PME光電自動數粒儀是專門用於對各種糧食作物種子進行數粒的，種子粒子有大小之分，相應的也有專門針對大小粒子的種子數粒儀。如PME型種子數粒儀適用於大小粒種子，PME-1型種子數粒儀僅適用於小粒種子。

PME光電自動數粒儀包括電磁振動送料裝置、自動數粒儀計數顯示電路和自停電路的控製信號。PME光(guang)電(dian)自(zi)動(dong)數(shu)粒(li)儀(yi)的(de)電(dian)磁(ci)振(zhen)動(dong)送(song)料(liao)裝(zhuang)置(zhi)是(shi)當(dang)種(zhong)子(zi)放(fang)在(zai)料(liao)盤(pan)時(shi)
，料(liao)槽(cao)成(cheng)螺(luo)旋(xuan)形(xing)。種(zhong)子(zi)隨(sui)著(zhe)螺(luo)旋(xuan)槽(cao)上(shang)升(sheng)，當(dang)到(dao)達(da)落(luo)料(liao)口(kou)時(shi)，落(luo)下(xia)，通(tong)過(guo)光(guang)電(dian)轉(zhuan)換(huan)區(qu)投(tou)影(ying)到(dao)矽(gui)光(guang)電(dian)池(chi)上(shang)產(chan)生(sheng)電(dian)流(liu)變(bian)化(hua)，經(jing)脈(mai)動(dong)放(fang)大(da)整(zheng)形(xing)後(hou)得(de)到(dao)光(guang)電(dian)計(ji)數(shu)脈(mai)動(dong)，送(song)入(ru)計(ji)數(shu)電(dian)路(lu)計(ji)數(shu)顯(xian)示(shi)。光(guang)電(dian)自(zi)動(dong)數(shu)粒(li)儀(yi)計(ji)數(shu)顯(xian)示(shi)電(dian)路(lu)采(cai)用(yong)4為LED顯示，也就說明最大計數值為9999粒種子。而預置自停電路的控製信號
，則由開關二極管、指zhi輪lun拔ba盤pan開kai關guan與yu四si輸shu入ru端duan的de與yu非fei門men聯lian接jie，當dang三san個ge中zhong任ren意yi一yi個ge設she置zhi為wei非fei時shi，才cai會hui切qie斷duan電dian源yuan。即ji此ci時shi撥bo盤pan預yu置zhi數shu與yu計ji數shu器qi上shang顯xian示shi的de數shu字zi一yi致zhi時shi，計ji數shu輸shu入ru被bei切qie斷duan，計ji數shu停ting止zhi。

光電數粒儀changchangyongzaigezhongzhongzideqianlizhongcanshucedingshang，zaidangqianzhongzijianyanzhongguangweishiyong
，keyishuoshiyikuanbukequeshaodeyiqi。danshisuizhekexuejishudejinbu
，gengweifangbiankuaijie，tongshijingquedugenggaodeyiqiyeyingyunershengle
，najiushiweidiannaozidongshuliyi，tarongruleweidiannaokongzhiyuansu
，zhenzhengshixianlequanzidongkongzhi。