电气计算公式及数据表

常用电流计算公式1：纯电阻负荷0负荷的功率（W)负荷电流（A）I0220电源电压（V）2：感性负荷1870负荷的功率（W)负荷电流（A）I02200.85 （V）Cos 电压功率因数3：单相电动机负荷1710负荷的功率（W)负荷电流（A）I02200.880.89 （V）Cos 电压机械率功率因数4：三相电动机负荷513#负荷的功率（W)负荷电流（A）I21.46041.733800.880.893 （V）Cos 平方根电压机械率功率因数5：住宅总负荷电流计算Pjs000KcP住宅用电计算负荷（W）同期系数，0.40.6，电器所有家用电器功率总和（W）越此值越小，反之，此值越大1760Pjs 住宅用电计算负荷（W）Ijs0住宅用电谁计算电流（A）2200.8（V）Cos 电压功率因数0.80.9电线电缆母线的电阻计算公式1:导线的电阻值计算Ro000S导线的交流电阻导线材料的电阻率导线标称截面积（/km)（m/km)（m）RtR201a20(t-20)Rt温度t时的电阻（/km)R20温度为20时的电阻（/km)a20电阻的温度系数2:母线的电阻值计算1母线的电阻值 R00.18519103m/m5400541000.00018519rSr母线电导率导线面积mm2铜54、铝32按安全载流量选择导线截面 按安全载流量选择导线截面，应满足下式要求：K IeI rs式中Ie导线安全载流量（A)；K当不境温度、穿管敷设等因素，与标准情况不同时的修正系数，见表3-18Ijs线路计算电流（A），其中：Pjs用有功功率表示的计算负荷（KW）Sjs用视在功率表示的计算成本负荷（KVA）三相电路用有功功率表示的计算负荷（KW）PjsSjs150001510001500015Ijs25.60622.789 585.796 1.73213800.89 6581.7321380线路计算电流（A）3 ueCos 3 ue平方根电压功率因数平方根电压单相电路用有功功率表示的计算负荷（KW）PjsSjs00100000Ijs001762200.8220线路计算电流（A）ueCos ue电压功率因数电压电能表所测电量计算计算公式KTA、KTV实际使用的电流互感器和电压互感器的变化；KTAe、KTVe电能表铭牌上标注的电流互感器和电压互感器的变比；对于万用互感器接入直接接入的电能表，因其铭牌上没有标注电流互感器、电压互感器的额定变比，其KTAe=KTVe=1.没有标注计能器倍率的电能表，其Kj=1.Kj计能器倍率，即读数盘方框上标注的倍数K数值KTVKTA、（6000100）（2005）K240060401112400KTAeKTVe空调器容量的选择计算1：家庭用空调器容量的选择对于墙厚在24以上，层高在3.2M以下，室外环境温度不超过43时，按每平方米选用120140W为宜。例如15的房间选用18002100W，房间朝南取小值，更爱西或房顶、墙壁较薄以及层高大于3.2M的房间取大值。不同制冷量单位的换算WKcal/hBTU/hKJ/H国标千卡/每小时(旧国标）英国热量单位千焦/每小时（外国）10.85983.4123.61.16313.96834.18860.2930.25211.0550.2780.2390.94812：较大场所用空调器容量的选择Qk(qVX空调器的容量（KJ/h)空调容量裕量系数，房间所需房间的总房间总人数人体排热量短期K=1冷量，q=容积坐时X=432KJ/h长期K=1.051.1105143做动后X=1591KJ/h电路电压损失计算1:电压损失是指送电端电压主与受电端电压之差，即电损电压v送电端电压v受电端电压vUU1U20002:通常用其百分数表示，即电压压损失率U。基计算公式电损电压送电端电压v受电端电压vUU1U20000#1007500Ue线路额定电压3：负荷在末端的线路电压损失计算。U1R、XU2oI、Cos 末端接负荷的三相电路IXcosU1U2 IRIRsin I IRCos IXsin电压失量图图中，U1为变电所出口电压，即送电端电压；U2为负荷处的电压，即受电端电压（均对中性点电压而言，单位为KV).在工程计算中，允许略去（Ixsin-IRCos）部分（由此引起的误差不超过实际电压降的5），因此线路每相电压可按以下简化公式计算。PR +QXUX I(R Cos x sin)=3 U2用线电压计算公式PR +QXU1 3 I(R Cos x sin)=U2式中 UX U1 分别为相电压、线电压的电压损失（V）R、X 分别为每条导线的电阻值和电抗值（）Ue 线路祖额定线电压（KV)Cos 负荷的功率因数 P I 负荷电流（线电流，A）I=3Ue Cos P、Q 分别为三相负荷总有功功率（KW）、总无功功率（Kvar)电压损失率按下式计算PU(R Cos+x Sin)10 Ue2Cos 负荷的功率（W)负荷的功率（W)负荷的功率（W)负荷的功率（W)Pjs 住宅用电计算负荷（W）10001000当不境温度、穿管敷设等因素，与标准情况不同时的修正系数，见表3-18Kj1uQz)房内设备同房间设备时使用率 总发热量和利用率(KJ)电能表铭牌上标注的电流互感器和电压互感器的变比；对于万用互感器接入直接接入的电能表，因其铭牌上没有标注电流互感器、电压互感器的额定变比，其KTAe=KTVe=1.没有标注计能器倍率的电能表，其Kj=1.对于墙厚在24以上，层高在3.2M以下，室外环境温度不超过43时，按每平方米选用120140W为宜。例如15的房间选用18002100W，人体排热量坐时X=432KJ/h做动后X=1591KJ/h之积，u=00.6PR +QX 3 Ue图中，U1为变电所出口电压，即送电端电压；U2为负荷处的电压，即受电端电压（均对中性点电压而言，单位为KV).在工程计算中，允许略去（Ixsin-IRCos）部分（由此引起的误差不超过实际电压降的5），因此线路PR +QX 3 U2PR +QX UePR +QX U2各和荧光灯的耗电量、额定电流及功率因数表常用家用电器的耗电量、频定电流及功率因数表灯管灯管耗镇流器耗 总耗电量 额定电流 功率因数寿命不家用电器名称型号电量（W）电量（W）（W）（A）COS&小于（h)电视机YZ6RR64100.140.332000电冰箱YZ8RR84120.150.362000洗衣机YZ15RR157.522.50.330.315000电熨斗YZ20RR208280.350.365000电热毯YZ30RR308380.360.485000电吹风机YZ40RR408480.410.535000电热杯 异步电动机的功率和效率与负荷的关系电暖器负荷空载25%50%75%100%电烤箱功率因数0.20.50.770.850.89电饭煲效率00.780.850.880.875电炒锅Cos和 tg对应值表吊扇序号Cos tgCos tg电热水器11000.710.99184446音响设备20.990.14258060.71.024534吸尘器30.980.203111240.691.0494622抽油烟机40.970.250514040.681.0784709排气扇50.960.291716160.671.1084756空调器60.950.328718120.661.1384842导电金属线电阻率、导电率和电阻温度系数70.940.36319570.651.1694927线材80.930.395321340.641.201501290.920.42623040.631.2335057硬铝线100.910.455624300.621.2655141软铝线110.90.484425510.611.2995225铝合金线120.890.512427080.61.3345308硬铜线130.880.539828210.591.3685351软铜线140.870.566829320.581.4035433150.860.593430410.571.4415515160.850.617931470.561.4795557170.840.645932520.551.525638180.830.67233540.541.5595719190.820.69834550.531.65800200.810.72435540.521.6435840210.80.7536520.511.6865920220.790.776137490.51.7326000230.780.802338440.451.9846315240.770.828639390.42.296625250.760.855140320.352.6776931260.750.881941250.33.187232270.740.908942160.253.8677531280.730.936243070.24.9017828290.720.96354357D26Cos型功率因数的Cos值与偏转角a计算表序号Cos tgtgaa11000020.998.10.14230.07394.2330.925.80.48340.0251214.140.836.90.75080.390221.350.745.61.0210.530727.9560.653.11.3310.69234.6770.5601.7320.900342数学常数表功率（W）额定电流（A）功率因数（Cos）常数1000.510.650.70.92002.273.030.30.421200.911.090.50.6450010002.274.5412201000.090.4513505501.592.511/3001.3611n15006.81e60012002.735.451e23005001.362.271e100015004.556.8211/e750.380.9M=lge3000600013.6427.2711/M=ln101502000.851.140.70.9e4008002.13.90.9421202000.61.00.92400.20.93100030006.5150.70.910180/20r20a2010800/（m/km)（km/m)（1/)648000/290.0340.0043128.30.0350.0041132.80.0310.00422117.90.0560.0038517.60.0570.00393常用家用电器的耗电量、频定电流及功率因数表导电金属线电阻率、导电率和电阻温度系数数值lg3.1415926540.4971498736.2831853070.79817986812.566370611.0992098649.8696044010.9942997451.7724538510.2485749360.318309886-1.5028501271.1447298860.0587030212.7182818290.4342944827.3890560980.8685889641.6487212710.2171472410.367894412-1.5657055180.434294482-1.6377843112.3025850930.36221568923.140692631.36437635420.3010299961.4142135620.1505149981.7320508080.2385606273.162277660.557.29577951311.7581226323437.746770783.536273883206264.806255.3144251330.017453293-2.2148773620.000290888-4.4637241174.8481E-06-6.685574867数学常数表nn2n3n 3 nn/4 n21/n0000000111113.1240.785412481.41421.25996.2833.14160.539271.73211.44229.4257.06860.33333466421.587412.5712.5660.255251252.23611.7115.7119.6350.26362162.44951.817118.8528.2740.166677493432.64581.912921.9938.4850.142868645122.8284225.1350.2660.12598172932.080128.2763.6170.111111010010003.16232.154431.4278.540.11112113313.31662.22434.5695.0330.090911214417283.46412.289437.7113.10.083331316921973.60562.351340.84132.730.076921419627443.74712.410443.98153.940.071431522533753.8732.466247.12176.720.0666716256409642.519850.27201.060.06251728949134.12312.571353.41226.980.058821832458324.24262.620756.55254.470.055561936168594.35892.668459.69283.530.05263204008004.42712.714462.83314.160.052144192614.58262.758965.97346.360.0476222484106484.69042.08269.12380.130.0454523529121674.79582.843972.96415.480.0434824576138244.8992.884575.4452.390.04167256251562552.92478.54490.870.0426676175765.0992.962581.68530.930.0384627729196835.1926384.82572.560.0370428784219525.29153.036687.97615.750.0357129841243895.38523.072391.11660.520.0344830900270005.47723.107294.25706.860.0333331961297915.56783.141497.39754.770.03226321024327685.65693.1748100.5804.250.03125331089359375.74463.2075103.7855.30.0303341156393045.8313.2396106.8907.920.02941351225428755.91613.2711110962.110.028573612964665663.3019113.11017.90.02778371369506536.08283.3322116.21075.20.02703381444548726.16443.362119.41134.10.02632391521593196.2453.3912122.51194.60.02564401600640006.32463.42125.71256.60.025411681689216.40313.4482128.81320.30.02439421764740886.48073.476131.91385.30.02381431849795076.55743.5034135.11452.20.02326441936851846.63323.5303138.21520.50.02273452025911256.70323.5569141.41590.40.02222462116973366.78233.583144.51661.90.021744722091038236.85573.6088147.61734.90.021284823041105926.92823.6342150.81809.60.0208349240111764973.6593153.61885.70.020415025001250007.07113.684157.11963.50.025126011326517.14143.7084160.22042.80.019615227041406807.21113.7325163.42123.70.019235328091488777.28013.7563166.52206.20.018875429161574647.34853.7798169.72290.20.018525530251663757.41623.803172.82375.80.018185631361756167.48333.8259175.924630.017865732491851937.54983.8485179.12551.80.017545833641951127.61583.8709182.22642.10.017245934812053797.68113.893185.427340.016956036002160007.7463.9149188.52827.40.016676137212269817.81023.9365191.62922.50.016396238442383287.8743.9579194.83019.10.016136339692500477.93733.9791197.93117.30.0158764409626214484201.132170.015636542252746258.02634.0207204.23318.30.015386643562874968.1244.0412207.43421.20.015156744893007638.18544.0615210.53525.70.014936846243144328.24624.0817213.63631.70.014716947613285098.30664.1016216.83739.30.014497049003430008.36664.1213219.93848.50.014297150413579118.42614.1048223.13959.20.014087251843732488.48534.1602226.24071.50.013897353293890178.5444.1793229.34185.40.01377454764052248.60234.1983232.54300.80.013517556254218758.66034.2172235.64417.90.013337657764389768.71784.2358238.84536.50.013167759294565338.7754.2543241.94656.60.012997860844745528.83184.27272454778.40.012827962414930398.88824.2908248.24901.70.012668064005120008.94434.2089251.35026.50.012581656153144194.3267254.551530.012358267245513689.05544.3445257.6528.10.01228368895717879.11044.3621260.85410.60.012058470565927049.16524.3795263.95541.80.01198572256142159.21954.39682675674.50.011768673966360569.27364.414270.25808.80.011638775696585039.32744.431273.35944.70.011498877446814729.38084.448276.56082.10.011368979217049699.4344.4647279.66221.10.011249081007290009.48684.4814282.76361.70.011119182817535319.53944.4979285.96503.90.010999284647786889.59174.51442896647.60.010879386498043579.64374.5307292.26792.90.010759488368305849.69544.5468295.36939.80.010649590258573759.74684.5629298.57088.20.010539692168847369.7984.5789301.67238.20.010429794099126739.84894.5947304.77389.80.010319896049411929.89954.6104307.675430.01029998019702999.94494.62613117697.70.0101100100001000000104.4616314.278540.01直埋电缆安全载流（A)标称截面双芯三芯四芯（2铜芯铝芯铜芯铝芯铜芯铝芯1.51391392.52216221622164352635263526652395239523910886683627456161239210579101752516212214010513299351981481671251541155023717820615518914170286214250188233174953342502992242722041203822873432573472601504403303822873962971854313232404483361kv vv vlv型无铠装聚氯乙烯护套聚乙烯绝缘电缆的安全载流量（A)安全载流量（A)标称截面单芯二芯三芯四芯（2)铜芯铝芯铜芯铝芯铜芯铝芯铜芯铝芯11815121.52319162.5322426202216441313526292229226544144343829382910725560465240514016977479616953685325122102107839372927135162124124951138711589502041571551201401081441117025319519615117513517813695272214238182214165218168120356276273211247191252195150410316315242293225297228185465358332257314263240552425396306300636490400757589500886680620102578780013389341kv vv29、vlv29、VV30、VLV30、VV50、VLV50、VV59、VLV59、型无铠装聚氯乙烯护套聚乙烯绝缘电缆的安全载流量（A)标称截面单芯二芯三芯四芯（2)铜芯铝芯铜芯铝芯铜芯铝芯铜芯铝芯4362731233023645353930393010765860465240524016100778162715470542513510410681967394733516412612899114881199250205158160128144111149115702531951971521791381841419531123924018521716722617412035627627821525219426020115041031631924629222530123118546635933325734526624055142439230530063248640076458750088267762010327878001208931单片铜母线的允许载流量（A)母线尺寸交流直流宽厚253035402530354015321019718517021019718517020327525824222327525824222325334032029927634032029927630447544641838547544641838540462558754650662558755050640570065961556770566462057150586080975669787081876570550695589884077496090284577860611251056990912114510791010928806148013901300120015101420133012251006181017001590147018751760165015206081320124011601070134512651185109080816901590149013701755165015451420100820801955183016852180205019201770120826502490233021502950277025952390 本表中系母线立放时的数据。当母线平放且宽度60时，表中数据应乘以0.95，宽度60时应乘0.92扁钢允许载流量（A)母线尺寸 标称截面载流量重量宽厚（2)交流直流(Kg/m)20360651000.4725375801200.5930490941400.714031201251900.945031501552301.186031801852801.417032102153201.657532252303451.778032402453651.889032702754102.1210033003054602.3620480701150.63254100851400.793041201001650.944041601302201.265042001652701.576042401953251.887042802253752.28043202604302.519043602904802.8310044003255353.14255125951700.983051501152001.184052001452651.575052501803251.966053002153902.368054002805103.1410055003506403.936063602102.838064802753.778086402905.021001010003907.85橡皮绝缘电线明敷时的安全载流量（A）标称截面BLX、BLXF（铝芯）BX、BXF(铜芯）（2)25303540253035401211918161.5272523212.5272523213532302743532302745423835645423835585450451065605651857973671685797367110102958725110102958714513512511435138129119109180168155142501751631511382302151981817022020619017428526624622595265247229209345322298272120310289268245400374346316150360336311284470439406371185420392363332540504467427240510476441403660617570522聚氯乙烯绝缘电线明敷时的安全载流量（A）标称截面BLV（铝芯）BV、BVR(铜芯）（2)25303540253035401191716151.518161514242220182.52523211932292725432292725423336336423936335551474310595551467570645916807469631059890832510598908313812911910935130121112102170158147134501651541421302152011851707020519117716226524722920095250233216197325303281257120285266246225375350324296150325303281257430402371340185380355328300490458423387塑料绝缘软线明敷设时的安全载流量（A）标称截面单根单芯二根单芯三根单芯（2)25 30 35 40 25 30 35 40 25 30 35 40RV0.154.543.543.53332.5 2.52RV0.276.565.5 5.554.5443.533RV0.3987.5776.565.554.543.5RVV0.411109.5 8.5 8.5 7.576.565.554.5RVB0.51312119.5 9.5 8.587.576.565.5RVS0.8161514131312119.5987.57RFB11917161515141211111098RFS1.5242221181917161514131211橡皮绝缘电线穿钢管敷设时的安全载流量（A）标称截面二根单芯三根单芯四根单芯环境温度管径（）环境温度管径（）环境温度管径（）（2)25 30 35 40GDG25 30 35 40GDG25 30 35 40GDG1151412111520141312111520121110915201.52018171515201816151415201715141320252.52826242215202523211915202321191820254373432292025303028262025302825232025649454238202540403734202539363330202510686358532532565651472532534945412532BX 16868074682532717166603232696459543240BXF25113 10597893240939386793232908477714050（铜芯）35140 130 121 1103240114 114 105963240110 1029587405050175 163 151 1384050143 143 133 1215050137 128 118 1085070215 201 185 1705050180 180 166 1525050173 161 149 1367095260 243 224 20570219 219 203 18570210 196 181 16670120 300 280 259 23770252 252 233 21370245 229 211 19370150 340 317 294 26870310 289 268 24570280 261 242 22180185 385 359 333 30480355 331 307 28080320 299 276 25380橡皮绝缘电线穿硬塑料管时的安全载流量（A）标称截面二根单芯三根单芯四根单芯环境温度管径（）环境温度管径（）环境温度管径（）（2)25 30 35 4025 30 35 4025 30 35 4011312111015121110915111098151.51715141315161413121514131211202.52523211915222019171520181715214333028262030282523202624222022643403734203835323020343129262510595551462552484441254643393632BX 16767165603268635853326056514732BXF251009386793290847771328074696340（铜芯）35125 116 1089840110 102958740989184774050160 149 138 12640140 130 121 11050123 115 106975070195 182 168 15450175 163 151 13850155 144 134 1225095240 224 207 18950215 201 185 17065195 182 168 15465120 278 259 240 21965250 233 216 19765227 212 196 17980150 320 299 276 25365290 271 250 22965265 247 229 20980185 360 336 311 28480330 308 285 26180300 280 259 237100聚氯乙烯绝缘电线穿钢管敷设时的安全载流量（A）标称截面二根单芯三根单芯四根单芯环境温度管径（）环境温度管径（）环境温度管径（）（2)25 30 35 40GDG25 30 35 40GDG25 30 35 40GDG114131211151513121110151511109815151.51917181515151715141315151614131215152.526242220151524222018151522201917151543532302715153128262415152826242215206474340371520413835321520373432292025106560565120025575349452025504643392525BV 1682767064252573686357253265605651253225107 10092842532958882753232857973673240（铜芯）35133 124 115 1053240115 10799903240105989083325050165 154 142 1303250146 136 126 1154050130 121 112 102505070205 191 177 1625050183 171 158 1445050165 154 142 130505095250 233 216 1975050225 210 194 17750200 187 173 15870120 290 270 250 2295050260 243 224 20550230 215 198 18170150 330 308 285 2617050300 280 259 23770265 247 229 20970185 380 355 325 30070340 317 294 26870300 280 259 23780聚氯乙烯绝缘电线穿硬塑料管时的安全载流量（A）标称截面二根单芯三根单芯四根单芯环境温度管径（）环境温度管径（）环境温度管径（）（2)25 30 35 4025 30 35 4025 30 35 4011211109151110981510987151.51614131215151413121513121110152.52422201815211918161519171615204312826242028262422202523211820641383532203633312820322927252510565248442549454238254441383432BX 16726762563265605651325753494532BXF25958882753285797367327570645940（铜芯）35120 112 103944010598908340938680735050150 140 129 11840132 123 114 10450117 109 101926370185 172 160 14650167 156 144 13050148 138 128 1176395230 215 198 18150205 191 177 16265185 172 160 14675120 270 252 233 21365240 224 207 18965215 201 185 17275150 305 285 263 24165275 257 237 21765250 233 216 19775185 355 331 307 28080289 289 268 24580280 261 242 22190BVV型和BLVV型熟料护套线规格、结构尺寸及参考载流量表标称截面线芯结构绝缘护套厚度最大外径BVV型参考载流量 BLVV型参考载流量根数直径层厚（A)（A)（2)单双芯 三芯单芯双芯三芯单芯双芯三芯单芯111.130.60.70.84.14.16.7 4.39.5201613151.511.370.60.70.84.44.47.2 4.610.3252116192.511.760.60.70.84.84.87.8 511.534262226412.240.60.70.85.35.39.1 5.513.145382935512.50.80.816.3 6.310.76.715.751433339612.730.80.816.5 6.511.36.916.556473643871.20.811.27.9 7.913.68.319.4705946541071.330.811.28.4 8.414.58.820.785725566双芯三芯12101612221729233326362845355643BVV型和BLVV型熟料护套线规格、结构尺寸及参考载流量表BLVV型参考载流量（A)