1、光端機供電(dian)及安(an)裝環境

一(yi)(yi)般發(fa)射(she)機(ji)(ji)(ji)(ji)(ji)由于(yu)安(an)(an)裝(zhuang)(zhuang)(zhuang)位置跟隨(sui)前端(duan)(duan)視頻采(cai)集(ji)(ji)設(she)備(bei)，所以(yi)安(an)(an)裝(zhuang)(zhuang)(zhuang)位置都比較(jiao)(jiao)分散(san)(san)，需(xu)要(yao)配(pei)(pei)獨立的(de)(de)機(ji)(ji)(ji)(ji)(ji)殼(ke)(ke)給其供(gong)電(dian)(dian)。在(zai)安(an)(an)防(fang)監控供(gong)電(dian)(dian)方(fang)面通常(chang)(chang)有兩種方(fang)式(shi)(shi)(shi)：中(zhong)(zhong)(zhong)(zhong)心集(ji)(ji)中(zhong)(zhong)(zhong)(zhong)供(gong)電(dian)(dian)和(he)本地供(gong)電(dian)(dian)，由于(yu)采(cai)用(yong)(yong)光(guang)(guang)(guang)(guang)端(duan)(duan)機(ji)(ji)(ji)(ji)(ji)傳輸的(de)(de)現場(chang)，前后端(duan)(duan)距(ju)離(li)都較(jiao)(jiao)遠，所以(yi)較(jiao)(jiao)少使用(yong)(yong)集(ji)(ji)中(zhong)(zhong)(zhong)(zhong)供(gong)電(dian)(dian)方(fang)式(shi)(shi)(shi)。接(jie)收機(ji)(ji)(ji)(ji)(ji)一(yi)(yi)般都位于(yu)監控中(zhong)(zhong)(zhong)(zhong)心的(de)(de)機(ji)(ji)(ji)(ji)(ji)房(fang)內，不(bu)(bu)像(xiang)發(fa)射(she)機(ji)(ji)(ji)(ji)(ji)那么分散(san)(san)，在(zai)供(gong)電(dian)(dian)方(fang)式(shi)(shi)(shi)上(shang)如(ru)果跟前端(duan)(duan)的(de)(de)發(fa)射(she)機(ji)(ji)(ji)(ji)(ji)一(yi)(yi)樣采(cai)用(yong)(yong)機(ji)(ji)(ji)(ji)(ji)殼(ke)(ke)電(dian)(dian)源供(gong)電(dian)(dian)的(de)(de)話，會占用(yong)(yong)機(ji)(ji)(ji)(ji)(ji)房(fang)大(da)量空(kong)間，顯得(de)雜亂無(wu)章，無(wu)法統(tong)一(yi)(yi)管理(li)。因(yin)此中(zhong)(zhong)(zhong)(zhong)心接(jie)收機(ji)(ji)(ji)(ji)(ji)供(gong)電(dian)(dian)可(ke)以(yi)采(cai)用(yong)(yong)插(cha)卡式(shi)(shi)(shi)機(ji)(ji)(ji)(ji)(ji)箱供(gong)電(dian)(dian)，不(bu)(bu)要(yao)把插(cha)槽全插(cha)滿，可(ke)以(yi)每隔(ge)幾個插(cha)槽空(kong)開一(yi)(yi)個，有利于(yu)光(guang)(guang)(guang)(guang)端(duan)(duan)機(ji)(ji)(ji)(ji)(ji)散(san)(san)熱(re)。需(xu)要(yao)注意的(de)(de)是光(guang)(guang)(guang)(guang)端(duan)(duan)機(ji)(ji)(ji)(ji)(ji)的(de)(de)激(ji)光(guang)(guang)(guang)(guang)器組件和(he)光(guang)(guang)(guang)(guang)電(dian)(dian)轉換模塊(kuai)最(zui)忌(ji)瞬時(shi)(shi)(shi)脈沖電(dian)(dian)流的(de)(de)沖擊(ji)，因(yin)此不(bu)(bu)宜頻繁開關機(ji)(ji)(ji)(ji)(ji)。前端(duan)(duan)發(fa)射(she)機(ji)(ji)(ji)(ji)(ji)多安(an)(an)裝(zhuang)(zhuang)(zhuang)在(zai)前端(duan)(duan)配(pei)(pei)電(dian)(dian)箱中(zhong)(zhong)(zhong)(zhong)，要(yao)注意做好(hao)(hao)配(pei)(pei)電(dian)(dian)箱的(de)(de)防(fang)塵防(fang)水，在(zai)配(pei)(pei)電(dian)(dian)箱塞和(he)較(jiao)(jiao)滿時(shi)(shi)(shi)為了利于(yu)光(guang)(guang)(guang)(guang)端(duan)(duan)機(ji)(ji)(ji)(ji)(ji)散(san)(san)熱(re)就(jiu)要(yao)考(kao)慮帶(dai)風扇的(de)(de)配(pei)(pei)電(dian)(dian)箱。監控中(zhong)(zhong)(zhong)(zhong)心的(de)(de)機(ji)(ji)(ji)(ji)(ji)房(fang)要(yao)保持環(huan)境整潔(jie)，經常(chang)(chang)注意清(qing)理(li)，不(bu)(bu)要(yao)有結塵，最(zui)好(hao)(hao)是在(zai)機(ji)(ji)(ji)(ji)(ji)房(fang)裝(zhuang)(zhuang)(zhuang)修(xiu)好(hao)(hao)后再將設(she)備(bei)裝(zhuang)(zhuang)(zhuang)入(ru)機(ji)(ji)(ji)(ji)(ji)房(fang)，如(ru)遇(yu)機(ji)(ji)(ji)(ji)(ji)房(fang)裝(zhuang)(zhuang)(zhuang)修(xiu)改造，要(yao)及時(shi)(shi)(shi)清(qing)理(li)干凈。機(ji)(ji)(ji)(ji)(ji)房(fang)內一(yi)(yi)般會有很多設(she)備(bei)集(ji)(ji)中(zhong)(zhong)(zhong)(zhong)安(an)(an)裝(zhuang)(zhuang)(zhuang)在(zai)機(ji)(ji)(ji)(ji)(ji)柜(ju)中(zhong)(zhong)(zhong)(zhong)，設(she)備(bei)發(fa)熱(re)量很大(da)，在(zai)通風散(san)(san)熱(re)條件又差時(shi)(shi)(shi)，最(zui)好(hao)(hao)安(an)(an)裝(zhuang)(zhuang)(zhuang)空(kong)調(diao)系統(tong)以(yi)保證光(guang)(guang)(guang)(guang)端(duan)(duan)機(ji)(ji)(ji)(ji)(ji)正常(chang)(chang)工作。安(an)(an)裝(zhuang)(zhuang)(zhuang)光(guang)(guang)(guang)(guang)端(duan)(duan)機(ji)(ji)(ji)(ji)(ji)時(shi)(shi)(shi)要(yao)做好(hao)(hao)現場(chang)的(de)(de)防(fang)護措(cuo)施，防(fang)潮、防(fang)水、防(fang)塵，同時(shi)(shi)(shi)注意現場(chang)的(de)(de)實際(ji)操作，必須配(pei)(pei)備(bei)合適的(de)(de)光(guang)(guang)(guang)(guang)纖(xian)使用(yong)(yong)，不(bu)(bu)能使用(yong)(yong)殘(can)缺(que)故障(zhang)的(de)(de)光(guang)(guang)(guang)(guang)纖(xian)，如(ru)果不(bu)(bu)匹(pi)配(pei)(pei)，則會嚴重影響(xiang)光(guang)(guang)(guang)(guang)端(duan)(duan)機(ji)(ji)(ji)(ji)(ji)傳輸質(zhi)量，涉及光(guang)(guang)(guang)(guang)纜熔(rong)接(jie)時(shi)(shi)(shi)，也要(yao)注意測(ce)量光(guang)(guang)(guang)(guang)纜的(de)(de)光(guang)(guang)(guang)(guang)衰減或損(sun)耗在(zai)有效值范圍(wei)內。

2、光端機防雷

光(guang)端(duan)(duan)機(ji)特別是(shi)作(zuo)為前端(duan)(duan)設(she)備的(de)發射機(ji)通(tong)常安裝于室外的(de)設(she)備箱中(zhong)，現(xian)場環境相當惡劣(lie)，防(fang)雷(lei)就(jiu)顯得(de)異常重要(yao)(yao)，防(fang)雷(lei)措施(shi)的(de)優劣(lie)直接決定(ding)了光(guang)端(duan)(duan)機(ji)發生故障的(de)幾率。雷(lei)電的(de)破壞方式主要(yao)(yao)分為直擊雷(lei)、感應雷(lei)和(he)地電位反擊三種形式，對(dui)光(guang)端(duan)(duan)機(ji)而言影響最嚴(yan)重的(de)主要(yao)(yao)是(shi)地電位反擊。

所(suo)謂地(di)電(dian)(dian)(dian)(dian)(dian)位反(fan)擊(ji)是當避雷(lei)針等接(jie)(jie)(jie)(jie)閃器(qi)將(jiang)直擊(ji)雷(lei)強大(da)的(de)(de)(de)(de)雷(lei)電(dian)(dian)(dian)(dian)(dian)流經(jing)過引下(xia)線和(he)接(jie)(jie)(jie)(jie)地(di)體(ti)泄(xie)入大(da)地(di)時，在引下(xia)線，接(jie)(jie)(jie)(jie)地(di)體(ti)以及(ji)與其(qi)(qi)相(xiang)連的(de)(de)(de)(de)金屬物體(ti)上(shang)會(hui)(hui)產生相(xiang)當高的(de)(de)(de)(de)瞬間電(dian)(dian)(dian)(dian)(dian)壓(ya)，這個高電(dian)(dian)(dian)(dian)(dian)壓(ya)會(hui)(hui)對離他們很(hen)近(jin)但(dan)是又(you)沒(mei)有(you)直接(jie)(jie)(jie)(jie)接(jie)(jie)(jie)(jie)觸的(de)(de)(de)(de)金屬物體(ti)、線纜(lan)等電(dian)(dian)(dian)(dian)(dian)子設(she)(she)備(bei)(bei)之間產生巨大(da)的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)位差，這個電(dian)(dian)(dian)(dian)(dian)位差引起的(de)(de)(de)(de)電(dian)(dian)(dian)(dian)(dian)擊(ji)就是地(di)電(dian)(dian)(dian)(dian)(dian)位反(fan)擊(ji)。地(di)電(dian)(dian)(dian)(dian)(dian)位反(fan)擊(ji)是通過以下(xia)形式(shi)對光端機(ji)造成(cheng)損(sun)壞(huai)的(de)(de)(de)(de)：當雷(lei)電(dian)(dian)(dian)(dian)(dian)流泄(xie)入大(da)地(di)時，接(jie)(jie)(jie)(jie)地(di)網的(de)(de)(de)(de)地(di)電(dian)(dian)(dian)(dian)(dian)位會(hui)(hui)在數微(wei)秒(miao)之內被抬高到數萬(wan)(wan)或數十(shi)萬(wan)(wan)伏。高度破壞(huai)性的(de)(de)(de)(de)雷(lei)電(dian)(dian)(dian)(dian)(dian)流將(jiang)從(cong)各種設(she)(she)備(bei)(bei)的(de)(de)(de)(de)接(jie)(jie)(jie)(jie)地(di)部(bu)分流向這些設(she)(she)備(bei)(bei)，或者通過擊(ji)穿大(da)地(di)絕(jue)緣而流向其(qi)(qi)它附近(jin)設(she)(she)備(bei)(bei)，最終造成(cheng)設(she)(she)備(bei)(bei)的(de)(de)(de)(de)破壞(huai)或損(sun)害，損(sun)壞(huai)的(de)(de)(de)(de)部(bu)分主要有(you)：機(ji)殼電(dian)(dian)(dian)(dian)(dian)源(yuan)的(de)(de)(de)(de)PCB板上(shang)電(dian)(dian)(dian)(dian)(dian)子元器(qi)件、視頻接(jie)(jie)(jie)(jie)口處芯片(pian)及(ji)其(qi)(qi)相(xiang)關電(dian)(dian)(dian)(dian)(dian)子元器(qi)件、音頻及(ji)數據端口處芯片(pian)。

雖然(ran)雷(lei)(lei)電(dian)(dian)(dian)的(de)(de)破壞形(xing)式多種(zhong)多樣，但還是(shi)可以(yi)通(tong)過(guo)(guo)采(cai)取科學的(de)(de)防(fang)(fang)護(hu)措施來降(jiang)低(di)光端(duan)(duan)機(ji)(ji)故(gu)障發(fa)(fa)生幾率。首先，保(bao)證接(jie)地(di)裝(zhuang)置效果(guo)(guo)良好是(shi)防(fang)(fang)雷(lei)(lei)措施的(de)(de)前提，因為(wei)所有(you)(you)(you)感(gan)應電(dian)(dian)(dian)流最后都是(shi)要(yao)(yao)泄(xie)入(ru)(ru)(ru)(ru)大(da)地(di)的(de)(de)。一(yi)般而(er)言(yan)，接(jie)地(di)電(dian)(dian)(dian)阻越小(xiao)泄(xie)流效果(guo)(guo)越好，通(tong)常(chang)將接(jie)地(di)電(dian)(dian)(dian)阻控(kong)制在4歐姆(mu)以(yi)內為(wei)佳，可使(shi)用接(jie)地(di)鉗表對接(jie)地(di)電(dian)(dian)(dian)阻進行測量。對于某些土(tu)壤(rang)電(dian)(dian)(dian)阻率高的(de)(de)地(di)方(fang)，可以(yi)考(kao)慮在土(tu)壤(rang)中加入(ru)(ru)(ru)(ru)降(jiang)阻劑，從而(er)降(jiang)低(di)接(jie)地(di)電(dian)(dian)(dian)阻。其次(ci)，前端(duan)(duan)設備要(yao)(yao)加裝(zhuang)浪(lang)(lang)涌(yong)(yong)(yong)保(bao)護(hu)器(qi)(qi)(qi)，正常(chang)電(dian)(dian)(dian)壓(ya)(ya)時，浪(lang)(lang)涌(yong)(yong)(yong)保(bao)護(hu)器(qi)(qi)(qi)呈(cheng)(cheng)高阻狀(zhuang)態(tai)，只有(you)(you)(you)很(hen)(hen)小(xiao)的(de)(de)泄(xie)漏電(dian)(dian)(dian)流，功率損耗很(hen)(hen)小(xiao)，當線路中出(chu)現過(guo)(guo)壓(ya)(ya)時，浪(lang)(lang)涌(yong)(yong)(yong)保(bao)護(hu)器(qi)(qi)(qi)呈(cheng)(cheng)低(di)阻狀(zhuang)態(tai)，過(guo)(guo)電(dian)(dian)(dian)壓(ya)(ya)以(yi)放電(dian)(dian)(dian)電(dian)(dian)(dian)流的(de)(de)形(xing)式通(tong)過(guo)(guo)浪(lang)(lang)涌(yong)(yong)(yong)保(bao)護(hu)器(qi)(qi)(qi)流入(ru)(ru)(ru)(ru)大(da)地(di)，過(guo)(guo)電(dian)(dian)(dian)壓(ya)(ya)被抑制下來，浪(lang)(lang)涌(yong)(yong)(yong)電(dian)(dian)(dian)壓(ya)(ya)過(guo)(guo)后，線路電(dian)(dian)(dian)壓(ya)(ya)恢復正常(chang)時，浪(lang)(lang)涌(yong)(yong)(yong)保(bao)護(hu)器(qi)(qi)(qi)又呈(cheng)(cheng)高阻絕緣狀(zhuang)態(tai)，因此浪(lang)(lang)涌(yong)(yong)(yong)保(bao)護(hu)器(qi)(qi)(qi)必(bi)(bi)須有(you)(you)(you)良好的(de)(de)接(jie)地(di)裝(zhuang)置與之(zhi)配合。前端(duan)(duan)攝像機(ji)(ji)的(de)(de)視頻(pin)信號輸出(chu)口(kou)(kou)和發(fa)(fa)射機(ji)(ji)的(de)(de)視頻(pin)輸入(ru)(ru)(ru)(ru)口(kou)(kou)處(chu)接(jie)浪(lang)(lang)涌(yong)(yong)(yong)保(bao)護(hu)器(qi)(qi)(qi)，若發(fa)(fa)射機(ji)(ji)連(lian)有(you)(you)(you)其他一(yi)些數(shu)據線時，需要(yao)(yao)在控(kong)制信號線的(de)(de)起始端(duan)(duan)和結束(shu)端(duan)(duan)加裝(zhuang)數(shu)據防(fang)(fang)雷(lei)(lei)器(qi)(qi)(qi)，并在攝像機(ji)(ji)和光端(duan)(duan)機(ji)(ji)的(de)(de)電(dian)(dian)(dian)源輸入(ru)(ru)(ru)(ru)端(duan)(duan)也加上電(dian)(dian)(dian)源防(fang)(fang)雷(lei)(lei)器(qi)(qi)(qi)等防(fang)(fang)雷(lei)(lei)設備。裝(zhuang)防(fang)(fang)雷(lei)(lei)器(qi)(qi)(qi)時務必(bi)(bi)使(shi)防(fang)(fang)雷(lei)(lei)器(qi)(qi)(qi)緊貼接(jie)入(ru)(ru)(ru)(ru)口(kou)(kou)，若防(fang)(fang)雷(lei)(lei)器(qi)(qi)(qi)距(ju)離視頻(pin)口(kou)(kou)、數(shu)據口(kou)(kou)太遠是(shi)發(fa)(fa)揮(hui)不了防(fang)(fang)雷(lei)(lei)效果(guo)(guo)的(de)(de)。

加好(hao)防雷設備(bei)后，剩下的(de)(de)便(bian)是接(jie)地(di)網的(de)(de)設計問題。接(jie)地(di)樁一(yi)定要打到(dao)位，保證(zheng)光端機良好(hao)接(jie)地(di)，一(yi)個(ge)(ge)好(hao)的(de)(de)低阻(zu)抗接(jie)地(di)網設計能(neng)夠保證(zheng)系統中的(de)(de)防雷設備(bei)發揮良好(hao)效(xiao)(xiao)果且(qie)能(neng)有效(xiao)(xiao)均衡整(zheng)個(ge)(ge)傳輸系統內各(ge)部(bu)位電(dian)壓，防止地(di)電(dian)位差對(dui)線路中設備(bei)的(de)(de)干(gan)擾(rao)，同(tong)時也可有效(xiao)(xiao)避免地(di)電(dian)位反擊對(dui)設備(bei)的(de)(de)損壞。