Te Whakamahinga o te PLC i roto i te Whakahaere Tukanga
I roto i te ao ahumahi hou, kei te tipu haere tonu te hiahia mō ngā pūnaha whakahaere pono, tere, me te ngāwari ki te whakawhanake. Me pupuri e ngā kamupene te kounga o ngā hua, me whakanui ake i te pai o te mahi, me te whakaiti i te wā whakatā o te whakaputanga. Ko tētahi o ngā hangarau e whakamahia whānuitia ana hei whakatutuki i ēnei hiahia ko te PLC (Programmable Logic Controller). Ko ngā PLC ngā "roro" o ngā raina whakaputa maha—te whakahaere i ngā mīhini, te aroturuki i ngā pūoko, me te whakahaere aunoa i te arorau tukanga. Ka matapakihia e tēnei tuhinga te whakamahinga o ngā PLC i roto i te whakahaere tukanga, ō rātou wāhanga matua , te āhua o tā rātou mahi, ō rātou painga, ngā wero, me ngā tauira o ā rātou tono i te mara.
1. He aha te PLC?
He taputapu whakahaere matihiko te PLC e ahu mai ana i te tukatuka iti, i hangaia mō ngā taiao ahumahi. He rerekē ki ngā rorohiko tuku iho, he mea hanga ngā PLC kia tū atu ki te wiri, ki ngā pāmahana tino kino, ki te puehu, me te pokanoa hiko. Ka whakakapia e ngā PLC ngā pūnaha whakahaere tuku iho e ahu mai ana i te whakawhitiwhiti (arorau whakawhitiwhiti), he uaua ki te whakarerekē, ā, me nui te waea e hiahiatia ana.
Ka taea te whakarite i ngā PLC ki te mahi i ngā mahi whakahaere maha, mai i ngā mahi māmā pēnei i te tīmata i te motuka i runga i ngā tohu pūoko, ki ngā tukanga uaua pēnei i te whakahaere i te pāmahana, te pēhanga, ngā rerenga whakaputa rānei e uru ana ki ngā wāhanga maha.
2. Te Tūranga o te PLC i roto i te Whakahaere Tukanga
Ko te whakahaere tukanga ko te mahi o te whakahaere i ngā taurangi tukanga (hei tauira, te pāmahana, te pēhanga, te taumata wai, te tere rere, te tere o te motuka) kia tutuki ai ngā uara e hiahiatia ana. Ko te PLC te kaiwhakahaere matua, arā:
1. Whiwhi tohu mai i ngā pūoko (whakauru) pērā i ngā pūoko tata, ngā pana rohe, ngā RTD/thermocouples, ngā mita rere, ngā tuku pēhanga, ngā pūoko taumata rānei.
2. Te tukatuka i ngā arorau/ngā kaupapa e hangai ana ki ngā tikanga whakauru, ngā pūwāhi tautuhinga, me ngā rauropi whakahaere.
3. Tukuna ngā whakahau ki ngā actuator (ngā putanga) pērā i ngā takirere solenoid, ngā motuka tīmatanga, ngā inverters/VFD, ngā whakamahana, ngā papu, ngā whakaoho rānei.
4. Tuhia me te whakawhitiwhiti raraunga ki ētahi atu pūnaha pēnei i te HMI (Human Machine Interface), te SCADA (Supervisory Control and Data Acquisition), te DCS rānei mā roto i ngā kawa whakawhitiwhiti ahumahi.
Mā ēnei āheinga, ka noho te PLC hei pūnaha tino nui hei pupuri i te ōritetanga o ngā tukanga me te pumau o te whakaputanga.
3. Ngā Wāhanga Matua o te PLC
I te nuinga o te wā, he maha ngā wāhanga nui o te PLC:
– PTM (Wāhanga Tukatuka Matua): Ka whakahaere i te whakahaerenga o te hōtaka me te whakatau kaupapa whakahaere.
– Pūtake Hiko: E whakarato ana i te pūtake hiko mō te waeine PLC.
– Wāhanga Whakauru: Ka whiwhi tohu matihiko/anarohiko mai i ngā pūoko. Ko te whakaurunga matihiko he ON/OFF te tikanga, ko te whakaurunga matihiko he ON/OFF. tohu anaro 4–20 mA, 0–10 V rānei.
– Wāhanga Putanga: Ka tuku tohu matihiko/anarohiko ki ngā kaiwhakahaere whakahaere.
– Mahara: Ka penapena i ngā hōtaka me te tukatuka raraunga.
– Wāhanga Whakawhitiwhiti Kōrero: Tautoko ana i ngā whatunga ahumahi pēnei i a Modbus, Profibus, Profinet, Ethernet/IP, CANopen, me ētahi atu.
I runga i ngā hiahia, ka taea e ngā PLC te noho hei waeine kiato (katoa-i-te-kotahi) he waeine wāhanga rānei ka taea te whakawhānui ngāwari mā te I/O.
4. Te Mahi a te PLC : Huringa Matawai
Ko te kaupapa o te mahi a te PLC he huringa matawai tere tonu:
1. Matawai Tāuru: Ka pānuihia e te PLC te tūnga o ngā tāuru katoa.
2. Matawai Papatono: Ka whakahaerehia e te PLC te arorau o te hōtaka mai i runga ki raro (i runga i te reo hōtaka).
3. Whakahōu Putanga: Ka whakahōu te PLC i te putanga e ai ki ngā hua o te hōtaka.
4. Te Whakahaere Whare/Te Whakawhitiwhiti Kōrero: Ka whakahaerehia e te PLC ngā tātaritanga, ngā whakawhitiwhiti kōrero whatunga, me ētahi atu mahi ā-roto.
Ka puta tēnei tukanga i roto i ngā mirihekona, nō reira ka taea e te PLC te urupare ki ngā huringa o ngā āhuatanga tukanga i te wā tonu.
5. Reo Hōtaka PLC
Ka whakaritea ngā PLC mā te whakamahi i te paerewa IEC 61131-3. Ko ētahi o ngā reo e whakamahia whānuitia ana ko:
– Kauwhata Arawhata (LD): Tino rongonui, he rite ki te ara iahiko whakawhiti. He pai mō te arorau motuhake.
– Kauwhata Poraka Mahi (FBD): Mā te whakamahi i ngā poraka mahi, e whakamahia ana mō te whakahaere anaro me te whakahaere tukanga.
– Kuputuhi Hanganga (ST): He rite ki tētahi reo hōtaka taumata-tiketike, he pai mō ngā rauropi uaua.
– Tūtohi Mahi Raupapa (SFC): He pai mō ngā tukanga raupapa pēnei i te puranga, te tākai rānei.
– Rārangi Tohutohu (IL): Ka iti haere te whakamahinga nā te mea kua tīmata te whakarērea.
Ko te whiriwhiringa o te reo ka whakarerekētia i te uauatanga o te tukanga me ngā tikanga a te tīma hangarau.
6. PLC mō te Mana Motuhake me te Mana Tonu
Ka taea te wehewehe i te whakamahinga o ngā PLC i roto i te whakahaere tukanga ki ngā momo e rua:
a) Mana Motuhake
Ka mahi te mana motuhake ki ngā tikanga ON/OFF. Hei tauira:
– Ka tahuri te kaikawe ina kitea e te pūoko tētahi taonga.
– Ka whakahohe i te papu ina iti te taumata o te tāke.
– Ka maukati i te raka haumaru ina tuwhera te tatau o te mīhini.
He tino kaha ngā PLC ki te whakahaere motuhake nā te mea he ngāwari te whakatinana me te whakarerekē i te arorau rua.
b) Mana Whakahaere Tonu (Mana Whakahaere Analog/Tukanga)
Ko te whakahaere tonu he taurangi ā-ira, ā, me whakamahi i tētahi pūnaha pēnei i te PID (Proportional-Integral-Derivative). Hei tauira:
– Whakahaerehia te pāmahana o te oumu mā te whakamahi i te pūoko whakamahana me te pūoko werawera.
– Whakahaerehia te pēhanga o te mamaoa mā te whakamahi i te takirere whakahaere.
– Kia mau tonu te taumata o te tāke mā te whakahaere i te papu, i te takirere rānei.
He maha ngā PLC hou kua whakauru kē i ngā mahi PID, ka taea rānei te whakauru atu ki tētahi kōwae whakahaere motuhake.
7. Te whakaurunga PLC ki te HMI me te SCADA
I te mara, kāore i te maha ngā PLC e mahi takitahi. He maha ngā wā ka honoa ngā PLC ki:
– HMI hei whakaatu i te tūnga o te mīhini, ngā whakaoho, ngā tawhā tautuhinga, me te mana whakahaere ā-ringa/aunoa. Ka taea e ngā kaiwhakahaere te aroturuki i ngā tukanga me te mahi i ngā mahi me te kore e whakatuwhera i te papatohu whakahaere.
– SCADA mō te aroturuki i ngā waeine maha, te tuku pūrongo, te au o ngā raraunga, me te whakaurunga ki ngā pūnaha whakaputa whānui. Ka taea hoki e SCADA te whakahaere mai i te rūma whakahaere.
Ka whakapai ake tēnei whakaurunga i te tirohanga o ngā tukanga, ka tere ake te rapurongoā, ā, ka tautoko hoki i te whakatau kaupapa e ahu mai ana i ngā raraunga.
8. Ngā Painga o te Whakamahi i te PLC
Ko ētahi o ngā painga o te PLC i roto i te whakahaere tukanga ko:
1. Ngāwari, ngāwari hoki te whakarerekē: Ka taea te whakarerekē i ngā arorau mā te hōtaka, me te kore e hiahiatia te wetewete i ngā taura pērā i te pūnaha tuku.
2. Pono mō ngā taiao ahumahi: I hangaia hei ātete i ngā raruraru hiko me ngā āhuatanga mahi taumaha.
3. Te tere ake o te tātaritanga me te rapurongoā: He maha ngā PLC e whakarato ana i ngā tohu tūnga, ngā rangitaki hapa, me te aroturuki ipurangi.
4. Āhuatanga Tauine: Ka taea te tāpiri i te I/O ina hiahiatia (ina koa ko ngā PLC modular).
5. Tautoko ana i te whakawhitiwhiti kōrero whānui: He ngāwari te whakauru atu ki ngā pūoko atamai, VFD, HMI, SCADA, me ngā pūnaha MES/ERP.
9. Ngā Wero me ngā Mea hei Tūpato
Ahakoa ōna painga, he wero anō hoki kei te whakatinanatanga o te PLC:
– Ka uaua te tiaki i tētahi pūnaha mēnā he hoahoa hōtaka ngoikore. He mea nui te hanganga o te hōtaka, te whakaingoa i ngā tohu, me te tuhi tuhinga.
– Te whakawhirinaki ki te pūkenga o te tohunga hangarau: Me mārama ki te hiko, ki ngā taputapu, me te hōtaka.
– Haumarutanga Ipurangi: He ngoikore ngā PLC whatunga ki te whakaeke. Kei te piki haere te hiranga o ngā mahi pēnei i te wehewehenga whatunga, te whakahaere urunga, me te whakahaere papaki.
– Kōwhiringa taputapu tika: Mā te kōwhiringa hē o te kaha I/O, te tere matawai, te kōwae anarau rānei ka raru te mahi a te mana whakahaere.
Nō reira, me whai whakaaro te whakamahere pūnaha whakahaere ki ngā hiahia o ngā tukanga o nāianei me ngā whanaketanga pea ā muri ake nei.
10. Ngā Tauira o ngā Whakamahinga PLC i roto i te Ahumahi
He whānui rawa te whakamahinga o te PLC, hei tauira:
– Ahumahi hangahanga: Whakahaere mīhini CNC, raina huihuinga, karetao, me ngā pūnaha kawe.
– Ahumahi kai me te inu: puranga, whakaranu, CIP (horoi-ki-te-wāhi), whakahaere pāmahana pasteurization.
– Ahumahi matū: te whakahaere takirere, ngā papu, ngā tauhohenga, me ngā pūnaha haumaru raka.
– Te maimoatanga wai: te whakahaere i ngā papu, ngā pupuhi, te inenga matū, me ngā taumata o te puna wai.
– Pūngao me ngā ratonga: te whakahaere i ngā pūwero, ngā pūwhakakoi, me te tohatoha pūngao.
I ngā wā maha, ko ngā PLC te ngākau o te aunoatanga nā te mea ka taea e rātou te whakahaere i te arorau raupapatanga, te whakahaere anaro, me te whakawhitiwhiti kōrero i waenga i ngā pūnaha i roto i te tūāpapa kotahi.
Whakamutunga
Kua noho ngā PLC hei hangarau matua i roto i te whakahaere tukanga ahumahi nā te mea he pono, he ngāwari, he ngāwari hoki te whakauru. Mā ngā PLC, ka taea e ngā kamupene te whakahaere aunoa i ngā mahi, te whakapai ake i te kounga o te mahi, te whakateretere i te whakaputa, me te whakahaere i te aroturuki me te rapurongoā. Heoi, ko te angitu o te whakatinanatanga o te PLC ehara i te mea ko te taputapu anake engari ko te hoahoa pūnaha, te kounga hōtaka, te tuhinga, me ngā rautaki tiaki. Mā te whakamahere tika, ka taea e ngā PLC te pā nui ki te whai huatanga me te pumau o te tukanga puta noa i ngā rāngai ahumahi rerekē.
Ki te hiahia koe, ka taea e au te āwhina i a koe ki te waihanga i tētahi putanga hangarau ake o tō tuhinga (hei tauira, te matapaki i ngā tauira arawhata, te whakatikatika PID, te hoahoa whatunga, ngā rangahau take whakahaere taumata/pāmahana rānei) te whakarerekē rānei i tō momo tuhituhi mō ngā mahi o te kāreti me ngā pūrongo ahumahi.
