一(yi)旦隔離(li)(li)(li)電(dian)(dian)(dian)(dian)源上所接的(de)各種醫(yi)用(yong)設(she)備出(chu)(chu)現對(dui)(dui)地(di)(di)故障(zhang)，因其對(dui)(dui)地(di)(di)不(bu)(bu)能構(gou)成回(hui)路，所以只(zhi)能產(chan)生(sheng)一(yi)個(ge)(ge)很小的(de)容性漏電(dian)(dian)(dian)(dian)流，極(ji)大地(di)(di)保(bao)護了(le)患者免遭漏電(dian)(dian)(dian)(dian)流的(de)傷害。一(yi)般(ban)供(gong)電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)網是(shi)(shi)以大地(di)(di)作(zuo)為參(can)(can)考(kao)電(dian)(dian)(dian)(dian)位(wei)，相線中的(de)電(dian)(dian)(dian)(dian)流可(ke)以通過(guo)任何未絕緣的(de)通道，對(dui)(dui)地(di)(di)構(gou)成回(hui)路，這是(shi)(shi)的(de)根本(ben)原(yuan)(yuan)因。隔離(li)(li)(li)供(gong)電(dian)(dian)(dian)(dian)是(shi)(shi)采(cai)用(yong)隔離(li)(li)(li)變(bian)壓器(qi)供(gong)電(dian)(dian)(dian)(dian)，電(dian)(dian)(dian)(dian)源經(jing)隔離(li)(li)(li)變(bian)壓器(qi)隔離(li)(li)(li)后，it系統生(sheng)產(chan)廠(chang)家(jia)，原(yuan)(yuan)電(dian)(dian)(dian)(dian)網中的(de)地(di)(di)已不(bu)(bu)再是(shi)(shi)參(can)(can)考(kao)電(dian)(dian)(dian)(dian)位(wei)。IT系統內部一(yi)旦出(chu)(chu)現個(ge)(ge)對(dui)(dui)地(di)(di)漏電(dian)(dian)(dian)(dian)故障(zhang)，不(bu)(bu)會導致系統斷路器(qi)或(huo)熔斷器(qi)動作(zuo)，因而保(bao)證(zheng)了(le)電(dian)(dian)(dian)(dian)源供(gong)電(dian)(dian)(dian)(dian)的(de)可(ke)靠(kao)性（負載出(chu)(chu)現漏電(dian)(dian)(dian)(dian)的(de)情(qing)況下不(bu)(bu)斷電(dian)(dian)(dian)(dian)）。

有些醫(yi)院設(she)(she)(she)備(bei)(bei)用于維持患(huan)者(zhe)的生(sheng)命，一旦設(she)(she)(she)備(bei)(bei)停電(dian)(dian)(dian)(dian)，也會對患(huan)者(zhe)的生(sheng)命構(gou)成威(wei)脅。因此，對于醫(yi)院這一特殊場所的電(dian)(dian)(dian)(dian)氣(qi)(qi)設(she)(she)(she)計(ji)，應(ying)嚴格按(an)照和規(gui)范要求，采用IT系(xi)統供電(dian)(dian)(dian)(dian)。在(zai)醫(yi)院的特殊環境里，電(dian)(dian)(dian)(dian)流對患(huan)者(zhe)生(sheng)命安全構(gou)成了潛在(zai)威(wei)脅。傳統的TN (接(jie)地)供電(dian)(dian)(dian)(dian)系(xi)統無法防(fang)范微安級(ji)漏電(dian)(dian)(dian)(dian)電(dian)(dian)(dian)(dian)流對人員可能(neng)出現(xian)的微電(dian)(dian)(dian)(dian)生(sheng)命危害(hai)。在(zai)電(dian)(dian)(dian)(dian)氣(qi)(qi)上必須保(bao)證(zheng)(zheng)醫(yi)用設(she)(she)(she)備(bei)(bei)電(dian)(dian)(dian)(dian)源系(xi)統的可靠(kao)性，既保(bao)證(zheng)(zheng)設(she)(she)(she)備(bei)(bei)對患(huan)者(zhe)的直(zhi)接(jie)測電(dian)(dian)(dian)(dian)流不(bu)超過10μA，同時又要保(bao)證(zheng)(zheng)在(zai)漏電(dian)(dian)(dian)(dian)流或過電(dian)(dian)(dian)(dian)流狀態(tai)下，有不(bu)間斷供電(dian)(dian)(dian)(dian)的可靠(kao)保(bao)證(zheng)(zheng)。

如果出現單相(xiang)接(jie)地故(gu)障，對地漏電(dian)(dian)(dian)(dian)流(liu)(liu)只能經過(guo)(guo)系(xi)(xi)統(tong)泄(xie)露電(dian)(dian)(dian)(dian)容對系(xi)(xi)統(tong)相(xiang)線構(gou)成回路，而(er)系(xi)(xi)統(tong)泄(xie)露電(dian)(dian)(dian)(dian)容引(yin)起的(de)(de)容抗總是遠(yuan)遠(yuan)大于TN系(xi)(xi)統(tong)中的(de)(de)接(jie)地電(dian)(dian)(dian)(dian)阻，因此IT系(xi)(xi)統(tong)中的(de)(de)漏電(dian)(dian)(dian)(dian)流(liu)(liu)非常的(de)(de)小(xiao)，斷(duan)路器不(bu)會因接(jie)地電(dian)(dian)(dian)(dian)流(liu)(liu)的(de)(de)存在而(er)引(yin)起過(guo)(guo)電(dian)(dian)(dian)(dian)流(liu)(liu)動作，從而(er)保(bao)證(zheng)(zheng)系(xi)(xi)統(tong)帶(dai)故(gu)障運行。在電(dian)(dian)(dian)(dian)氣(qi)上必(bi)須保(bao)證(zheng)(zheng)醫用設(she)(she)備電(dian)(dian)(dian)(dian)源(yuan)系(xi)(xi)統(tong)的(de)(de)可靠性，既(ji)保(bao)證(zheng)(zheng)設(she)(she)備對患(huan)者的(de)(de)直(zhi)接(jie)測電(dian)(dian)(dian)(dian)流(liu)(liu)不(bu)超過(guo)(guo)10μA，同時又要保(bao)證(zheng)(zheng)在漏電(dian)(dian)(dian)(dian)流(liu)(liu)或(huo)過(guo)(guo)電(dian)(dian)(dian)(dian)流(liu)(liu)狀態(tai)下，有不(bu)間斷(duan)供電(dian)(dian)(dian)(dian)的(de)(de)可靠保(bao)證(zheng)(zheng)。在0類(lei)和(he)1類(lei)醫院場(chang)所(suo)，由(you)于無醫院設(she)(she)備使用，或(huo)相(xiang)關設(she)(she)備僅使用在人體些非致命部位，所(suo)以可使用普通(tong)建欽(qin)物的(de)(de)電(dian)(dian)(dian)(dian)漂源(yuan)各和(he)漏電(dian)(dian)(dian)(dian)保(bao)護措施。