低频电缆是指额定频率在400Hz及以下的电缆,主要用于航空航天、船舶、铁路、汽车等领域。IEC 60708:2005标准规定了低频电缆的技术要求,包括导体、绝缘、护套、电气性能、机械性能、防火性能等方面。
导体方面,要求采用铜或铜合金导体,符合IEC 60228标准。绝缘方面,要求采用聚烯烃绝缘材料,如聚乙烯、聚丙烯等,其介电常数应不大于2.5。护套方面,要求采用防潮聚烯烃材料,如聚氯乙烯、聚乙烯等,其厚度应符合标准要求。
电气性能方面,要求低频电缆的电阻、绝缘电阻、电容等指标应符合标准要求。机械性能方面,要求低频电缆的拉伸强度、弯曲半径、耐磨性等指标应符合标准要求。防火性能方面,要求低频电缆应符合相应的防火等级要求。
IEC 60708:2005标准还规定了低频电缆的试验方法,包括导体电阻测量、绝缘电阻测量、电容测量、拉伸强度测量、弯曲半径测量、耐磨性测量等试验。此外,标准还规定了低频电缆的标记要求,包括电缆型号、额定电压、制造商名称、生产日期等信息。
相关标准
- IEC 60228:2004 Conductors of insulated cables
- IEC 60245-1:1998 Rubber insulated cables - Rated voltages up to and including 450/750 V - Part 1: General requirements
- IEC 60332-1-2:2004 Tests on electric and optical fibre cables under fire conditions - Part 1-2: Test for vertical flame propagation for a single insulated wire or cable - Procedure for 1 kW pre-mixed flame
- IEC 60332-3-24:2009 Tests on electric and optical fibre cables under fire conditions - Part 3-24: Test for vertical flame spread of vertically-mounted bunched wires or cables - Category C
- IEC 60811-1-1:2012 Common test methods for insulating and sheathing materials of electric cables - Part 1-1: General application - Measurement of thickness and overall dimensions - Tests for determining the mechanical properties