一、交流接觸器常開與常閉觸點的作用
常(chang)規(gui)L1,L2,L3為(wei)A相,B相,C相電(dian)源(yuan)進線(xian)。
A1,A2為接觸器線圈兩端。有兩個A2是廠家(jia)為方便接(jie)(jie)(jie)線,A2有兩個接(jie)(jie)(jie)線點,是一(yi)樣的,接(jie)(jie)(jie)線時可以A1,A2接(jie)(jie)(jie)在接(jie)(jie)(jie)觸(chu)(chu)器一(yi)側,也可以接(jie)(jie)(jie)在接(jie)(jie)(jie)觸(chu)(chu)器兩側。
13NO,14NO為(wei)常(chang)閉接(jie)點。
NC和(he)(he)NO都是(shi)輔助觸點(dian)(dian)(dian)(dian)(dian),NC是(shi)常(chang)(chang)閉點(dian)(dian)(dian)(dian)(dian),NO是(shi)常(chang)(chang)開(kai)點(dian)(dian)(dian)(dian)(dian)。NO和(he)(he)NC的(de)觸點(dian)(dian)(dian)(dian)(dian)編(bian)號是(shi)有規(gui)律的(de)。11和(he)(he)12是(shi)一對常(chang)(chang)閉點(dian)(dian)(dian)(dian)(dian),13和(he)(he)14是(shi)一對常(chang)(chang)開(kai)點(dian)(dian)(dian)(dian)(dian),21和(he)(he)22是(shi)一對常(chang)(chang)閉點(dian)(dian)(dian)(dian)(dian),23和(he)(he)24是(shi)一對常(chang)(chang)開(kai)點(dian)(dian)(dian)(dian)(dian),以此類推,凡是(shi)有2的(de)點(dian)(dian)(dian)(dian)(dian),都是(shi)常(chang)(chang)閉點(dian)(dian)(dian)(dian)(dian),有4的(de)點(dian)(dian)(dian)(dian)(dian),都是(shi)常(chang)(chang)開(kai)點(dian)(dian)(dian)(dian)(dian)。偶數(shu)編(bian)號是(shi)引出端(duan),奇數(shu)編(bian)號是(shi)公共端(duan)。
常(chang)開 ——在接觸(chu)器(qi)沒(mei)工作的情況(kuang)下,該觸(chu)點為開路。
常閉 ——在接觸器工(gong)作的(de)情(qing)況下,該觸點為閉合。
工作時,常(chang)閉(bi)觸點(dian)先斷開(kai),常(chang)開(kai)觸點(dian)再閉(bi)合(he)。當(dang)接觸器線圈斷電(dian)時,常(chang)開(kai)觸點(dian)先斷開(kai),常(chang)閉(bi)觸點(dian)才閉(bi)合(he)復位。
常閉點(dian)(dian)跟常開點(dian)(dian)相當于(yu)兩(liang)個開關,只是起到接(jie)(jie)通和關斷(duan)線路的(de)(de)(de)作用(yong)。你在常開點(dian)(dian)外接(jie)(jie)的(de)(de)(de)是多(duo)大(da)的(de)(de)(de)電壓,當線圈吸合時(shi),常開點(dian)(dian)上(shang)的(de)(de)(de)電壓就是多(duo)大(da)。
二、交流接觸器常開常閉怎么區分
交流(liu)接(jie)觸器中的常開(kai)輔助接(jie)頭是指在接(jie)觸器不通電(dian)的狀(zhuang)態下(xia),總處于(yu)(yu)打開(kai)的狀(zhuang)態,長(chang)(chang)閉(bi)觸點(dian)也是指接(jie)觸器在不通電(dian)狀(zhuang)態下(xia),總是處于(yu)(yu)閉(bi)合的狀(zhuang)態。若通電(dian)接(jie)觸器處于(yu)(yu)工作狀(zhuang)態,則長(chang)(chang)開(kai)閉(bi)合,長(chang)(chang)閉(bi)打開(kai)。
一般長開觸(chu)(chu)點(dian)應用(yong)于電機(ji)的(de)一般控制(zhi)(zhi),一端接線(xian)(xian)(xian)(xian)圈和控制(zhi)(zhi)線(xian)(xian)(xian)(xian),另(ling)端接連鎖線(xian)(xian)(xian)(xian)。長閉觸(chu)(chu)點(dian)和長開配合用(yong)于控制(zhi)(zhi)電機(ji)正反轉(需要(yao)兩個同樣的(de)接觸(chu)(chu)器(qi)(qi))正轉時用(yong)反轉的(de)接觸(chu)(chu)器(qi)(qi)鎖線(xian)(xian)(xian)(xian)圈,反轉時則相反。也可以用(yong)來(lai)控制(zhi)(zhi)四線(xian)(xian)(xian)(xian)三(san)相配電的(de)零線(xian)(xian)(xian)(xian)。用(yong)得最常見就是常開自鎖,常閉互鎖了,分辨標著N。
其實分清楚哪里是常開的端子和哪里是常閉的端子很簡單,一是看接觸器上(shang)(shang)面的(de)標簽,如上(shang)(shang)圖所示,都會(hui)標明多少(shao)號端子和多少(shao)號端子是(shi)(shi)一對(dui)常閉的(de)或是(shi)(shi)常開的(de)。如果是(shi)(shi)老舊的(de)接觸(chu)(chu)器,已經(jing)看不(bu)清標識也沒關(guan)系,你可以(yi)拆掉(diao)接觸(chu)(chu)器上(shang)(shang)面的(de)蓋子,這樣就可以(yi)看到哪一對(dui)是(shi)(shi)常開的(de),哪一對(dui)是(shi)(shi)常閉的(de)了,要(yao)不(bu)然用萬用表量也可以(yi)的(de)。