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        避雷器特性

        2014/1/14 8:37:16      點(diǎn)擊:
        避雷器 七大特性:
        一、氧化鋅避雷器的通流能力大
        這主要體現(xiàn)在避雷器具有吸收各種雷電過電壓、工頻暫態(tài)過電壓、操作過電壓的能力。川泰生產(chǎn)的氧化鋅避雷器的通流能力完全符合甚至高于國家標(biāo)準(zhǔn)的要求。線路放電等級(jí)、能量吸收能力、4/10納秒大電流沖擊耐受、2ms方波通流能力等指標(biāo)達(dá)到了國內(nèi)領(lǐng)先水平。
        二、氧化鋅避雷器的保護(hù)特性優(yōu)異
        氧化鋅避雷器是用來保護(hù)電力系統(tǒng)中各種電器設(shè)備免受過電壓損壞的電器產(chǎn)品,具有良好保護(hù)性能。因?yàn)檠趸\閥片的非線性伏安特性十分優(yōu)良,使得在正常工作電壓下僅有幾百微安的電流通過,便于設(shè)計(jì)成無間隙結(jié)構(gòu),使其具備保護(hù)性能好、重量輕、尺寸小的特征。當(dāng)過電壓侵入時(shí),流過閥片的電流迅速增大,同時(shí)限制了過電壓的幅值,釋放了過電壓的能量,此后氧化鋅閥片又恢復(fù)高阻狀態(tài),使電力系統(tǒng)正常工作。
        三、氧化鋅避雷器的密封性能良好
        避雷器元件采用老化性能好、氣密性好的優(yōu)質(zhì)復(fù)合外套,采用控制密封圈壓縮量和增涂密封膠等措施,陶瓷外套作為密封材料,確保密封可靠,使避雷器的性能穩(wěn)定。
        四、氧化鋅避雷器的機(jī)械性能
        主要考慮以下三方面因素:
        ⑴承受的地震力;
        ⑵作用于避雷器上的最大風(fēng)壓力
        ⑶避雷器的頂端承受導(dǎo)線的最大允許拉力。
        五、氧化鋅避雷器的良好的解污穢性能
        無間隙氧化鋅避雷器具有較高的耐污穢性能。
        目前國家標(biāo)準(zhǔn)規(guī)定的爬電比距等級(jí)為:
        ⑴II級(jí) 中等污穢地區(qū):爬電比距20mm/kv
        ⑵III級(jí) 重污穢地區(qū):爬電比距25mm/kv
        ⑶IV級(jí) 特重污穢地區(qū):爬電比距31mm/kv
        六、氧化鋅避雷器的高運(yùn)行可靠性
        長(zhǎng)期運(yùn)行的可靠性取決于產(chǎn)品的質(zhì)量,及對(duì)產(chǎn)品的選型是否合理。影響它的產(chǎn)品質(zhì)量主要有以下三方面:
        A 避雷器整體結(jié)構(gòu)的合理性;
        B 氧化鋅閥片的伏安特性及耐老化特性
        C 避雷器的密封性能。
        七、工頻耐受能力
        由于電力系統(tǒng)中如單相接地、長(zhǎng)線電容效應(yīng)以及甩負(fù)荷等各種原因,會(huì)引起工頻電壓的升高或產(chǎn)生幅值較高的暫態(tài)過電壓,避雷器具有在一定時(shí)間內(nèi)承受一定工頻電壓升高能力。
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