請(qǐng)教各位:在三菱PLC控制伺服電機(jī)時(shí),有時(shí)需要原點(diǎn)回歸,但在原點(diǎn)回歸指令ZRN時(shí)卻沒(méi)有指定運(yùn)行方向,但是當(dāng)伺服處于原點(diǎn)的負(fù)方向時(shí),它應(yīng)該正轉(zhuǎn)回歸原點(diǎn);當(dāng)伺服處于原點(diǎn)的正方向時(shí),它應(yīng)該反轉(zhuǎn)回歸原點(diǎn).是否在運(yùn)行過(guò)程中伺服電機(jī)能判斷在啟動(dòng)時(shí)的初始位置在原點(diǎn)的正反方向?

請(qǐng)問(wèn)版主如果是控制步進(jìn)電機(jī) ，只用一個(gè)光電開關(guān)回原點(diǎn)怎么做
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