地勘院施工临时用电方案计算1.doc

施工临时用电方案计算书酒泉卫星发射中心生活基地二期八期幼儿园、C6#、D5#楼、二期十区13#、14#楼，建筑面积为20937.36，其中幼儿园建筑面积1909.1，C6#楼建筑面积2727.27，地上为2293.74，地下为433.52。D5#楼建筑面积2632.13，地上为2205.36，地下为426.77，13#楼建筑面积6834.43，地上为6405.07，地下为429.36。14#楼建筑面积6834.43，地上为6405.07，地下为429.36。本工程位于酒泉市，北临规划铁人路，南临规划肃北路，西临解放北路。本工程由酒泉华恒置业有限公司投资建设，甘肃省工业与民用建筑设计院设计，核工业武威工程勘察院勘察，酒泉市顺帆工程监理有限责任公司监理，酒泉广厦建业有限公司组织施工；由杨兴红担任项目经理，万会元担任技术负责人。一、编制依据办公建筑设计规范JGJ 67-2006商店建筑设计规范JGJ 48-88建筑设计防火规范GB50016-2006民用建筑电气设计规范JGJ16-2008供配电系统设计规范GB5002-2009低压配电设计规范GB50054-2011建筑物防雷设计规范GB50057-2010建筑照明设计规范GB50034-2004视频安防监控系统工程技术规范GB50395-2007有线电视系统工程技术规范GBJ50200-94综合布线系统工程设计规范GB50311-2007建筑电气工程施工质量验收规范GB50303-2002建筑电气制图标准GBT 50786-2012二、施工条件施工现场用电量统计表:-序号 机具名称 型号 安装功率(kW) 数量 合计功率(kW)1 塔式起重机 QTZ315 31.5 1 31.5 2 搅拌机 BS750 7.5 1 7.5 3 插入式振动器 ZX70 1.5 1 1.5 4 100m高扬水泵 20 1 20 5 高压贡灯 1 1 1 6 碘钨灯 1 2 2 7 钢筋调直机 GT6/8 5.5 1 5.5 8 钢筋切断机 QJ40-1 5.5 1 5.5 9 钢筋弯曲机 GW40 3 1 3 10 平板式振动器 ZB11 1.1 1 1.1 11 钢筋套丝机 GT3/9 7.5 1 7.5 12 木工圆锯 MJ104 3 1 3 13 真空吸水泵 改型泵I号 5.5 1 5.5 14 塔式起重机 QTZ315 31.5 1 31.5 15 搅拌机 BS750 7.5 1 7.5 16 插入式振动器 ZX70 1.5 1 1.5 17 100m高扬水泵 20 1 20 18 高压贡灯 1 1 1 19 碘钨灯 1 1 1 20 振动夯土机 HZD250 4 1 4 21 直流电焊机 10 1 10 22 交流电焊机 BX3-200-2 23.4 1 23.4 23 木工圆锯 MJ104 3 1 3 24 真空吸水泵 改型泵I号 5.5 1 5.5 25 塔式起重机 QTZ63 50 1 50 26 搅拌机 BS750 7.5 1 7.5 27 100m高扬水泵 20 1 20 28 高压贡灯 1 1 1 29 碘钨灯 1 1 1 30 钢筋调直机 GT6/8 5.5 1 5.5 31 钢筋切断机 QJ40-1 5.5 1 5.5 32 钢筋弯曲机 GW40 3 1 3 33 钢筋套丝机 GT3/9 7.5 1 7.5 34 交流电焊机 BX3-200-2 23.4 1 23.4 -三、设计内容和步骤1、现场勘探及初步设计:(1)本工程所在施工现场范围内无各种埋地管线。(2)现场采用380V低压供电，设一配电总箱，内有计量设备，采用TN-S系统供电。(3)根据施工现场用电设备布置情况，采用导线穿钢管埋地敷设，布置位置及线路走向参见临时配电系统图及现场平面图，采用三级配电，两级防护。(4)按照JGJ46-2005规定制定施工组织设计，接地电阻R4。2、确定用电负荷:(1)、塔式起重机Kx = 0.2 Cos = 0.6 tg = 1.33将Jc =40%统一换算到Jc1 =25%的额定容量Pn = 31.5kWPe = n(Jc/Jc1)1/2Pn = 1(0.4/0.25)1/231.5 = 60.72 kWPjs = KxPe =0.260.72 = 12.14kWQjs = Pjs tg=12.141.33 = 16.19 kvar(2)、搅拌机Kx = 0.3 Cos = 0.7 tg = 1.02Pjs = 0.37.5 = 2.25 kWQjs = Pjs tg=2.251.02 = 2.3 kvar(3)、插入式振动器Kx = 0.3 Cos = 0.7 tg = 1.02Pjs = 0.31.5 = 0.45 kWQjs = Pjs tg=0.451.02 = 0.46 kvar(4)、100m高扬程水泵Kx = 0.75 Cos = 0.8 tg = 0.75Pjs = 0.7520 = 15 kWQjs = Pjs tg=150.75 = 11.25 kvar(5)、高压贡灯Kx = 0.1 Cos = 0.1 tg = 9.95Pjs = 0.11 = 0.1 kWQjs = Pjs tg=0.19.95 = 0.99 kvar(6)、碘钨灯Kx = 0.1 Cos = 0.1 tg = 9.95Pjs = 0.12 = 0.2 kWQjs = Pjs tg=0.29.95 = 1.99 kvar(7)、钢筋调直机Kx = 0.3 Cos = 0.7 tg = 1.02Pjs = 0.35.5 = 1.65 kWQjs = Pjs tg=1.651.02 = 1.68 kvar(8)、钢筋切断机Kx = 0.3 Cos = 0.7 tg = 1.02Pjs = 0.35.5 = 1.65 kWQjs = Pjs tg=1.651.02 = 1.68 kvar(9)、钢筋弯曲机Kx = 0.3 Cos = 0.7 tg = 1.02Pjs = 0.33 = 0.9 kWQjs = Pjs tg=0.91.02 = 0.92 kvar(10)、平板式振动器Kx = 0.3 Cos = 0.7 tg = 1.02Pjs = 0.31.1 = 0.33 kWQjs = Pjs tg=0.331.02 = 0.34 kvar(11)、钢筋套丝机Kx = 0.7 Cos = 0.4 tg = 2.29Pjs = 0.77.5 = 5.25 kWQjs = Pjs tg=5.252.29 = 12.03 kvar(12)、木工圆锯Kx = 0.3 Cos = 0.6 tg = 1.33Pjs = 0.33 = 0.9 kWQjs = Pjs tg=0.91.33 = 1.2 kvar(13)、真空吸水泵Kx = 0.75 Cos = 0.8 tg = 0.75Pjs = 0.755.5 = 4.12 kWQjs = Pjs tg=4.120.75 = 3.09 kvar (14)、塔式起重机Kx = 0.2 Cos = 0.6 tg = 1.33将Jc =40%统一换算到Jc1 =25%的额定容量Pn = 31.5kWPe = n(Jc/Jc1)1/2Pn = 1(0.4/0.25)1/231.5 = 60.72 kWPjs = KxPe =0.260.72 = 12.14kWQjs = Pjs tg=12.141.33 = 16.19 kvar(15)、搅拌机Kx = 0.75 Cos = 0.85 tg = 0.62Pjs = 0.757.5 = 5.62 kWQjs = Pjs tg=5.620.62 = 3.49 kvar(16)、插入式振动器Kx = 0.3 Cos = 0.7 tg = 1.02Pjs = 0.31.5 = 0.45 kWQjs = Pjs tg=0.451.02 = 0.46 kvar(17)、100m高扬程水泵Kx = 0.75 Cos = 0.8 tg = 0.75Pjs = 0.7520 = 15 kWQjs = Pjs tg=150.75 = 11.25 kvar(18)、高压贡灯Kx = 0.1 Cos = 0.1 tg = 9.95Pjs = 0.11 = 0.1 kWQjs = Pjs tg=0.19.95 = 0.99 kvar(19)、碘钨灯Kx = 0.1 Cos = 0.1 tg = 9.95Pjs = 0.11 = 0.1 kWQjs = Pjs tg=0.19.95 = 0.99 kvar(20)、振动夯土机Kx = 0.5 Cos = 0.6 tg = 1.33Pjs = 0.54 = 2 kWQjs = Pjs tg=21.33 = 2.67 kvar(21)、直流电焊机Kx = 0.35 Cos = 0.6 tg = 1.33将Jc =50%统一换算到Jc1 =100%的额定容量Pn = Sn Cos = 100.6=6kWPe = n(Jc/Jc1)1/2Pn = 1(0.5/1)1/26 = 4.24 kWPjs = KxPe =0.354.24 = 1.48kWQjs = Pjs tg=1.481.33 = 1.98 kvar(22)、交流电焊机Kx = 0.35 Cos = 0.4 tg = 2.29将Jc =50%统一换算到Jc1 =100%的额定容量Pn = Sn Cos = 23.40.4=9.36kWPe = n(Jc/Jc1)1/2Pn = 1(0.5/1)1/29.36 = 6.62 kWPjs = KxPe =0.356.62 = 2.32kWQjs = Pjs tg=2.322.29 = 5.31 kvar(23)、木工圆锯Kx = 0.3 Cos = 0.6 tg = 1.33Pjs = 0.33 = 0.9 kWQjs = Pjs tg=0.91.33 = 1.2 kvar(24)、真空吸水泵Kx = 0.75 Cos = 0.8 tg = 0.75Pjs = 0.755.5 = 4.12 kWQjs = Pjs tg=4.120.75 = 3.09 kvar (25)、塔式起重机Kx = 0.2 Cos = 0.6 tg = 1.33将Jc =40%统一换算到Jc1 =25%的额定容量Pn = 50kWPe = n(Jc/Jc1)1/2Pn = 1(0.4/0.25)1/250 = 62.72 kWPjs = KxPe =0.262.72 = 12.54kWQjs = Pjs tg=12.541.33 = 16.69 kvar(26)、搅拌机Kx = 0.75 Cos = 0.85 tg = 0.62Pjs = 0.757.5 = 5.62 kWQjs = Pjs tg=5.620.62 = 3.49 kvar(27)、100m高扬程水泵Kx = 0.75 Cos = 0.8 tg = 0.75Pjs = 0.7520 = 15 kWQjs = Pjs tg=150.75 = 11.25 kvar(28)、高压贡灯Kx = 0.1 Cos = 0.1 tg = 9.95Pjs = 0.11 = 0.1 kWQjs = Pjs tg=0.19.95 = 0.99 kvar(29)、碘钨灯Kx = 0.1 Cos = 0.1 tg = 9.95Pjs = 0.11 = 0.1 kWQjs = Pjs tg=0.19.95 = 0.99 kvar(30)、钢筋调直机Kx = 0.3 Cos = 0.7 tg = 1.02Pjs = 0.35.5 = 1.65 kWQjs = Pjs tg=1.651.02 = 1.68 kvar(31)、钢筋切断机Kx = 0.3 Cos = 0.7 tg = 1.02Pjs = 0.35.5 = 1.65 kWQjs = Pjs tg=1.651.02 = 1.68 kvar(32)、钢筋弯曲机Kx = 0.3 Cos = 0.7 tg = 1.02Pjs = 0.33 = 0.9 kWQjs = Pjs tg=0.91.02 = 0.92 kvar(33)、钢筋套丝机Kx = 0.7 Cos = 0.4 tg = 2.29Pjs = 0.77.5 = 5.25 kWQjs = Pjs tg=5.252.29 = 12.03 kvar(34)、交流电焊机Kx = 0.35 Cos = 0.4 tg = 2.29将Jc =50%统一换算到Jc1 =100%的额定容量Pn = Sn Cos = 23.40.4=9.36kWPe = n(Jc/Jc1)1/2Pn = 1(0.5/1)1/29.36 = 6.62 kWPjs = KxPe =0.356.62 = 2.32kWQjs = Pjs tg=2.322.29 = 5.31 kvar (35)总的计算负荷计算，总箱同期系数取 Kx = 0.9总的有功功率Pjs = KxPjs =0.9(12.14+2.25+0.45+15+0.1+0.2+1.65+1.65+0.9+0.33+5.25+0.9+4.12+12.14+5.62+0.45+15+0.1+0.1+2+1.48+2.32+0.9+4.12+12.54+5.62+15+0.1+0.1+1.65+1.65+0.9+5.25+2.32) = 167.482 kW总的无功功率Qjs = KxQjs =0.9(16.19+2.3+0.46+11.25+0.99+1.99+1.68+1.68+0.92+0.34+12.03+1.2+3.09+16.19+3.49+0.46+11.25+0.99+0.99+2.67+1.98+5.31+1.2+3.09+16.69+3.49+11.25+0.99+0.99+1.68+1.68+0.92+12.03+5.31) = 225.046 kvar总的视在功率Sjs = ( Pjs2+Qjs2 )1/2 = (167.6482+225.0462)1/2 = 280.627 kVA总的计算电流计算Ijs = Sjs/(1.732Ue) = 280.627/(1.7320.38) = 426.381 A3、1号干线线路上导线截面及分配箱、开关箱内电气设备选择:在选择前应对照平面图和系统图先由用电设备至开关箱计算，再由开关箱至分配箱计算，选择导线及开关设备。分配箱至开关箱，开关箱至用电设备的导线敷设采用铜橡皮绝缘导线穿硬塑料管敷设，由于这部分距离较短，因此不考虑电压降，只按安全载流量选择导线截面。(1)、塔式起重机开关箱至塔式起重机导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.6 tg = 1.33Ijs = Kx Pe /(1.732Ue Cos) = 160.72/(1.7320.380.6) = 153.75Aii)选择导线选择BX-450+125 ，穿硬塑料管时其安全载流量为156.52A。iii)选择电气设备选择开关箱内开关为DZ10-250/3 ，其脱扣器整定电流值为Ir = 200A。漏电保护器为 DZ10L-250/3。(2)、搅拌机开关箱至搅拌机导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.7 tg = 1.02Ijs = KxPe /(1.732Ue Cos) = 17.5/(1.7320.380.7) = 16.28Aii)选择导线选择BX-41.5+11 ，穿硬塑料管时其安全载流量为17.89A。iii)选择电气设备选择开关箱内开关为DZ5-50/3 ，其脱扣器整定电流值为Ir = 40A。漏电保护器为 DZ10L-100/3。(3)、插入式振动器开关箱至插入式振动器导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.7 tg = 1.02Ijs = KxPe /(1.732Ue Cos) = 11.5/(1.7320.380.7) = 3.26Aii)选择导线选择BX-41+10.75 ，穿硬塑料管时其安全载流量为13.42A。iii)选择电气设备选择开关箱内开关为DZ5-20/3 ，其脱扣器整定电流值为Ir = 16A。漏电保护器为 DZ10L-100/3。(4)、100m高扬程水泵开关箱至100m高扬程水泵导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.8 tg = 0.75Ijs = KxPe /(1.732Ue Cos) = 120/(1.7320.380.8) = 37.98Aii)选择导线选择BX-46+14 ，穿硬塑料管时其安全载流量为42.49A。iii)选择电气设备选择开关箱内开关为DZ5-50/3 ，其脱扣器整定电流值为Ir = 40A。漏电保护器为 DZ10L-100/3。(5)、高压贡灯开关箱至高压贡灯导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.1 tg = 9.95Ijs = KxPe /(1.732Ue Cos) = 11/(1.7320.380.1) = 15.19Aii)选择导线选择BX-41.5+11 ，穿硬塑料管时其安全载流量为17.89A。iii)选择电气设备选择开关箱内开关为DZ5-20/3 ，其脱扣器整定电流值为Ir = 16A。漏电保护器为 DZ10L-100/3。(6)、碘钨灯开关箱至碘钨灯导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.1 tg = 9.95Ijs = KxPe /(1.732Ue Cos) = 11/(1.7320.380.1) = 15.19Aii)选择导线选择BX-41.5+11 ，穿硬塑料管时其安全载流量为17.89A。iii)选择电气设备由于开关控制2台机械，开关的电流为Ir=15.192.00(台数)= 30.39 A。选择开关箱内开关为DZ5-50/3 ，其脱扣器整定电流值为Ir = 40A。漏电保护器为 DZ10L-100/3。(7)、钢筋调直机开关箱至钢筋调直机导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.7 tg = 1.02Ijs = KxPe /(1.732Ue Cos) = 15.5/(1.7320.380.7) = 11.94Aii)选择导线选择BX-41+10.75 ，穿硬塑料管时其安全载流量为13.42A。iii)选择电气设备选择开关箱内开关为Hk1-15/3 ，熔断器RC1A-15其最大熔体电流为 IRD = 15A，可根据实际电流的2.5倍选择额定电流较小的熔丝，漏电保护器为 DZ10L-100/3。(8)、钢筋切断机开关箱至钢筋切断机导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.7 tg = 1.02Ijs = KxPe /(1.732Ue Cos) = 15.5/(1.7320.380.7) = 11.94Aii)选择导线选择BX-41+10.75 ，穿硬塑料管时其安全载流量为13.42A。iii)选择电气设备选择开关箱内开关为Hk1-15/3 ，熔断器RC1A-15其最大熔体电流为 IRD = 15A，可根据实际电流的2.5倍选择额定电流较小的熔丝，漏电保护器为 DZ10L-100/3。(9)、钢筋弯曲机开关箱至钢筋弯曲机导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.7 tg = 1.02Ijs = KxPe /(1.732Ue Cos) = 13/(1.7320.380.7) = 6.51Aii)选择导线选择BX-41+10.75 ，穿硬塑料管时其安全载流量为13.42A。iii)选择电气设备选择开关箱内开关为Hk1-15/3 ，熔断器RC1A-10其最大熔体电流为 IRD = 10A，可根据实际电流的2.5倍选择额定电流较小的熔丝，漏电保护器为 DZ10L-100/3。(10)、平板式振动器开关箱至平板式振动器导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.7 tg = 1.02Ijs = KxPe /(1.732Ue Cos) = 11.1/(1.7320.380.7) = 2.39Aii)选择导线选择BX-41+10.75 ，穿硬塑料管时其安全载流量为13.42A。iii)选择电气设备选择开关箱内开关为DZ5-20/3 ，其脱扣器整定电流值为Ir = 16A。漏电保护器为 DZ10L-100/3。(11)、钢筋套丝机开关箱至钢筋套丝机导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.4 tg = 2.29Ijs = KxPe /(1.732Ue Cos) = 17.5/(1.7320.380.4) = 28.49Aii)选择导线选择BX-44+12.5 ，穿硬塑料管时其安全载流量为33.54A。iii)选择电气设备选择开关箱内开关为DZ5-50/3 ，其脱扣器整定电流值为Ir = 40A。漏电保护器为 DZ10L-100/3。(12)、木工圆锯开关箱至木工圆锯导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.6 tg = 1.33Ijs = KxPe /(1.732Ue Cos) = 13/(1.7320.380.6) = 7.6Aii)选择导线选择BX-41+10.75 ，穿硬塑料管时其安全载流量为13.42A。iii)选择电气设备选择开关箱内开关为Hk1-15/3 ，熔断器RC1A-10其最大熔体电流为 IRD = 10A，可根据实际电流的2.5倍选择额定电流较小的熔丝，漏电保护器为 DZ10L-100/3。(13)、真空吸水泵开关箱至真空吸水泵导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.8 tg = 0.75Ijs = KxPe /(1.732Ue Cos) = 15.5/(1.7320.380.8) = 10.45Aii)选择导线选择BX-41+10.75 ，穿硬塑料管时其安全载流量为13.42A。iii)选择电气设备选择开关箱内开关为DZ5-20/3 ，其脱扣器整定电流值为Ir = 16A。漏电保护器为 DZ10L-100/3。 (14)、1号分箱至第1组电机(塔式起重机、搅拌机、插入式振动器、100m高扬程水泵、高压贡灯、碘钨灯、钢筋调直机、钢筋切断机、钢筋弯曲机、平板式振动器、钢筋套丝机、木工圆锯、真空吸水泵)的开关箱的导线截面及分配箱内开关的选择i) 计算电流塔式起重机Kx = 0.2 Cos= 0.6 tg= 1.33Ijs = KxPe 台数/(1.732Ue Cos) = 0.260.721/(1.7320.380.6) = 30.75A搅拌机Kx = 0.3 Cos= 0.7 tg= 1.02Ijs = KxPe 台数/(1.732Ue Cos) = 0.37.51/(1.7320.380.7) = 4.88A插入式振动器Kx = 0.3 Cos= 0.7 tg= 1.02Ijs = KxPe 台数/(1.732Ue Cos) = 0.31.51/(1.7320.380.7) = 0.98A100m高扬程水泵Kx = 0.75 Cos= 0.8 tg= 0.75Ijs = KxPe 台数/(1.732Ue Cos) = 0.75201/(1.7320.380.8) = 28.49A高压贡灯Kx = 0.1 Cos= 0.1 tg= 9.95Ijs = KxPe 台数/(1.732Ue Cos) = 0.111/(1.7320.380.1) = 1.52A碘钨灯Kx = 0.1 Cos= 0.1 tg= 9.95Ijs = KxPe 台数/(1.732Ue Cos) = 0.112/(1.7320.380.1) = 3.04A钢筋调直机Kx = 0.3 Cos= 0.7 tg= 1.02Ijs = KxPe 台数/(1.732Ue Cos) = 0.35.51/(1.7320.380.7) = 3.58A钢筋切断机Kx = 0.3 Cos= 0.7 tg= 1.02Ijs = KxPe 台数/(1.732Ue Cos) = 0.35.51/(1.7320.380.7) = 3.58A钢筋弯曲机Kx = 0.3 Cos= 0.7 tg= 1.02Ijs = KxPe 台数/(1.732Ue Cos) = 0.331/(1.7320.380.7) = 1.95A平板式振动器Kx = 0.3 Cos= 0.7 tg= 1.02Ijs = KxPe 台数/(1.732Ue Cos) = 0.31.11/(1.7320.380.7) = 0.72A钢筋套丝机Kx = 0.7 Cos= 0.4 tg= 2.29Ijs = KxPe 台数/(1.732Ue Cos) = 0.77.51/(1.7320.380.4) = 19.94A木工圆锯Kx = 0.3 Cos= 0.6 tg= 1.33Ijs = KxPe 台数/(1.732Ue Cos) = 0.331/(1.7320.380.6) = 2.28A真空吸水泵Kx = 0.75 Cos= 0.8 tg= 0.75Ijs = KxPe 台数/(1.732Ue Cos) = 0.755.51/(1.7320.380.8) = 7.83A (15)1号分箱进线及进线开关的选择i)计算电流Kx = 0.7，Cos = 0.9Ijs = KxPe /(1.732Ue Cos) = 0.7122.1/(1.7320.380.9) = 144.29A该分箱下最大组线电流Ijs=169.13A两者中取大值Ijs=169.13Aii)选择导线选择BX-450+125 ，穿焊接钢管时其安全载流量为137.74A。iii)选择电气设备选择分配箱进线开关为DZ10-250/3 ，其脱扣器整定电流值为Ir = 200A。(16)1号干线导线截面及出线开关的选择i) 计算电流：按导线安全载流量：Kx = 0.7 ，Cos = 0.9Ijs = KxPe/(1.732UeCos) = 0.7122.1/(1.7320.380.9) = 144.29 A该干线下最大的分配箱电流Ijs=169.13A选择的电流Ijs=169.13A按允许电压降：S = Kx(PL)/CU = 0.7122.125/(775) = 5.55 mm2选择BX-450+125 ，穿焊接钢管时其安全载流量为137.74A。ii)选择出线开关1号干线出线开关选择DZ10-250/3 ，其脱扣器整定电流值为Ir =200A。4、2号干线线路上导线截面及分配箱、开关箱内电气设备选择:在选择前应对照平面图和系统图先由用电设备至开关箱计算，再由开关箱至分配箱计算，选择导线及开关设备。分配箱至开关箱，开关箱至用电设备的导线敷设采用铜橡皮绝缘导线穿硬塑料管敷设，由于这部分距离较短，因此不考虑电压降，只按安全载流量选择导线截面。(1)、塔式起重机开关箱至塔式起重机导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.6 tg = 1.33Ijs = Kx Pe /(1.732Ue Cos) = 160.72/(1.7320.380.6) = 153.75Aii)选择导线选择BX-450+125 ，穿硬塑料管时其安全载流量为156.52A。iii)选择电气设备选择开关箱内开关为DZ10-250/3 ，其脱扣器整定电流值为Ir = 200A。漏电保护器为 DZ10L-250/3。(2)、搅拌机开关箱至搅拌机导线截面及开关箱内电气设备选择（开关箱以下机械启动后需要系数取1）:i)计算电流Kx = 1 Cos = 0.85 tg = 0.62Ijs = KxPe /(1.732Ue Cos) = 17.5/