【繼(ji)電器(qi)工作原理】繼(ji)電器(qi)工作原理分析(xi) 熱過載繼(ji)電器(qi)的結構特征
繼電器是什么
當它接入(ru)主電(dian)(dian)(dian)(dian)路內,流過與電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)機(ji)相同電(dian)(dian)(dian)(dian)流,當電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)機(ji)過載(zai)時,熱(re)(re)元件被(bei)加熱(re)(re)到動(dong)(dong)(dong)作(zuo)溫度(du),使熱(re)(re)繼(ji)電(dian)(dian)(dian)(dian)器(qi)動(dong)(dong)(dong)作(zuo)。熱(re)(re)繼(ji)電(dian)(dian)(dian)(dian)器(qi)的(de)動(dong)(dong)(dong)作(zuo)時間與過載(zai)電(dian)(dian)(dian)(dian)流的(de)大小(xiao)按反時限關系變(bian)化〔而作(zuo)為電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)機(ji)過載(zai)保護的(de)熱(re)(re)繼(ji)電(dian)(dian)(dian)(dian)器(qi),必須保證電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)機(ji)的(de)正(zheng)常起動(dong)(dong)(dong)和運行不受影響,并能(neng)(neng)最(zui)大限度(du)的(de)發(fa)揮電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)機(ji)的(de)承(cheng)載(zai)能(neng)(neng)力(li),因此熱(re)(re)繼(ji)電(dian)(dian)(dian)(dian)器(qi)的(de)動(dong)(dong)(dong)作(zuo)特性曲(qu)線應位于(yu)電(dian)(dian)(dian)(dian)動(dong)(dong)(dong)機(ji)的(de)允許發(fa)熱(re)(re)特性曲(qu)線的(de)下方(fang),且(qie)又接近于(yu)它。
繼電器的工作原理分析
1、電磁繼電器的工作原理和特性
電磁式繼電器一般由鐵芯、線圈、銜鐵、觸點簧片等組成的。只要在線圈兩端加上一定的電壓,線圈中就會流過一定的電流,從而產生電磁效應,銜鐵就會在電磁力吸引的作用下克服返回彈簧的拉力吸向鐵芯,從而帶動銜鐵的動觸點與靜觸點(常(chang)開觸點)吸(xi)合。當線圈斷電后(hou),電磁的(de)吸(xi)力(li)也隨(sui)之(zhi)消失,銜鐵就(jiu)會在彈簧的(de)反作用力(li)返回原(yuan)來(lai)的(de)位置(zhi),使動觸點與原(yuan)來(lai)的(de)靜觸點(常閉觸(chu)點)吸合。這(zhe)樣吸合、釋(shi)放(fang),從而達(da)到了在(zai)電路中(zhong)的(de)導通、切斷的(de)目的(de)。對(dui)于(yu)(yu)繼電器的(de)“常(chang)(chang)開(kai)、常(chang)(chang)閉”觸(chu)(chu)點,可(ke)以這(zhe)樣來區分:繼電器線圈(quan)未通電時處于(yu)(yu)斷開(kai)狀態的(de)靜觸(chu)(chu)點,稱為“常(chang)(chang)開(kai)觸(chu)(chu)點”;處于(yu)(yu)接通狀態的(de)靜觸(chu)(chu)點稱為“常(chang)(chang)閉觸(chu)(chu)點”。
2、熱敏干簧繼電器的工作原理和特性
熱(re)(re)敏(min)干簧(huang)(huang)繼電器是一種利用熱(re)(re)敏(min)磁(ci)(ci)性材料檢測和控(kong)制溫(wen)度(du)的(de)新(xin)型熱(re)(re)敏(min)開(kai)(kai)關。它由(you)(you)感溫(wen)磁(ci)(ci)環(huan)(huan)(huan)、恒(heng)磁(ci)(ci)環(huan)(huan)(huan)、干簧(huang)(huang)管、導熱(re)(re)安裝(zhuang)片、塑料襯底及(ji)其(qi)他一些附(fu)件組成。熱(re)(re)敏(min)干簧(huang)(huang)繼電器不(bu)用線圈(quan)勵(li)磁(ci)(ci),而由(you)(you)恒(heng)磁(ci)(ci)環(huan)(huan)(huan)產(chan)生(sheng)的(de)磁(ci)(ci)力驅動開(kai)(kai)關動作。恒(heng)磁(ci)(ci)環(huan)(huan)(huan)能否向干簧(huang)(huang)管提供磁(ci)(ci)力是由(you)(you)感溫(wen)磁(ci)(ci)環(huan)(huan)(huan)的(de)溫(wen)控(kong)特(te)性決定的(de)。
3、固態繼電器(SSR)的工作原理和特性
固態繼(ji)電(dian)器(qi)(qi)是(shi)一(yi)種兩個接線(xian)端為輸入端,另兩個接線(xian)端為輸出(chu)端的四端器(qi)(qi)件,中間采用隔(ge)離器(qi)(qi)件實現輸入輸出(chu)的電(dian)隔(ge)離。
固態繼(ji)電(dian)器按負載電(dian)源類型(xing)(xing)(xing)(xing)(xing)可(ke)分(fen)為(wei)(wei)(wei)交流(liu)型(xing)(xing)(xing)(xing)(xing)和(he)直(zhi)流(liu)型(xing)(xing)(xing)(xing)(xing)。按開關型(xing)(xing)(xing)(xing)(xing)式可(ke)分(fen)為(wei)(wei)(wei)常開型(xing)(xing)(xing)(xing)(xing)和(he)常閉型(xing)(xing)(xing)(xing)(xing)。按隔(ge)離(li)(li)型(xing)(xing)(xing)(xing)(xing)式可(ke)分(fen)為(wei)(wei)(wei)混合型(xing)(xing)(xing)(xing)(xing)、變壓器隔(ge)離(li)(li)型(xing)(xing)(xing)(xing)(xing)和(he)光電(dian)隔(ge)離(li)(li)型(xing)(xing)(xing)(xing)(xing),以光電(dian)隔(ge)離(li)(li)型(xing)(xing)(xing)(xing)(xing)為(wei)(wei)(wei)最多(duo)。
繼電器主要產品技術參數
1、額(e)定(ding)工作電壓
是指(zhi)繼(ji)電(dian)(dian)器正(zheng)常工作(zuo)時線(xian)圈所需要的電(dian)(dian)壓。根(gen)據繼(ji)電(dian)(dian)器的型(xing)號不(bu)同,可以是交流電(dian)(dian)壓,也可以是直流電(dian)(dian)壓。
2、直(zhi)流電阻
是指繼電器(qi)中(zhong)線圈的直(zhi)流電阻,可以通過(guo)萬能表測量(liang)。
3、吸合電(dian)流
是指繼電器能夠產生吸合動作的最小電流。在正常使用時,給定的電流必須略大于吸合電流,這樣繼電器才能穩定地工作。而對于線圈所加的工作電壓,一般不要超過額定工作電壓的1.5倍(bei),否則會(hui)產生較大的(de)電流而把線圈燒毀。
4、釋放電流
是指(zhi)繼電(dian)(dian)(dian)器產生釋(shi)放(fang)動(dong)作的最(zui)大電(dian)(dian)(dian)流(liu)。當(dang)繼電(dian)(dian)(dian)器吸合狀態的電(dian)(dian)(dian)流(liu)減(jian)小到一定程(cheng)度時(shi),繼電(dian)(dian)(dian)器就會(hui)恢復(fu)到未通電(dian)(dian)(dian)的釋(shi)放(fang)狀態。這時(shi)的電(dian)(dian)(dian)流(liu)遠遠小于吸合電(dian)(dian)(dian)流(liu)。
5、觸點切換電(dian)壓和(he)電(dian)流
是指繼電(dian)(dian)器(qi)允許(xu)加載(zai)的電(dian)(dian)壓(ya)和(he)電(dian)(dian)流。它決定了繼電(dian)(dian)器(qi)能控(kong)制電(dian)(dian)壓(ya)和(he)電(dian)(dian)流的大(da)小(xiao),使(shi)用時不能超過此值,否則很容易損壞(huai)繼電(dian)(dian)器(qi)的觸點。
熱過載繼電器的結構特征
有電流調節凸輪用以(yi)調節整(zheng)定(ding)電流。
有溫(wen)度補償裝置以保(bao)證(zheng)動作特性在(zai)-20C~60C的周圍(wei)介質(zhi)溫(wen)度范圍(wei)內基本不變。
有(you)復位(wei)(wei)調節旋鈕用(yong)以調節復位(wei)(wei)方式,有(you)手動(dong)和(he)自動(dong)二種復位(wei)(wei)狀態。
有拉伸彈簧翻(fan)轉跳(tiao)躍機構以保(bao)證觸(chu)頭動作迅速可靠(kao)。
有(you)差動(dong)式斷相/三相不平衡(heng)保(bao)護裝置。
有檢(jian)測滑(hua)塊/開關位置指(zhi)示器模擬(ni)熱(re)繼電器的脫扣并顯(xian)示動作狀態(tai)。通過這種(zhong)模擬(ni)方(fang)式檢(jian)查(cha)并確保輔助電路(lu)接線正確。當滑(hua)塊上的標(biao)(biao)線位于(yu)“0”標(biao)(biao)志處顯(xian)示脫扣,位于(yu)“l”標(biao)(biao)志處顯(xian)示工(gong)作。
有斷(duan)開(kai)按鈕(niu),按下(xia)斷(duan)開(kai)按鈕(niu)時,常閉觸頭打開(kai)串聯接觸器開(kai)路(lu),斷(duan)開(kai)負載(zai),釋放(fang)斷(duan)開(kai)按鈕(niu)后(hou),負載(zai)通過接觸器重新工作。