一、光電開關是模擬量還是數字量
光(guang)電開(kai)關的信號通常(chang)為(wei)數字(zi)量。
由于光(guang)(guang)(guang)電(dian)開關的(de)輸(shu)(shu)出信(xin)號(hao)往(wang)往(wang)只有(you)兩種情況,即有(you)光(guang)(guang)(guang)和斷光(guang)(guang)(guang)。因(yin)此,受(shou)到檢測物體大小、光(guang)(guang)(guang)源(yuan)亮度、反射度等(deng)因(yin)素的(de)影(ying)響,無法保證模擬量的(de)穩定(ding)性和準確性。相比之下,數字(zi)(zi)量信(xin)號(hao)不受(shou)這些(xie)因(yin)素的(de)影(ying)響,根據輸(shu)(shu)出的(de)電(dian)壓或電(dian)流值是否(fou)超(chao)過設定(ding)門檻,輸(shu)(shu)出0或1的(de)數字(zi)(zi)信(xin)號(hao)更加穩定(ding)、準確,且易于處理和傳輸(shu)(shu),因(yin)此光(guang)(guang)(guang)電(dian)開關通常輸(shu)(shu)出數字(zi)(zi)量信(xin)號(hao)。
二、光電開關是直流還是交流
光(guang)電開關的供電可(ke)以是直流也可(ke)以是交流。
光電(dian)(dian)(dian)開關的(de)供(gong)電(dian)(dian)(dian)種類包括直流(liu)(liu)式(shi)(shi)(shi)、交流(liu)(liu)式(shi)(shi)(shi)和直流(liu)(liu)交流(liu)(liu)混合式(shi)(shi)(shi)三種。直流(liu)(liu)式(shi)(shi)(shi)光電(dian)(dian)(dian)開關采用(yong)直流(liu)(liu)電(dian)(dian)(dian)壓(ya)(ya)供(gong)電(dian)(dian)(dian),電(dian)(dian)(dian)壓(ya)(ya)范圍(wei)(wei)一般為(wei)(wei)(wei)12-24V(10-30V)的(de)直流(liu)(liu)電(dian)(dian)(dian)壓(ya)(ya)。交流(liu)(liu)式(shi)(shi)(shi)光電(dian)(dian)(dian)開關則采用(yong)交流(liu)(liu)電(dian)(dian)(dian)壓(ya)(ya)供(gong)電(dian)(dian)(dian),電(dian)(dian)(dian)壓(ya)(ya)范圍(wei)(wei)為(wei)(wei)(wei)90-240V交流(liu)(liu)電(dian)(dian)(dian),適(shi)用(yong)于(yu)110VAC與220VAC場合的(de)供(gong)電(dian)(dian)(dian)。而直流(liu)(liu)交流(liu)(liu)混合式(shi)(shi)(shi)光電(dian)(dian)(dian)開關則允許直流(liu)(liu)電(dian)(dian)(dian)壓(ya)(ya)與交流(liu)(liu)電(dian)(dian)(dian)壓(ya)(ya)都可以直接(jie)接(jie)入(ru)同一個供(gong)電(dian)(dian)(dian)回路,直流(liu)(liu)電(dian)(dian)(dian)壓(ya)(ya)范圍(wei)(wei)為(wei)(wei)(wei)12-240V,交流(liu)(liu)電(dian)(dian)(dian)壓(ya)(ya)范圍(wei)(wei)為(wei)(wei)(wei)24-240V,這種形式(shi)(shi)(shi)具有較高的(de)適(shi)應性,不需要(yao)考慮(lv)配電(dian)(dian)(dian)的(de)問題。
因此,光(guang)電開關(guan)的(de)供電方式既(ji)可以是(shi)直流(liu)也可以是(shi)交流(liu),具體取決于其設計時所采用的(de)供電形式。
三、光電開關是有源還是無源
光電(dian)開關既(ji)有(you)有(you)源型,也有(you)無(wu)源型。
1、有源型光電開關:需要(yao)另(ling)外提供一個電源(yuan)或信號源(yuan)才能驅動它的(de)工作(zuo)。例如,光電耦合(he)器(qi)、光電轉換器(qi)等。
2、無源型光電開關:不需要外部(bu)電源(yuan)或(huo)信(xin)號源(yuan),它可以直接將光信(xin)號轉換成電信(xin)號輸(shu)出。例如,光電二極管、光敏三極管等。
需(xu)要注意的是,無源型(xing)光(guang)電(dian)開關需(xu)要有較高的光(guang)照強度才(cai)能工作,因(yin)此其檢測距離一般比(bi)有源型(xing)的短。