眾所(suo)周知，當用(yong)(yong)電(dian)(dian)(dian)(dian)設(she)(she)備(bei)對(dui)人體心臟直接漏(lou)(lou)電(dian)(dian)(dian)(dian)大于10uA 時，會(hui)造成對(dui)患者的(de)微擊事(shi)故(gu)(gu)。而在(zai)一般通用(yong)(yong)建筑(zhu)中所(suo)采用(yong)(yong)的(de)RCD、ELCB等對(dui)地(di)漏(lou)(lou)電(dian)(dian)(dian)(dian)保護(hu)開關，其動(dong)作響應值是（如：30 mA），直流(liu)(liu)隔(ge)(ge)離電(dian)(dian)(dian)(dian)源(yuan)，遠遠不能滿足(zu)醫(yi)用(yong)(yong)領域的(de)需要。因此，現(xian)在(zai)國際上對(dui)醫(yi)用(yong)(yong)領域中的(de)手術室、ICU、CCU等重要場所(suo)通常采用(yong)(yong)局部“中性點不接地(di)的(de)供電(dian)(dian)(dian)(dian)系統”（即“IT系統”或稱“隔(ge)(ge)離電(dian)(dian)(dian)(dian)源(yuan)系統”）供電(dian)(dian)(dian)(dian)。通過(guo)單相3KVA-10KVA的(de)醫(yi)用(yong)(yong)隔(ge)(ge)離電(dian)(dian)(dian)(dian)源(yuan)給(gei)這些場所(suo)供電(dian)(dian)(dian)(dian)，首先可(ke)以(yi)防止其它供電(dian)(dian)(dian)(dian)回(hui)路中的(de)漏(lou)(lou)電(dian)(dian)(dian)(dian)流(liu)(liu)通過(guo)接地(di)線竄入(ru)手術室、ICU、CCU的(de)醫(yi)用(yong)(yong)電(dian)(dian)(dian)(dian)氣(qi)設(she)(she)備(bei)上對(dui)患者的(de)安全構成威脅；另外，一旦隔(ge)(ge)離電(dian)(dian)(dian)(dian)源(yuan)上所(suo)接的(de)負載（如各種醫(yi)用(yong)(yong)電(dian)(dian)(dian)(dian)氣(qi)設(she)(she)備(bei)）出現(xian)對(dui)地(di)故(gu)(gu)障，因對(dui)地(di)不能構成回(hui)路，只能產生一個很小(xiao)的(de)容性漏(lou)(lou)電(dian)(dian)(dian)(dian)流(liu)(liu)，極大地(di)保護(hu)了患者免(mian)遭(zao)漏(lou)(lou)電(dian)(dian)(dian)(dian)流(liu)(liu)的(de)傷害。

醫用設(she)備開(kai)(kai)關(guan)電(dian)源中包括以(yi)下(xia)元器(qi)(qi)件：開(kai)(kai)關(guan)變壓(ya)器(qi)(qi)、輸出整(zheng)流(liu)(liu)等等。開(kai)(kai)關(guan)電(dian)源的(de)具(ju)體工作原理如下(xia)：交流(liu)(liu)電(dian)源輸入(ru)并經過整(zheng)流(liu)(liu)濾波(bo)之后(hou)轉換為直(zhi)(zhi)流(liu)(liu)電(dian)源，通過PWM信號控(kong)(kong)制開(kai)(kai)關(guan)管，將(jiang)轉換后(hou)的(de)直(zhi)(zhi)流(liu)(liu)電(dian)源直(zhi)(zhi)接加(jia)至開(kai)(kai)關(guan)變壓(ya)器(qi)(qi)的(de)初級(ji)上(shang)，隨后(hou)開(kai)(kai)關(guan)變壓(ya)器(qi)(qi)的(de)次級(ji)會感應出高(gao)頻電(dian)壓(ya)，再經過整(zheng)流(liu)(liu)淘波(bo)后(hou)供給(gei)負(fu)載(zai)，輸出部分利用定(ding)的(de)電(dian)路反饋(kui)給(gei)控(kong)(kong)制電(dian)路，對PWM的(de)占空比(bi)進(jin)行控(kong)(kong)制，以(yi)此來達到穩定(ding)輸出的(de)目的(de)。

降低了對(dui)地漏電(dian)流，故提高了防火安全性。隨著現代化電(dian)子(zi)電(dian)氣(qi)技術和(he)設(she)備(bei)在(zai)醫用場所的應用，醫院的醫生和(he)已被電(dian)子(zi)儀器(qi)和(he)電(dian)子(zi)設(she)備(bei)所籠罩。隔(ge)離(li)電(dian)源，遠(yuan)程參數設(she)置和(he)查詢(xun)通(tong)過系統，可根據(ju)要求遠(yuan)程調整和(he)設(she)置各(ge)IT配電(dian)系統中絕緣(yuan)監(jian)測儀的各(ge)類報警參數閾值，也可以任意(yi)查看這些(xie)報警參數值。參數包括(kuo)絕緣(yuan)報警值、負載電(dian)流報警值和(he)隔(ge)離(li)變壓(ya)器(qi)溫度報警值等。強制要求醫場所的供(gong)(gong)電(dian)系統必須保(bao)證(zheng)與電(dian)網隔(ge)離(li)!供(gong)(gong)電(dian)主機內置了隔(ge)離(li)供(gong)(gong)電(dian)模(mo)塊。將(jiang)電(dian)網與設(she)備(bei)完全隔(ge)離(li)，避免了設(she)備(bei)的漏電(dian)對(dui)患者或醫護人員(yuan)造成傷害(hai)。