Abokai da yawa sun yi tambaya sau da yawa ko wutar lantarki ta poe ta tabbata?Menene mafi kyawun kebul don samar da wutar lantarki?Me yasa ake amfani da maɓallin waƙa don kunna kyamarar har yanzu babu nuni?da sauransu, a gaskiya, waɗannan suna da alaƙa da asarar wutar lantarki na POE, wanda ke da sauƙin yin watsi da aikin.
1. Menene wutar lantarki na POE
PoE yana nufin watsa bayanai don wasu tashoshi na tushen IP (kamar wayoyin IP, APs masu samun damar shiga mara waya ta LAN, kyamarori na cibiyar sadarwa, da dai sauransu) ba tare da yin wani canje-canje ga ababen more rayuwa na Ethernet Cat.5 na cabling ba.A lokaci guda kuma, tana iya samar da fasahar samar da wutar lantarki ta DC don irin waɗannan na'urori.
Fasahar PoE na iya tabbatar da aiki na yau da kullun na cibiyar sadarwar data kasance yayin tabbatar da tsaro na kebul ɗin da aka tsara, da kuma rage farashin.
Cikakken tsarin PoE ya haɗa da sassa biyu: kayan aikin samar da wutar lantarki da kayan aikin karɓar wutar lantarki.

Kayan Kayan Wutar Lantarki (PSE): Maɓallai na Ethernet, masu amfani da hanyar sadarwa, cibiyoyi ko wasu na'urori masu sauya hanyar sadarwa waɗanda ke tallafawa ayyukan POE.
Na'ura mai ƙarfi (PD): A cikin tsarin kulawa, galibi kyamarar cibiyar sadarwa ce (IPC).
2. POE wutar lantarki misali
Sabon ma'aunin duniya na IEEE802.3bt yana da buƙatu guda biyu:
Nau'i na farko: Daya daga cikinsu shi ne cewa ana bukatar karfin fitarwa na PSE ya kai 60W, karfin da zai kai na'urar karbar wutar ita ce 51W (ana iya gani daga teburin da ke sama cewa wannan shi ne mafi karancin bayanai), sannan Rashin wutar lantarki shine 9W.
Nau'i na biyu: ana buƙatar PSE don cimma ƙarfin fitarwa na 90W, ƙarfin da zai kai na'urar karɓar wutar lantarki shine 71W, asarar wutar kuma shine 19W.
Daga sharuddan da ke sama, za a iya sanin cewa da karuwar wutar lantarki, hasarar wutar ba ta yi daidai da na wutar lantarki ba, amma hasarar tana kara girma, to ta yaya za a iya kididdige asarar PSE a aikace?
3. POE wutar lantarki
Don haka bari mu kalli yadda ake kididdige asarar wutar lantarki a junior high school physics.
Dokar Joule kwatanci ne mai ƙididdigewa na jujjuya makamashin lantarki zuwa zafi ta halin yanzu.
Abin da ke ciki shine: zafin da ake samu ta hanyar wucewa ta halin yanzu yana daidai da murabba'in halin yanzu, daidai da juriya na mai gudanarwa, kuma daidai da lokacin da aka kunna shi.Wato, yawan amfani da ma'aikata da aka samar a cikin tsarin lissafin.
Maganar lissafi na dokar Joule: Q=I²Rt (wanda ya dace da duk da'irori) inda Q shine ƙarfin da ya ɓace, P, I shine halin yanzu, R shine juriya, kuma t shine lokacin.
A cikin ainihin amfani, tun lokacin da PSE da PD ke aiki a lokaci guda, asarar ba ta da dangantaka da lokaci.Ƙarshe shine cewa asarar wutar lantarki na kebul na cibiyar sadarwa a cikin tsarin POE ya dace da murabba'in na yanzu da kuma daidai da girman juriya.A taƙaice, don rage yawan wutar lantarki na kebul na cibiyar sadarwa, ya kamata mu yi ƙoƙari mu sanya halin yanzu na waya ya zama ƙarami da juriya na kebul na cibiyar sadarwa.Daga cikin su, mahimmancin rage halin yanzu yana da mahimmanci.
Sannan bari mu kalli takamaiman ma'auni na ƙa'idodin ƙasashen duniya:
A cikin ma'auni na IEEE802.3af, juriya na kebul na cibiyar sadarwa shine 20Ω, ƙarfin fitarwa na PSE da ake buƙata shine 44V, na yanzu shine 0.35A, kuma asarar wutar lantarki shine P=0.35*0.35*20=2.45W.
Hakazalika, a cikin daidaitattun IEEE802.3at, juriya na kebul na cibiyar sadarwa shine 12.5Ω, ƙarfin da ake buƙata shine 50V, na yanzu shine 0.6A, kuma asarar wutar lantarki shine P=0.6*0.6*12.5=4.5W.
Duk ma'auni biyu ba su da matsala ta amfani da wannan hanyar lissafi.Koyaya, lokacin da aka kai ma'aunin IEEE802.3bt, ba za a iya ƙididdige shi ta wannan hanyar ba.Idan ƙarfin lantarki shine 50V, ƙarfin 60W dole ne ya buƙaci halin yanzu na 1.2A.A wannan lokacin, asarar wutar lantarki shine P = 1.2 * 1.2 * 12.5 = 18W, rage asarar zuwa PD Ƙarfin na'urar shine kawai 42W.
4. Dalilan asarar wutar lantarki na POE
To menene dalili?
Idan aka kwatanta da ainihin abin da ake buƙata na 51W, akwai ƙarancin ƙarfin 9W.To menene ainihin ke haifar da kuskuren lissafin.
Bari mu sake duba ginshiƙi na ƙarshe na wannan jadawali na bayanan, kuma mu lura da kyau cewa na yanzu a cikin ainihin ma'aunin IEEE802.3bt har yanzu yana 0.6A, sannan kuma mu kalli wutar lantarki ta karkace, muna iya ganin nau'i-nau'i na murɗaɗɗen wutan biyu. Ana amfani da wadata (IEEE802.3af, IEEE802. 3at yana aiki da nau'i-nau'i na nau'i-nau'i nau'i-nau'i) Ta wannan hanyar, ana iya ɗaukar wannan hanya a matsayin layi na layi daya, halin yanzu na dukan da'irar shine 1.2A, amma asarar duka shine sau biyu. na biyu nau'i-nau'i na karkatacciyar wutar lantarki.
Saboda haka, asarar P=0.6*0.6*12.5*2=9W.Idan aka kwatanta da nau'i-nau'i 2 na igiyoyi masu karkatarwa, wannan hanyar samar da wutar lantarki tana adana 9W na wutar lantarki, ta yadda PSE zai iya sa na'urar PD ta sami wuta lokacin da ƙarfin fitarwa ya kasance 60W kawai.Ikon iya isa 51W.
Sabili da haka, lokacin da muka zaɓi kayan aikin PSE, dole ne mu mai da hankali ga rage halin yanzu da kuma ƙara ƙarfin wutar lantarki kamar yadda zai yiwu, in ba haka ba zai iya haifar da asarar wutar lantarki mai yawa.Ana iya amfani da ikon kayan aikin PSE kadai, amma ba a samuwa a aikace.
Na'urar PD (kamar kyamara) tana buƙatar 12V 12.95W don amfani.Idan aka yi amfani da 12V2A PSE, ƙarfin fitarwa shine 24W.
A cikin ainihin amfani, lokacin da na yanzu shine 1A, asarar P=1*1*20=20W.
Lokacin da halin yanzu shine 2A, asarar P=2*2*20=80W,
A wannan lokacin, mafi girman halin yanzu, mafi girman hasara, kuma yawancin iko an cinye shi.Babu shakka, na'urar PD ba za ta iya karɓar ikon da PSE ke watsawa ba, kuma kyamarar ba za ta sami isasshen wutar lantarki ba kuma ba za ta iya aiki kullum ba.
Wannan matsala kuma ta zama ruwan dare a aikace.A yawancin lokuta, da alama wutar lantarki ta isa a yi amfani da ita, amma asarar ba a ƙidaya ba.Sakamakon haka, kamara ba za ta iya aiki kullum ba saboda rashin isasshen wutar lantarki, kuma ba za a iya samun dalili koyaushe ba.
5. POE wutar lantarki juriya
Tabbas, abin da aka ambata a sama shine juriya na kebul na cibiyar sadarwa lokacin da nisan samar da wutar lantarki ya kai mita 100, wanda shine ikon da ake samu a mafi girman nisan samar da wutar lantarki, amma idan ainihin nisan samar da wutar lantarki yana da ɗan ƙaramin ƙarfi, kamar 10 kawai. mita, to, juriya ne kawai 2Ω, daidai da asarar mita 100 shine kawai 10% na asarar mita 100, don haka yana da matukar muhimmanci a yi la'akari da ainihin amfani lokacin zabar kayan aikin PSE.
Juriya na mita 100 na kebul na cibiyar sadarwa na kayan daban-daban na nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan nau'ikan murdade guda biyar sun jure wa juriya:
1. Ƙarfe mai suturar ƙarfe: 75-100Ω 2. Waya mai ɗorewa na aluminum: 24-28Ω 3. Waya mai launin azurfa: 15Ω
4. Kebul na cibiyar sadarwa na jan karfe mai suturar jan karfe: 42Ω 5. Kebul na cibiyar sadarwar jan ƙarfe mara iskar oxygen: 9.5Ω
Ana iya ganin cewa mafi kyawun kebul, mafi ƙarancin juriya.Bisa ga dabarar Q=I²Rt, wato, wutar da aka rasa yayin aikin samar da wutar lantarki ita ce mafi kankanta, don haka ya kamata a yi amfani da kebul da kyau.A zauna lafiya.
Kamar yadda muka ambata a sama, dabarar asarar wutar lantarki, Q=I²Rt, don samar da wutar lantarki ta poe ta sami mafi ƙarancin asara daga ƙarshen wutar lantarki ta PSE zuwa na'urar karɓar wutar lantarki ta PD, ana buƙatar mafi ƙarancin halin yanzu da ƙaramin juriya don cimma nasara. mafi kyawun sakamako a cikin dukkanin tsarin samar da wutar lantarki.
Lokacin aikawa: Maris 17-2022