直流電動機試驗前的一般檢查
直流電動機試驗前的一般檢查:
a)對電動機的裝(zhuang)配質量進行一般性檢(jian)查(如緊(jin)固(gu)件是(shi)否(fou)擰緊(jin)、轉子轉動(dong)是(shi)否(fou)靈(ling)活);刷(shua)握(wo)(wo)應(ying)牢固(gu)而地固(gu)定在刷(shua)架(jia)上,刷(shua)握(wo)(wo)下(xia)緣應(ying)與換(huan)(huan)向(xiang)(xiang)器(qi)(qi)表(biao)(biao)面(mian)平(ping)行,各刷(shua)握(wo)(wo)之(zhi)間(jian)的距離(li)應(ying)相(xiang)等;電刷(shua)應(ying)能自由地在刷(shua)握(wo)(wo)內(nei)上下(xia)移(yi)動(dong),但(dan)也不能太松;電刷(shua)表(biao)(biao)面(mian)與換(huan)(huan)向(xiang)(xiang)器(qi)(qi)應(ying)很(hen)好吻合;電刷(shua)頂端的彈簧壓力應(ying)調節(jie)適當;換(huan)(huan)向(xiang)(xiang)器(qi)(qi)表(biao)(biao)面(mian)應(ying)清潔光滑,換(huan)(huan)向(xiang)(xiang)片(pian)間(jian)的云母片(pian)不得高出換(huan)(huan)向(xiang)(xiang)器(qi)(qi)表(biao)(biao)面(mian),凹(ao)進深度為1-1.5㎜;檢(jian)查電動(dong)機(ji)的出線是(shi)否(fou)正確;
b)用塞(sai)規在(zai)電樞圓周上檢查各磁(ci)極(ji)下的氣隙,每次(ci)在(zai)電動機軸向(xiang)兩端測量。空氣隙的MAX容許偏差值不應超過其(qi)算(suan)術平均(jun)值的±10%。
對修理后的直流電動機通常進行下列試驗:
a)檢查電(dian)動(dong)機(ji)(ji)繞(rao)組(zu)(zu)(zu)的極性(xing)及其聯接的正(zheng)確性(xing);檢查主(zhu)磁(ci)極與(yu)換(huan)向(xiang)極繞(rao)組(zu)(zu)(zu)聯接的正(zheng)確性(xing);檢查串勵(li)對(dui)并(bing)勵(li)繞(rao)組(zu)(zu)(zu)之(zhi)間(或各并(bing)勵(li)繞(rao)組(zu)(zu)(zu)之(zhi)間)聯接的正(zheng)確性(xing);繞(rao)組(zu)(zu)(zu)對(dui)機(ji)(ji)殼(ke)及繞(rao)組(zu)(zu)(zu)相互(hu)(hu)間絕(jue)(jue)緣(yuan)(yuan)電(dian)阻的測定(ding)(ding)、測量(liang)時,除了測量(liang)各繞(rao)組(zu)(zu)(zu)對(dui)機(ji)(ji)殼(ke)及其相互(hu)(hu)間的絕(jue)(jue)緣(yuan)(yuan)電(dian)阻以(yi)外,還測量(liang)電(dian)樞繞(rao)組(zu)(zu)(zu)的鋼絲(si)箍(gu)對(dui)換(huan)向(xiang)器(qi)之(zhi)間、換(huan)向(xiang)器(qi)緊圈對(dui)換(huan)向(xiang)片之(zhi)間、刷架對(dui)機(ji)(ji)殼(ke)之(zhi)間(此時電(dian)刷應提(ti)起)的絕(jue)(jue)緣(yuan)(yuan)電(dian)阻。絕(jue)(jue)緣(yuan)(yuan)電(dian)阻值不應低于下式(shi)(shi)計(ji)算的數值,即(ji)R=UN/(1000+PN/100),式(shi)(shi)中(zhong)R—絕(jue)(jue)緣(yuan)(yuan)電(dian)阻(MΩ);UN—電(dian)動(dong)機(ji)(ji)額定(ding)(ding)電(dian)壓(V);PN—電(dian)動(dong)機(ji)(ji)額定(ding)(ding)功率(KW);
b)測量(liang)繞(rao)(rao)(rao)組的(de)直流電(dian)(dian)阻,采用雙臂電(dian)(dian)橋。測量(liang)應進(jin)行三次,取(qu)其(qi)算術平均(jun)值(zhi),同時用溫度計測量(liang)環境溫度;在電(dian)(dian)動機各(ge)繞(rao)(rao)(rao)組正確(que)接線的(de)情況下,為保證電(dian)(dian)動機運行性能良(liang)好,電(dian)(dian)動機的(de)電(dian)(dian)刷必(bi)須放(fang)在幾何中性線位置(zhi)上;如有(you)更換繞(rao)(rao)(rao)組,檢修換向器等情況,或(huo)對繞(rao)(rao)(rao)組絕(jue)緣(yuan)有(you)懷(huai)疑(yi)時,將各(ge)繞(rao)(rao)(rao)組和換向器對機殼作耐(nai)壓試驗(yan),及(ji)各(ge)繞(rao)(rao)(rao)組之間作耐(nai)壓試驗(yan);
c)如果上(shang)述各(ge)項試驗合格(ge),對電動機即可通(tong)電進行(xing)空載試驗;
d)一般檢修后的直流(liu)電(dian)動機可不進行負載試驗。