Mazuva ano, PLC inogona kugamuchira encoder uye sensor masiginecha isina amplifier, saka chii chinonakidza che "source" uye "drain"? Chete chinobuda chePLC chichava nemafungiro e "source" uye "leakage".

Muchokwadi, kunze kweJapan PLC, hazvifanirwe kuti mamwe maPLC ashandise zvipfupiso senge "source" uye "drain", asi PNP neNPN zvinogona kushandiswa zvakananga.

PNP ndeye yakaderera-voltage yeruzhinji mutsetse, uye NPN ndeye yakakwira-voltage yeruzhinji mutsetse. Chero bedzi kubatana uku kuri kwechokwadi, zvinoita sekunge hazvina basa kana pfungwa dze "source" uye "drain" dzakadzoserwa kumashure. Nekudaro, imwe pfungwa "positive logic uye negative logic" hainawo, izvo zvinozoita kuti chiratidzo chidzoserwe.

Positive logic uye negative logic

MuPNP-mhando maseketi, iyo yakajairika terminal yemagetsi uye siginecha iri padanho rakaderera re0V. Kana iyo yekuisa iri padanho rakaderera, hapana mutsauko wevoltage neyakajairwa terminal, saka hapana amplified switching signal inobuda (digital quantity is 0). Chete kana iyo yekuisa iri padanho repamusoro, pane musiyano wevoltage neyakajairwa terminal uye inosimudzira switching chiratidzo inobuda padanho repamusoro. Iyi digital mode (digital quantity is 1) iyo inoshanda kana chiratidzo chiri pakakwirira chinonzi PNP positive logic.

Muchikamu cheNPN, iyo yakajairika terminal yemagetsi uye chiratidzo chiri padanho repamusoro (hunhu hweiyi amplifier circuit). Kana iyo yekuisa iri padanho repamusoro, hapana mutsauko wevoltage pakati pekupinza uye yakabuda, saka hapana chekuchinja chiratidzo chinobuda (iyo yedhijitari huwandu 0). Chete kana iyo yekupinza iri padanho rakaderera (kuumba funnel), pane inochinja chiratidzo chinobuda, uye chiratidzo ichi chinoshanda (digital uwandu ndeye 1) digital mode pane yakaderera, iyo inonzi NPN negative logic.