Fahimtar Thermocouples a cikin HVAC Systems

Thermocouples sune mafi yawan na'urorin firikwensin zafin jiki a cikin tsarin dumama, iska, da kuma iska mai sanyaya. Suna dogara ne akan tasirin Seebeck: lokacin da aka dumama ko sanyaya mahaɗin ƙarfe biyu ba iri ɗaya ba, ƙarfin lantarki mai daidaita da bambancin zafin jiki ya bayyana tsakanin mahaɗar. Wannan ƙaramin siginar millivolt ana karanta ta ta mai sarrafawa don ƙayyade zafin jiki a mahaɗin aunawa.

A aikace-aikacen HVAC, thermocouples suna taka muhimmiyar rawa da dama:

  • Fitar wuta a cikin murhun gas: A thermocouple sanya a cikin jirgin sama harshen wuta samar da wani halin yanzu da rike da gas bawul bude. Idan harshen wuta ya fita, da ƙarfin lantarki ya sauko da bawul rufe, hana unburned gas daga tserewa.
  • Sarrafa zafin jiki a cikin famfunan zafi da na'urorin daidaita iska: Thermocouples suna lura da yanayin zafin jiki na layin refrigerant, yanayin zafin jiki na coil, da iska ta kewaye don inganta inganci.
  • Kariya ta sama da zafin jiki: A cikin masu sanyaya wutar lantarki da masu matsewa, thermocouples suna haifar da kashewa na aminci lokacin da yanayin zafi ya wuce iyakar aminci.
  • Fitar da tsarin: FIT: 1 Fitaccen fasaha na sabis yana amfani da karatun thermocouple don gano matsalolin cajin refrigerant, matsalolin iska, ko ɓangarorin da suka gaza.

Yawancin nau'ikan thermocouples suna da mahimmanci ga yanayin HVAC. Nau'in K (chromel-alumel) yana ba da fadi da kewayon (−200 °C zuwa 1260 °C) da kuma daidaito mai kyau don aikace-aikacen tanda. Nau'in J (ƙarfe-matsakaici) yana da yawa a cikin tsofaffin kayan aiki. Nau'in T (ƙarfe-matsakaici) ya fi kyau a cikin ƙananan yanayin sanyaya. Mafi ƙarancin amfani amma mai amfani a cikin manyan yanayin dafa abinci na kasuwanci shine nau'in N (nicrosil-nisil), wanda ya fi ƙarfin oxidation fiye da nau'in K. Zaɓin nau'in da ya dace don aikace-aikace na musamman yana tabbatar da karatun abin dogaro da tsawon rayuwar firikwensin.

Yadda Mai Gudanarwa Yake Fassarar Siginan Thermocouple

Masu sarrafa HVAC na zamani sun haɗa da biyan kuɗi na haɗin sanyi (CJC), wanda ke auna zafin jiki a tashoshin sarrafawa kuma yana daidaita lissafin ƙarfin lantarki daidai. Ba tare da CJC ba, karatun thermocouple zai kasance game da yanayin zafin jiki na ƙarshe maimakon cikakke. Wasu masu sarrafawa na musamman suna amfani da algorithms na layi don gyara ɗan rashin layi na fitowar thermocouple. Fahimtar wannan hulɗar yana taimaka wa masu fasaha su gano ƙididdigar karatun da suka samo asali daga mai sarrafawa maimakon firikwensin.

Mafi Kyawun Ayyuka don Gudanar da Thermocouples

Yin amfani da thermocouples daidai yana shafar daidaito na aunawa da kuma amincin tsarin.

Yin Bincike da Tsabtace a Kai a Kai

Thermocouples aiki a matsananci yanayi shafar da konewa byproducts, turɓaya, zafi, da kuma matsanancin zafin jiki.

  • Rushewa ko oxidation a kan bincike da kuma haɗa wayoyi.
  • Ƙarƙashin ƙarancin ƙarfe na iya haifar da gajeren ƙarfe.
  • Kayan aiki mai sassaucin ra'ayi wanda ke canza matsayin na'urar daukar hoto dangane da matsakaiciyar da aka auna.
  • Ƙarƙashin ruwa, mai, ko kuma ɓarnar da ke rufe haɗin kuma yana rage lokacin amsawa.
  • Rashin launi na shea, wanda zai iya nuna nuna haɗuwa da yanayin zafi fiye da iyakar ƙayyadaddun.

Ya kamata a yi tsabtace tare da labule mai laushi, mara laushi da kuma mai narkewa mai laushi kamar isopropyl barasa idan na'urar ba ta cikin kewayawa mai rai. Guji kayan aiki masu lalata ko sinadarai masu haɗari waɗanda zasu iya lalata katako na ƙarfe ko haɗuwa. Don na'urorin firgici a cikin tanda, a hankali goge binciken tare da takarda mai laushi (600 grit) don cire oxidation, sannan a tsabtace tare da labule mai bushe.

Hanyoyin Da Ya Dace na Shiga

Kuskuren shigarwa sune manyan dalilan rashin nasarar thermocouple da rashin daidaito. Bi wadannan jagororin:

  • FLT:0]] zurfin nutsewa daidai: Dole ne a nutsar da mahaɗin a cikin matsakaici (ruwan iska, wuta, ko ruwa). Mafi ƙarancin zurfin nutsewa sau 10 na diamita na bincike shine misali don firikwensin da ke iyakance iska.
  • A cikin tashoshin bututu ko bututu, shigar da thermocouple don haka haɗuwa ta kasance mai madaidaiciya ga jagoran kwarara don amsa mafi sauri. A cikin tanda, ya kamata a sanya thermocouple kai tsaye a cikin wutar matukin jirgi a tsawo da aka ƙayyade ta masana'anta.
  • Tsarin shigarwa: Yi amfani da kayan matsi, adaftan madauri, ko shirye-shiryen matattarar da aka ɗora don hana motsi saboda rawar jiki.
  • Wire routing: Ka kiyaye wayoyin tsawaita wutar lantarki daga wayoyin ƙarfin lantarki da kuma hanyoyin tsangwama na lantarki. Ana ba da shawarar igiyar da aka yi da biyu ko kuma katanga don dogon gudu. Ka guji lankwasawa mai kaifi wanda zai iya gajiyar da waya.
  • Kwankwaso na haɗin sanyi: Yawancin masu sarrafa HVAC na zamani suna da CJC. Idan kuna amfani da mai auna thermocouple mai zaman kansa, tabbatar da haɗin tunani yana a sanannen zafin jiki (misali, wanka mai ƙanƙara ko toshewar ajiya). Ana samun kayayyaki na CJC da aka shigar a filin don masu sarrafawa na gargajiya.

Abubuwan da Za a Yi da Kuma Zaɓin Abubuwan da Za a Yi

Zaɓin da bai dace ba zai iya sa a yi amfani da wutar lantarki da ke yin amfani da wutar lantarki ba, ko kuma ya sa a yi amfani da wutar lantarki da ke yin amfani da wutar lantarki da ke yin amfani da wutar lantarki.

  • Yanayin zafin jiki: Zaɓi nau'in thermocouple wanda yawan zafin jiki na ci gaba da aiki ya fi matsakaicin zafin jiki na tsarin da ake tsammani da aƙalla 50 ° C. Don na'urorin firgice na wuta a cikin tanda na gas, Nau'in K shine misali saboda yana jure maimaitawar zafin jiki har zuwa 1000 ° C.
  • Kayan shinge: (FLT: 0) Kayan shinge: (FLT: 1) Karfe mai bakin karfe (304 ko 316) ya zama ruwan dare ga amfani da HVAC na gaba ɗaya. Don yanayin lalata (misali, masu sanyaya wuraren wanka ko wuraren dafa abinci na masana'antu), Inconel ko Hastelloy shinge suna ba da juriya mafi kyau. Don wuraren sarrafa abinci, ana iya buƙatar shinge mai ƙimar abinci.
  • Ƙasa vs. Ƙasa: Ƙasa haɗin (wayaje da aka walda zuwa sheath) suna amsawa da sauri amma na iya zama masu saurin ƙwanƙwasawa a cikin yanayin lantarki mai hayaniya. Ƙasa haɗin ƙasa suna kawar da ƙwanƙwasa ƙasa kuma ana fifita su don tsarin sarrafawa na daidaito. Nau'in ƙarancin ƙasa kuma suna samar da keɓewar lantarki, wanda ke da mahimmanci lokacin da thermocouple ke tuntuɓar mai kai tsaye.
  • A cikin yanayin zafi mai zafi, amfani da filastik na fiberglass ko na keramic. PVC mai rufi yana da kyau kawai har zuwa 105 ° C kuma bai kamata a sanya shi kusa da masu ƙonawa ba. Silicone insulation (har zuwa 200 ° C) shine kyakkyawan matsakaici don aikace-aikacen HVAC da yawa.
  • Nau'in mahaɗin: Yi amfani da mahaɗan da aka yi don takamaiman gami na thermocouple don kauce wa haɗuwa da ƙarfe biyu waɗanda ke haifar da ƙarin ƙarfin lantarki.

Yana da kyau a tuntuɓi ƙayyadaddun masana'antun kayan aikin HVAC ko mai ba da haska mai suna lokacin zaɓar thermocouples na maye gurbin. Yin amfani da nau'in da ba daidai ba na iya haifar da kurakuran karatu na digiri da yawa da kuma rashin garantin kayan aiki. Don cikakken jagora, jagorar zaɓin thermocouple na Omega Engineering na FLT:1 yana ba da cikakken teburin haɗuwa da yanayin zafin jiki.

Ka Guji Rashin Yanki da Kuma Matsalolin Yanki

Thermocouples kayan aiki ne masu mahimmanci. Matsin jiki na iya canza tsarin lu'ulu'u na ƙarfe, yana haifar da karkatar da ma'auni ko gazawar.

  • Aikin: Kullum ka riƙe jikin binciken ko mai haɗawar sanyi. Kada ka taɓa jan wayoyi. Fitar da binciken zai iya yin karkacewar haɗuwa.
  • Vibration: Yi amfani da tsawan tsawan tsawan tsawan tsawan tsawan tsawan tsawan kusa da injuna, kwampreso, ko magoya baya. Saurin tsawan tsawan zai iya gajiyar da wayoyi a inda suka fita daga sheqa. A cikin ɗakunan rufin da aka fallasa zuwa sautin iska, yi la'akari da amfani da madauri a cikin waya don shawo kan motsi.
  • FLT:0]]Thermal shock: Ka guji canje-canje masu saurin zafin jiki waɗanda suka wuce ƙimar ramp da aka ƙayyade ta masana'anta. Don thermocouples na tanda, bari firikwensin ya sanyaya a hankali bayan rufe tsarin. Saurin sanyaya daga 1000 ° C zuwa zafin jiki na daki na iya haifar da karkacewa.
  • A cikin yanayin da ke da chlorine, sulfur, ko wasu iskar gas mai tsanani, yi la'akari da amfani da garkuwa mai kariya ko shea mai tsananin ƙarfe. Ko da gajeren lokaci na haɗuwa da hydrogen sulfide na iya lalata nau'in thermocouple na Nau'in K. Don masu dumama wuraren waha, nau'in K tare da shea mai bakin karfe na iya gazawa cikin watanni; ana ba da shawarar shea mai Hastelloy.
  • A cikin tsarin HVAC na masana'antu tare da hasken ultraviolet germicidal (UVGI) don maganin kashe iska, haɗarin UV na iya lalata keɓewar PVC. Yi amfani da igiyar gilashi ko teflon mai keɓewa kusa da fitilun UV.

Ƙididdiga da Tabbatar da

Ko da sababbin thermocouples na iya kaucewa daga daidaitaccen layin su da ±2 ° C ko fiye. daidaitaccen daidaitawa yana tabbatar da cewa ƙarfin lantarki ya dace da yanayin zafi na ainihi. Cibiyar Nazarin Kasa da Fasaha (NIST) ta samar da ƙa'idodin daidaitawa don na'urori masu auna sigina na masana'antu.

Don aikin filin HVAC, hanya mai amfani ita ce:

  • A cikin yanayin zafi, ana iya amfani da matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar matattarar
  • Lambar shekara-shekara: aika da madaidaitan thermocouples da ake amfani da su wajen sarrafa matakai masu mahimmanci zuwa dakin gwaje-gwaje mai inganci kowane watanni 12.
  • Logici mai sauyawa filin: FLT:1]] Yawancin masu kula da HVAC suna da daidaitawar daidaitawa. Idan thermocouple koyaushe yana karanta 2 °C ƙasa, mai kula zai iya amfani da ma'aunin gyara a matsayin matakin wucin gadi har sai an maye gurbin firikwensin.
  • Bayanan: FLT:1] Ci gaba da yin rikodin kwanakin daidaitawa, karatun, da duk wani gyare-gyare da aka yi. Wannan tarihin yana taimakawa wajen gano jujjuyawar firikwensin a tsawon lokaci da tsara sauyawar mai aiki.
  • Flt:0: Don aikace-aikace masu mahimmanci (misali, sanyaya cibiyar bayanai), shigar da thermocouple na biyu a daidai da firikwensin farko. Idan karatun biyu suka bambanta, yana nuna rashin nasarar firikwensin maimakon canjin tsari.

Don cikakkun hanyoyin daidaitawa, duba jagorar daidaitawa na thermocouple na NIST .

Tsarin Digital vs. Tsarin Thermocouple na analog

Yawancin tsarin HVAC na zamani suna amfani da na'urorin firikwensin zafin jiki na dijital (DS18B20, NTC thermistors) don sabbin kayan aiki, amma thermocouples suna ci gaba da kasancewa masu mahimmanci a cikin yanayin zafin jiki mai yawa da yankunan yanayi mai matsananci. Lokacin da ake gyara ko haɓaka, masu fasaha na iya haɗuwa da tsarin hybrid inda thermocouple ke ciyar da mai watsa dijital wanda ke fitar da siginar 4-20 mA ko Modbus. Fahimtar tsarin jujjuyawar yana da mahimmanci: mai watsawa ya haɗa da CJC da layi, kuma daidaitattun sa ya dogara da thermocouple da na'urar lantarki. Yin amfani da mai watsawa mai inganci daga alamomi kamar HoneywellFLT: 1]] na iya haɓaka daidaitattun tsarin gaba ɗaya idan aka kwatanta da haɗin kai tsaye zuwa mai sarrafawa.

Matsaloli da Suka Shafi Ko Kuma Yadda Za a Warware Matsaloli

Duk da mafi kyawun ayyuka na sarrafawa, thermocouples na iya yin kasawa ko samar da karatun rashin daidaito.

  • Budewa (rashin aiki a waya ko mahaɗin).
  • Ƙananan hanyoyi (ƙananan ƙarfe a kan igiyoyi ko lalacewar rufi).
  • Ruwa saboda oxidation ko gurɓatawar mahaɗin.
  • Ƙarƙashin ƙasa da aka haifar ta hanyar hanyoyi masu yawa a cikin tsarin.
  • Ƙarƙashin haɗin ko kuma tashoshin da ba su da ƙarfi.
  • Rashin daidaituwa na nau'in thermocouple (misali, firikwensin nau'in J a cikin kewayawar nau'in K).
  • Juyawa polarity na fadada waya, wanda ya haifar da m ƙarfin lantarki karatu ko manyan kurakurai.

Gano Masu Rashin Gaskiya na Wutar Lantarki

Alamun da ke nuna cewa thermocouple na iya yin rashin nasara sun hada da:

  • Tsarin bai kunna ba ko kuma harshen wuta ya kashe lokaci-lokaci (kwakwalwar).
  • Ƙididdigar zafin jiki da ke da kuskure (misali, nuni yana nuna 500 °C a cikin ɗakin 20 °C).
  • Mai kula da wutar lantarki yana kunna ƙararrawa na yawan zafin jiki duk da yanayin da ya dace.
  • Amsa mai jinkiri ko rashin daidaituwa ga canje-canje a zafin jiki.
  • Karatun da ke motsawa sama a cikin sa'o'i da yawa zuwa kwanaki (oxidation).

Idan ka ga waɗannan alamun, ka fara duba hoton da ke jikinsa da kuma wayoyinsa don ka ga ko an cire shi ko kuma an yi masa fasa, ko kuma an yi masa lahani a ƙarshen ƙofar.

Jagorar Gyara Matsaloli Mataki-mataki

  1. Duba mai kula ko mita: Kashe thermocouple kuma yi amfani da sanannen thermocouple ko mai kwaikwayon juriya (misali, 0.8 mV don Nau'in K a 20 °C) don tabbatar da cewa kewayon shigarwar yana aiki.
  2. Matakan juriya: Yin amfani da multimeter saita zuwa ohms, auna a fadin thermocouple tashoshin a sanyi karshen. A na yau da kullum thermocouple nuna sosai low juriya (fewan ohms). A bude kewaye karanta m; wani gajeren karanta kusa da sifili. Don dogon runs, hada da tsawo waya juriyaya yawanci 1-2 ohms da 100 feet for 24 AWG.
  3. A cikin yanayin zafi mai zafi a sanannen zafin jiki (misali, zafin jiki na ɗaki), auna fitarwar millivolt tare da mai auna tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin tsananin ts
  4. FLT:0]]Gano madaukai na ƙasa: Auna ƙarfin lantarki tsakanin garkuwar thermocouple ko mara kyau waya da ƙasa ƙasa. Fiye da 'yan millivolts AC yana nuna madauki na ƙasa wanda zai iya buƙatar keɓewa. Idan karatun ya wuce 100 mV AC, thermocouple na iya tuntuɓar mai gudanarwa mai ƙarfi kashe tsarin nan da nan.
  5. FLT:0]]Saki masu haɗawa: Masu haɗawa da thermocouple (ƙananan ko misali) ya kamata su dace da nau'in waya. Hada nau'in K da nau'in J masu haɗawa na iya haifar da kurakurai na 10 ° C ko fiye. Tabbatar cewa ba a musanya wayoyin mai kyau da mara kyau ba.
  6. Yi gwajin zafi: Ka riƙe ƙwanƙolin binciken a hannunka (kimanin 35 ° C) ko kusa da bindigar zafi (da hankali, zauna a ƙasa da 200 ° C) kuma ka kalli canjin karatu. Amsar jinkiri (fiye da dakika 5 don isa ga ƙimar kwanciyar hankali) tana ba da shawarar gurɓata ko haɗuwa mai ƙyama.
  7. FLT:0]] Duba don haɗin kai: Sanya waya a hankali a tsawonsa. Idan karatun ya tsallake ko ya tafi sifili, akwai waya ta karye ko haɗin da ya ɓace a cikin keɓewa.

Don cikakken jagorar gyara matsala, jagorar gyara matsala na thermocouple na Omega Engineering ya ba da cikakkun yanayi da zane-zane na waya.

Lokacin da za a maye gurbin da kuma gyara

A mafi yawan aikace-aikacen HVAC, ana ɗaukar thermocouples a matsayin kayan amfani. Idan an lalace na'urar daukar hoto bayan tsaftace farfajiyar ko kuma idan mahaɗin ya yi karkace fiye da haƙuri mai karɓa (±0.75% na karatu don ƙididdigar misali), maye gurbin shine mafi aminci da mafi kyawun zaɓi. Gyara thermocouple ta hanyar sake walda mahaɗin yana yiwuwa a cikin yanayin dakin gwaje-gwaje, amma ba a taɓa samun dalili a filin saboda farashin maye gurbin yana da ƙaranci (yawanci $ 10 - $ 50) kuma ba za a iya tabbatar da daidaitawar na'urar daukar hoto ba tare da sake daidaitawa ba. Koyaushe kiyaye wasu ma'aunin thermocouples na nau'in da ya dace a kan motar sabis.

Nasihu na Tsaro da Kuma Ayyuka don Masu Fasaha na HVAC

Yin aiki tare da thermocouples a cikin tsarin HVAC na rayuwa yana bukatar kulawa:

  • Fitar da wutar lantarki kafin maye gurbin thermocouples ko tsaftacewa a cikin tsarin lantarki. Ko da ƙananan ƙarfin lantarki thermocouple circuits iya haifar da arcs idan aka gajarta.
  • Yi amfani da kayan kariya na sirri (PPE) lokacin aiki a kusa da wurare masu zafi ko wuta.
  • A lokacin da kake duba thermocouples na tanda, ka ba da lokacin sanyaya. Binciken da ƙarfe mai kewaye zasu iya riƙe zafi da ya isa ya haifar da ƙonawa. Yi amfani da thermometer mara lamba don tabbatar da cewa farfajiya ta faɗi ƙasa da 50 ° C kafin aiki.
  • Kada ku maye gurbin nau'in thermocouple ba tare da tabbatar da jituwa tare da mai kula da shi ba. Nau'in da ba daidai ba zai iya haifar da karatun da ba daidai ba wanda zai haifar da ɓarnatar da makamashi ko aiki mara lafiya.
  • FLT:0 Labaran wayoyin tsawo a lokacin maye gurbin don kiyaye polarity. Juyawa madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaidaicin madaida
  • A lokacin da kake matsawa matattarar matsin lamba, bi takamaiman ƙayyadaddun kayan aikin masana'anta.
  • Yi amfani da kayan aikin cire waya masu kyau don kauce wa lalata mai jagora. Waya mai lalatawa yana haifar da raunin da zai iya karyawa a ƙarƙashin rawar jiki.
  • Bayyana duk canje-canje a cikin tsarin log, gami da sabon nau'in firikwensin, ranar daidaitawa, da duk wani daidaitawar da aka yi.

Ƙarshen

Thermocouples sune doki marasa kyau na auna zafin jiki a cikin tsarin HVAC. Ta hanyar fahimtar ƙa'idodin aiki, zaɓar nau'in da ya dace da kayan don kowane aikace-aikace, da bin ƙa'idodin sarrafawa, shigarwa, da daidaitawa, masu fasaha na iya haɓaka ƙimar tsarin, hana lokacin kashewa mai tsada, da haɓaka aminci. Bincike na yau da kullun da saurin gyara matsalolin gama gari suna kiyaye na'urori masu auna firikwensin suna yin aiki a cikin haƙuri na shekaru. Jagororin da aka tsara a nan suna lalata kyawawan ayyukan masana'antu da shawarwarin masana'antu zuwa matakai masu aiki waɗanda za'a iya amfani dasu a kowane yanayin HVAC na mazauni ko na kasuwanci.

Don ƙarin karatu game da zaɓin firikwensin da ƙirar tsarin, littafin ASHRAE HVAC Systems and Equipment FLT:1 ya ƙunshi shafuka masu iko akan firikwensin zafin jiki. Bugu da ƙari, shafin yanar gizon FLT:2 Honeywell Building Technologies FLT:3 yana ba da bayanin aikace-aikace na musamman don kula da lafiyar tanda da haɗin thermocouple.