一、光電開關是模擬量還是數字量
光電開關的(de)信號通(tong)常為數(shu)字量。
由(you)于光(guang)(guang)電開(kai)關(guan)的輸(shu)(shu)出信號往往只有兩種情況(kuang),即有光(guang)(guang)和(he)斷光(guang)(guang)。因(yin)(yin)(yin)此,受到(dao)檢(jian)測物(wu)體大小、光(guang)(guang)源亮度、反(fan)射度等因(yin)(yin)(yin)素的影響,無法保證模擬(ni)量(liang)的穩定性(xing)和(he)準(zhun)確(que)性(xing)。相比之下,數(shu)字量(liang)信號不受這(zhe)些因(yin)(yin)(yin)素的影響,根據輸(shu)(shu)出的電壓或電流值是(shi)否超過設定門檻(jian),輸(shu)(shu)出0或1的數(shu)字信號更(geng)加穩定、準(zhun)確(que),且易于處理和(he)傳輸(shu)(shu),因(yin)(yin)(yin)此光(guang)(guang)電開(kai)關(guan)通常輸(shu)(shu)出數(shu)字量(liang)信號。
二、光電開關是直流還是交流
光電開關的供電可(ke)(ke)以是直(zhi)流(liu)也可(ke)(ke)以是交(jiao)流(liu)。
光(guang)(guang)電(dian)(dian)(dian)開(kai)(kai)關(guan)(guan)的(de)(de)供(gong)電(dian)(dian)(dian)種類包括直(zhi)流(liu)(liu)(liu)(liu)(liu)式(shi)、交(jiao)(jiao)流(liu)(liu)(liu)(liu)(liu)式(shi)和直(zhi)流(liu)(liu)(liu)(liu)(liu)交(jiao)(jiao)流(liu)(liu)(liu)(liu)(liu)混(hun)合式(shi)三種。直(zhi)流(liu)(liu)(liu)(liu)(liu)式(shi)光(guang)(guang)電(dian)(dian)(dian)開(kai)(kai)關(guan)(guan)采用(yong)直(zhi)流(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)壓(ya)供(gong)電(dian)(dian)(dian),電(dian)(dian)(dian)壓(ya)范圍(wei)一般為(wei)12-24V(10-30V)的(de)(de)直(zhi)流(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)壓(ya)。交(jiao)(jiao)流(liu)(liu)(liu)(liu)(liu)式(shi)光(guang)(guang)電(dian)(dian)(dian)開(kai)(kai)關(guan)(guan)則(ze)采用(yong)交(jiao)(jiao)流(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)壓(ya)供(gong)電(dian)(dian)(dian),電(dian)(dian)(dian)壓(ya)范圍(wei)為(wei)90-240V交(jiao)(jiao)流(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian),適(shi)用(yong)于(yu)110VAC與220VAC場合的(de)(de)供(gong)電(dian)(dian)(dian)。而(er)直(zhi)流(liu)(liu)(liu)(liu)(liu)交(jiao)(jiao)流(liu)(liu)(liu)(liu)(liu)混(hun)合式(shi)光(guang)(guang)電(dian)(dian)(dian)開(kai)(kai)關(guan)(guan)則(ze)允許直(zhi)流(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)壓(ya)與交(jiao)(jiao)流(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)壓(ya)都(dou)可(ke)以(yi)直(zhi)接接入同一個供(gong)電(dian)(dian)(dian)回路,直(zhi)流(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)壓(ya)范圍(wei)為(wei)12-240V,交(jiao)(jiao)流(liu)(liu)(liu)(liu)(liu)電(dian)(dian)(dian)壓(ya)范圍(wei)為(wei)24-240V,這種形式(shi)具(ju)有(you)較高的(de)(de)適(shi)應性,不需要考慮配(pei)電(dian)(dian)(dian)的(de)(de)問題。
因(yin)此(ci),光(guang)電(dian)(dian)(dian)開關的(de)供電(dian)(dian)(dian)方(fang)式既可(ke)以是直流也可(ke)以是交流,具體取決于其設計時所(suo)采用的(de)供電(dian)(dian)(dian)形式。
三、光電開關是有源還是無源
光電開關既有有源型,也有無(wu)源型。
1、有源型光電開關:需要另外提供(gong)一(yi)個電源或信號源才(cai)能驅動它(ta)的工作。例(li)如,光電耦合器、光電轉換器等。
2、無源型光電開關:不需(xu)要外部電(dian)源或信號(hao)(hao)(hao)源,它可以(yi)直接(jie)將光信號(hao)(hao)(hao)轉換成電(dian)信號(hao)(hao)(hao)輸出。例如(ru),光電(dian)二(er)極管、光敏三極管等。
需(xu)要注意的是(shi),無源型(xing)(xing)光(guang)電開關需(xu)要有較高的光(guang)照強度才能(neng)工作,因此其檢測(ce)距離一般(ban)比有源型(xing)(xing)的短。