＊Performance——Unless otherwise specified, WTTC should conform to performance requirement of UL 1277. Suppose that the insulated conductor used for cable has been testified to meet the corresponding standard, the finished cable should pass the following tests:
◇ Structure measurement
◇ Physical property test of jacket- unaged and oven aged Spark test according to wire regulation of UL 44
◇ for voltage class 1000/2000V
◇ Dielectric voltage-withstand test according to wire regulation of UL 44 for voltage class 1000/2000V
◇ Vertical tray flam test without smoke measurement Cold bend test with full cable
◇ Jacket heat deformation test (only applicable for
◇ thermoplastic material and XL jacket)
◇ Jacket heat shock test (only applicable for thermoplastic material)
◇ Durability of ink printing Other applicable test items of choice rating:
◇ Oil resistance aging test with oil resistance aging characteristic cable
◇ Sunlight resistance test with sunlight resistance characteristic cable
◇ Vertical tray fire propagation and smoke release test with smoke limit class cable
◇ Low temperature cold impact test used for -40℃cable Refer to “Table 1” for evaluation outline of UL for wind turbine tray cable. Please contact UL for more information.