家庭裝修布電線選購中的導體外徑探討
返回列表來源:湘江電纜發布日期 2018-04-16 08:50瀏覽:- 加入收藏
隨著我國國民經濟(ji)的發(fa)展(zhan),城市建(jian)設(she)越來(lai)越繁華(hua),其裝修用(yong)布(bu)電線產(chan)品(pin)市場需要旺盛(sheng),布(bu)電線產(chan)品(pin)屬于CCC強制認證產(chan)品(pin),國內(nei)各(ge)廠家在生(sheng)產(chan)時(shi)執行國家標(biao)準GB/T 5023-2008,生(sheng)產(chan)企(qi)業每年(nian)必須將(jiang)產(chan)品(pin)送檢(jian)到指定(ding)的權威檢(jian)測機構進行性能(neng)檢(jian)測,憑借檢(jian)驗合格報告(gao)以及現場審核獲取生(sheng)產(chan)許(xu)可(ke)證,如產(chan)品(pin)未取得生(sheng)產(chan)許(xu)可(ke)證而生(sheng)產(chan),屬違法行為。
通過走入市(shi)場進(jin)行調查,消(xiao)費者(zhe)在市(shi)場比對(dui)同一(yi)規格產品(pin)時,往往會發現這(zhe)樣的(de)問題,不(bu)同廠(chang)家(jia)的(de)布(bu)電線產品(pin)導體外徑為什(shen)么不(bu)一(yi)致,例(li)(li)如,以6mm2布(bu)電線用(yong)導體為例(li)(li),有的(de)廠(chang)家(jia)導體外徑為2.76 mm,有的(de)廠(chang)家(jia)導體外徑2.90mm甚至(zhi)更(geng)大,這(zhe)樣就(jiu)給消(xiao)費者(zhe)造成一(yi)種(zhong)假象(xiang),導體外徑越大,布(bu)電線越好,其實不(bu)然,針對(dui)這(zhe)個(ge)情(qing)況,下(xia)面(mian)從三(san)個(ge)方面(mian)談一(yi)下(xia)這(zhe)個(ge)問題:
1標準
舊版(ban)布(bu)電(dian)(dian)線(xian)(xian)國家標(biao)(biao)(biao)(biao)準(zhun)GB/T 5023-1985版(ban)中(zhong)嚴格規(gui)定(ding)了(le)導(dao)(dao)體(ti)(ti)(ti)的(de)外(wai)徑、直流電(dian)(dian)阻性(xing)能(neng)指標(biao)(biao)(biao)(biao),明確規(gui)定(ding)了(le)6mm2布(bu)電(dian)(dian)線(xian)(xian)用導(dao)(dao)體(ti)(ti)(ti)外(wai)經為2.76mm;在1997年,新(xin)的(de)布(bu)電(dian)(dian)線(xian)(xian)國家標(biao)(biao)(biao)(biao)準(zhun)GB/T 5023-1997版(ban)中(zhong),規(gui)定(ding)了(le)導(dao)(dao)體(ti)(ti)(ti)性(xing)能(neng)指標(biao)(biao)(biao)(biao)必(bi)須符合GB/T 3956(電(dian)(dian)纜導(dao)(dao)體(ti)(ti)(ti)國家標(biao)(biao)(biao)(biao)準(zhun))要(yao)求(qiu),而(er)在GB/T 3956標(biao)(biao)(biao)(biao)準(zhun)中(zhong)要(yao)求(qiu)6mm2布(bu)電(dian)(dian)線(xian)(xian)用導(dao)(dao)體(ti)(ti)(ti)外(wai)徑最大(da)值不得超(chao)(chao)過2.90mm;新(xin)版(ban)布(bu)電(dian)(dian)線(xian)(xian)國家標(biao)(biao)(biao)(biao)準(zhun)GB/T 5023-2008版(ban)中(zhong),對(dui)于導(dao)(dao)體(ti)(ti)(ti)外(wai)徑的(de)要(yao)求(qiu)與GB/T 5023-1997要(yao)求(qiu)相同,即6mm2布(bu)電(dian)(dian)線(xian)(xian)用導(dao)(dao)體(ti)(ti)(ti)外(wai)徑最大(da)值不得超(chao)(chao)過2.90mm。(目前(qian)GB/T 5023-1997是最新(xin)的(de)有(you)效的(de)布(bu)電(dian)(dian)線(xian)(xian)國家標(biao)(biao)(biao)(biao)準(zhun),已經替(ti)換了(le)GB/T 5023-1985、GB/T 5023-1997兩版(ban)標(biao)(biao)(biao)(biao)準(zhun))
2工藝
GB/T 5023-1985標(biao)準(zhun)中(zhong)(zhong)嚴格(ge)(ge)規定導(dao)(dao)體(ti)(ti)(ti)(ti)(ti)外(wai)徑(jing)(jing)(2.76mm)到GB/T 5023-1997以及GB/T 5023-2008版中(zhong)(zhong)只(zhi)是(shi)要求(qiu)導(dao)(dao)體(ti)(ti)(ti)(ti)(ti)外(wai)徑(jing)(jing)最大(da)值(2.90mm),這(zhe)其中(zhong)(zhong)主要是(shi)因(yin)為:上世(shi)紀八十年代,當時原(yuan)材料銅(tong)材冶煉(lian)(lian)生(sheng)產工(gong)藝水平(ping)不高(gao),銅(tong)桿中(zhong)(zhong)雜質較多,造(zao)成導(dao)(dao)體(ti)(ti)(ti)(ti)(ti)電阻偏(pian)大(da),故為了保證布電線的(de)(de)直流(liu)電阻,國家標(biao)準(zhun)嚴格(ge)(ge)要求(qiu)布電線導(dao)(dao)體(ti)(ti)(ti)(ti)(ti)外(wai)徑(jing)(jing),而(er)隨著銅(tong)材冶煉(lian)(lian)水平(ping)的(de)(de)不斷發展和導(dao)(dao)體(ti)(ti)(ti)(ti)(ti)加工(gong)工(gong)藝的(de)(de)提高(gao),銅(tong)材中(zhong)(zhong)的(de)(de)雜質含(han)量越來越小,目前(qian)行業內,各廠保證導(dao)(dao)體(ti)(ti)(ti)(ti)(ti)直流(liu)電阻符合(he)要求(qiu)的(de)(de)情況下(xia),生(sheng)產的(de)(de)導(dao)(dao)體(ti)(ti)(ti)(ti)(ti)外(wai)徑(jing)(jing)也(ye)(ye)(ye)有了相應的(de)(de)減小,銅(tong)材消耗(hao)量也(ye)(ye)(ye)有相應減小,這(zhe)也(ye)(ye)(ye)是(shi)國家標(biao)準(zhun)中(zhong)(zhong)只(zhi)規定了導(dao)(dao)體(ti)(ti)(ti)(ti)(ti)的(de)(de)最大(da)外(wai)徑(jing)(jing),而(er)不明(ming)確規定導(dao)(dao)體(ti)(ti)(ti)(ti)(ti)具體(ti)(ti)(ti)(ti)(ti)數值的(de)(de)原(yuan)因(yin)。
3、根(gen)據導體直(zhi)流電阻公式:
R=ρ×L/S
R為導體直流電阻;
ρ為(wei)(wei)在環境溫(wen)度為(wei)(wei)20°時(shi)導(dao)體電阻率
L為導體單位長度
S為導(dao)體截面積
根據公式,為了保證布電(dian)(dian)(dian)線的(de)載流(liu)量滿足要求,其導(dao)體(ti)的(de)直流(liu)電(dian)(dian)(dian)阻必須符合標準要求,而直流(liu)電(dian)(dian)(dian)阻根據公式,R受(shou)ρ和S的(de)影(ying)響,S與導(dao)體(ti)直徑有(you)關(guan)系,ρ和銅(tong)材的(de)純度(du)有(you)關(guan)系,在導(dao)體(ti)直流(liu)電(dian)(dian)(dian)阻一定時(shi),當導(dao)體(ti)外(wai)徑較(jiao)大時(shi),則ρ增大,銅(tong)材的(de)純度(du)下降(jiang),如(ru)果導(dao)體(ti)外(wai)徑較(jiao)小(xiao),則ρ減小(xiao),銅(tong)材的(de)純度(du)提高。
根據(ju)以上三(san)個方面的(de)分析,消費(fei)者在(zai)(zai)選用(yong)布(bu)(bu)電(dian)線(xian)產品(pin)(pin)時(shi),布(bu)(bu)電(dian)線(xian)導體外徑的(de)大小是(shi)不(bu)能(neng)作為(wei)唯一的(de)標準來判(pan)斷產品(pin)(pin)時(shi)否合格,即在(zai)(zai)布(bu)(bu)電(dian)線(xian)規格選定時(shi),導體外徑越大反而不(bu)好,所(suo)以應(ying)根據(ju)導體直流電(dian)阻以及機械性能(neng)來判(pan)斷產品(pin)(pin)質量。