I kēia mau lā, hiki i ka PLC ke loaʻa i nā hōʻailona encoder a me nā sensor me ka ʻole o ka amplifier, no laila he aha ka leʻaleʻa o ka "kumu" a me ka "wai"? ʻO ka hoʻopuka wale nō o PLC e loaʻa nā manaʻo o "kumu" a me "leakage".

ʻOiaʻiʻo, koe wale nō ka PLC Kepanī, ʻaʻole pono i nā PLC ʻē aʻe ke hoʻohana i nā pōkole e like me "kumu" a me "drain", akā hiki ke hoʻohana pololei ʻia ʻo PNP a me NPN.

ʻO PNP kahi laina ākea haʻahaʻa haʻahaʻa, a ʻo NPN kahi laina ākea kiʻekiʻe. Inā pololei kēia pili, ʻaʻole ia he mea nui inā hoʻohuli ʻia nā manaʻo o ka "kumu" a me ka "wai". Eia nō naʻe, hewa kekahi manaʻo "loiloi maikaʻi a me ka loiloi maikaʻi ʻole", e hoʻohuli ʻia ka hōʻailona.

ʻO ka loiloi maikaʻi a me ka loiloi maikaʻi ʻole

Ma nā kaapuni ʻano PNP, aia ka pahu maʻamau o ka lako mana a me ka hōʻailona ma kahi haʻahaʻa o 0V. I ka haʻahaʻa haʻahaʻa o ka hoʻokomo ʻana, ʻaʻohe ʻokoʻa ʻokoʻa me ka pahu maʻamau, no laila ʻaʻohe hoʻonui hoʻololi hoʻololi hoʻopuka puka (ʻo ka helu helu 0). Aia wale nō ka mea hoʻokomo ma kahi kiʻekiʻe, aia kahi ʻokoʻa voltage me ka pahu maʻamau a ʻo kahi hōʻailona hoʻololi i hoʻonui ʻia i hoʻopuka ʻia ma kahi kiʻekiʻe. ʻO kēia ʻano kikohoʻe (ka helu kikohoʻe ʻo 1) ʻoi aku ka maikaʻi ke piʻi ka hōʻailona ma kahi kiʻekiʻe i kapa ʻia ʻo PNP positive logic.

Ma ke kaapuni NPN, aia ka pahu maʻamau o ka lako mana a me ka hōʻailona ma kahi kiʻekiʻe (ke ʻano o kēia kaapuni amplifier). Ke kiʻekiʻe ka hoʻokomo ʻana, ʻaʻohe ʻokoʻa uila ma waena o ka hoʻokomo a me ka hoʻopuka, no laila ʻaʻohe puka hōʻailona hoʻololi (ʻo ka helu kikohoʻe he 0). Aia wale nō ka mea hoʻokomo i kahi pae haʻahaʻa (e hana ana i ka funnel), aia kahi puka hōʻailona hoʻololi, a ʻo kēia hōʻailona he hopena maikaʻi (ka helu kikohoʻe ʻo 1) mode kikohoʻe ma kahi haʻahaʻa, i kapa ʻia ʻo NPN negative logic.