電(dian)(dian)(dian)氣(qi)間(jian)(jian)(jian)(jian)隙是兩(liang)個導(dao)電(dian)(dian)(dian)零(ling)部件(jian)之(zhi)間(jian)(jian)(jian)(jian)或導(dao)電(dian)(dian)(dian)零(ling)部件(jian)與設(she)備防護界(jie)面之(zhi)間(jian)(jian)(jian)(jian)測得(de)的(de)最(zui)短空間(jian)(jian)(jian)(jian)距離(li),爬電(dian)(dian)(dian)距離(li)是沿絕緣表(biao)面測得(de)的(de)兩(liang)個導(dao)電(dian)(dian)(dian)零(ling)部件(jian)之(zhi)間(jian)(jian)(jian)(jian)或導(dao)電(dian)(dian)(dian)零(ling)部件(jian)與設(she)備防護界(jie)面之(zhi)間(jian)(jian)(jian)(jian)最(zui)短路(lu)徑(jing)。電源適配器的設計應使用戶可觸及的導電(dian)零部件與危險電(dian)壓有效隔離(li),滿(man)足標準中(zhong)對最(zui)小電(dian)氣間隙和爬電(dian)距(ju)離(li)的要求,以實現危險防護(hu)。
眾所周知電(dian)源(yuan)適(shi)配器(qi)通常直接連接電(dian)網電(dian)源(yuan)危(wei)險(xian)電(dian)壓(ya),產品目(mu)前(qian)趨(qu)向于便(bian)攜式的(de)小巧緊湊型的(de)設(she)計,常出(chu)現與(yu)危(wei)險(xian)電(dian)壓(ya)無隔(ge)(ge)離(li)(li)(li)(li)或(huo)者(zhe)有隔(ge)(ge)離(li)(li)(li)(li)措施,但(dan)隔(ge)(ge)離(li)(li)(li)(li)不充(chong)分的(de)情況(kuang),危(wei)險(xian)程(cheng)度(du)令人(ren)堪憂。合格的(de)產品設(she)計應(ying)(ying)加大(da)隔(ge)(ge)離(li)(li)(li)(li)帶的(de)隔(ge)(ge)離(li)(li)(li)(li)寬度(du),使(shi)其電(dian)氣間(jian)隙和(he)爬(pa)電(dian)距離(li)(li)(li)(li)測量值滿(man)足標準要(yao)求,如果因線路(lu)布局和(he)元件安(an)置的(de)空間(jian)限制無法(fa)有效的(de)留出(chu)安(an)全距離(li)(li)(li)(li),可采用增加溝槽(cao)或(huo)固體絕(jue)緣擋板的(de)方式隔(ge)(ge)離(li)(li)(li)(li)危(wei)險(xian)電(dian)壓(ya),但(dan)其隔(ge)(ge)離(li)(li)(li)(li)應(ying)(ying)充(chong)分。
需要注意,固(gu)(gu)(gu)體絕緣(yuan)擋板以及絕緣(yuan)附近影響距(ju)(ju)離(li)的(de)大型元器件應充(chong)分(fen)固(gu)(gu)(gu)定,避免在標準(zhun)要求的(de)施(shi)力(li)條件下(xia)松動,從而減小(xiao)電(dian)氣間隙和爬電(dian)距(ju)(ju)離(li)。大功率電(dian)源(yuan)適配(pei)器的(de)結構更為(wei)復雜,我們對(dui)危險電(dian)壓(ya)的(de)有(you)效隔(ge)離(li)應充(chong)分(fen)考慮,例(li)如(ru):電(dian)源(yuan)板金(jin)屬接地屏蔽(bi)層(ceng)的(de)位置;作(zuo)為(wei)信號或電(dian)壓(ya)傳輸(shu)的(de)引出線的(de)固(gu)(gu)(gu)定;金(jin)屬散熱片的(de)布(bu)置;可(ke)觸及的(de)外殼接縫(feng)到內部(bu)危險元件的(de)距(ju)(ju)離(li)等(deng)等(deng)。必要時要采用絕緣(yuan)擋板、絕緣(yuan)膠帶(dai)、絕緣(yuan)套管等(deng)措施(shi)有(you)效隔(ge)離(li)。