电线电缆载流量(全)常用线缆规格(BV BLV BVR)截面m㎡最大直径铝A铜A2.53.91731.644.42247.564.92967.1107621191687817925101182813511.51563815013.221552170152827349517.538696212019431118015021539147018523.5666181024026.585723503