Misali Maximum Over-Current Protection (MOCP vs MCA vs FLA vs LRA)

فیلڈ: Karkashin Kuliya da Dukkana

China

Ma Maimaita MOCP a Tsarin Kuliya

Ma Maimaita MOCP a Tsarin Kuliya?

MOCP na nufin Maximum Over-Current Protection da aka bayyana cewa shi ne muhimmin yadda ake gano a kan abubuwa masu kuliya (kamar fuse ko circuit breaker) wanda ke shiga abubuwan da suka fi sani a kan kuliya (kamar motor ko air conditioner). MOCP shine muhimmin yadda ake gano a kan rating or size of the circuit breaker wanda zai iya haɗaƙar da hanyar aiki a tushen ba daidai.

Idan abubuwa masu haɗaƙar da suka fi sani suna fi kadan, za su iya bazu a tushen ba daidai, kuma za su iya haifar da wire ko abubuwa a kan kuliya saboda sautin jiki. Saboda haka, ya kamata a yi haɗaƙar daidai a kan abubuwa masu haɗaƙar da suka fi sani.

Yadda ake gano a kan MOCP ta tabbatar da muna iya samun muhimmin yadda ake gano a kan abubuwan masu haɗaƙar da suka fi sani kamar fuse ko circuit breaker. MOCP zai iya amfani da ita don haɗaƙar da wire ko abubuwan da suka fi sani a tushen ba daidai.

Saboda haka, MOCP ko MOP = Maximum Over-Current Protection = Maximum Fuse or Circuit Breaker Rating.

MCA vs MOCP vs FLA vs LRAs

Bayanin MCA, MOCP, FLA, da LRAs yana da muhimmanci saboda an buƙaci a kan wannan bayanin don haɗaƙar da wire da kuma haɗaƙar da abubuwan da suka fi sani. Ba ni a fada a kan abubuwan.

MCA

MCA na nufin Minimum Current Ampacity ko da Minimum Circuit Ampacity ce ita ce misalai karamin kwayoyi na karshe don kashi kable ko da sashi a cikin wasu karshe. Haka, MCA ce misalai karamin kwayoyi na karshe da kable ko sashi su yana iya kawo da shiga tsari a kan harkokin adadin.

Misalai karamin kwayoyi na karshe ce karamin kwayoyi da sashi su yana iya kawo da shiga tsari, saboda haka, yana da zama karamin kwayoyi na sashi ko kable.

Rahotanni MCA tana taimakawa wajen samun adadin kable na musamman don hasashen ya ba a yi karfin kashi a kan harkokin adadin.

Saboda haka, MCA = Minimum Current Ampacity = Adadin Kable ko Sashi Na Musamman

Rahotanni MCA ce 1.25 daga FLA na motor tare da duk abubuwa masu karfi kamar karamin kwayoyi na heater.

MCA = 1.25 * (Motor FLA + Heater Current)

MOCP

MOCP ce rahotanni da ake amfani da shi wajen samun adadin mafi yawan abubuwan da ake amfani da su don kawo kashi a kan karshe, kamar circuit breaker ko fuse, don kawo kashi a kan kable da abubuwa a kan harkokin adadin.

Adadin circuit breaker ko fuse ya kamata yake da muhimmanci da rahotanni minimum current amps (MCA). Saboda haka, rahotanni MOCP yana da darajar da yake da muhimmanci da rahotanni MCA.

MCA da MOCP suna da muhimmanci a kan samun adadin kable/sashi na musamman da kuma adadin mafi yawan fuse/circuit breaker da aka tabbatar da shi don kawo kashi a kan harkokin adadin, kuma don kawo kashi a kan hadin kashi.

Rahotanni MOCP ce 2.55 daga FLA na motor na mafi yawa tare da duk abubuwa masu karfi da karamin kwayoyi na 1 A ko da yake da za a yi karfa a kan lokacin.

MOCP = (2.25 * FLA na Motor na Mafi Yawa) + (Duk Abubuwan Motor) + (Duk Abubuwan Masu Karfi kamar Karamin Kwayoyi na Heater)

FLA

FLA yana nufin Full Load Ampere wanda shi ne kashi da tushen kayan aiki ko machines za su iya haɗa a cikin yanayin hanyar masu gaba mai tsawo. FLA yana nuna kashi na full load a kan rated voltage da load don bayar output HP ta rated.

Ma'anarta FLA ya fi yawa saboda anam amfani da ita don samun ma'anarta MCA da MOCP. Saboda haka, kuma ya fi yawa don samun ci gaba na conductors, Equipment, overcurrent protection devices kamar fuse, MCB, circuit breaker, etc.

$\begin{align*} FLA = 0.80 * MCA \end{align*}$

$\begin{align*} FLA = 0.44 * MOCP \end{align*}$

LRA

LRA yana nufin Locked Rotor Ampere wanda shi ne kashi da motori za su iya haɗa a cikin yanayin locked rotor. Ma'anarta LRA zai iya kasance da starting current ta motori da kuma about 8 times the full load current.

$\begin{align*} LRA = 8 * FLA \end{align*}$

Yadda LRA tana amfani da shi don kula da yawan hanyar gajarta na fadada mawakin motoci. Idan hanyar gajarta yana da zama 80% zuwa 85%, motoci zai iya baki da ya fara kuma yana fara haɗa.

Yadda a Kula da MOCP

Yadda MOCP tana ba da shi a nameplate wanda mutummai ta bayarwa don inganta hankali. Wasu wurare masu inganta hankali kamar fuse da circuit breaker suna kunna cewa suka daidai kafin abin da adadin amfani da shi yana da zama mafi yawan MOCP. Zan iya kula da yawan MOCP based on FLA.

MOCP = (2.25 * FLA na Mawaki na Mafi Yawa) + (Wasu Abubuwan Mawaki) + (Duk wasu abubuwan amfani da shi mai yawa kamar heater load)

Yadda da take da tsari na amfani da shi a circuit breaker shine 15 A, 20 A, 25 A, 30 A, 35 A ……, 60 A, etc. inda 15 A shine mafi yawan amfani da shi a fuse ko circuit breaker wanda National Electrical Code a USA ta samun sahihi.

Akwai nau'o'i biyu na amfani da shi a wurare masu hanyar gajarta mai yawa.

Nau'o'i Inductive Load i.e., Motor, Compressor, etc.…
Nau'o'i Resistive Load i.e., Electric Heaters.

Yadda a Kula da MOCP

Karkashin, aiki don kula da FLA na Mawaki ko Compressor – Wannan shine Full load Current a hanyar gajarta da amfani da shi.

Karkashin, aiki don kula da heater load – Wannan shine amfani da shi mai yawa.

Ba da kula da ma'ana ta MOCP, zan iya zaɓe ma'ana ta MOCP da suka dacewa da abubuwa uku da suka bayar.

Idan MOCP $\neq$ Tafada na 5 yani, idan ma'ana da aka kula da shi ba shi tafada na 5 ba, wanda ya kula da shi zai zama da takwas zuwa cikin ma'ana na fadada mai sauƙi ko mai ɗaukan saukar.
Idan MOCP < MCA yani, idan ma'ana da aka kula da shi ya fi ɗaya da ma'ana ta MCA, wanda ya kula da shi zai zama da MCA kuma zai zama da takwas zuwa cikin ma'ana na fadada mai sauƙi ko mai ɗaukan saukar, yawancin da suka dacewa da tafada na 5. Saboda haka, ma'ana ta MOCP ba zai fi ɗaya da ma'ana ta MCA ba.
Idan MOCP < 15 A yani, idan ma'ana da aka kula da shi ya fi ɗaya da 15 A, wanda ya kula da shi zai zama da takwas zuwa 15 A. Wannan 15 A shine ma'ana mafi ɗaya na sauƙi ko mai ɗaukan saukar da aka tabbatar da shi a cikin ƙasa.

Ina bukata misalai na yadda a zaɓe ma'ana ta MOCP da suka dacewa da abubuwan uku da suka bayar.

Misali 1 : Kula da ma'ana ta MOCP da suka dacewa da muhimmiyar sauki 3 – phase, 480 V, 10 KW da motor FLA 4.5 A.

Bayanai da aka bayar: Sauran Kirki = 3-phase 480 V, Muhimmiyar sauki = 10 KW, Motor FLA = 4.5 A

$\begin{align*} \begin{split} for \,\, 3-phase \,\, load \,\, the \,\, current \,\,I = \frac {P}{\sqrt3 * V} \\ Heater\,\,current \,\, (I) = \frac {10000}{\sqrt3 * 480} \\ = \frac {10000}{1.73 * 480} \\ Heater\,\,current \,\, (I) = 12.04 \,\,A \end{split} \end{align*}$

Na gode,

$\begin{align*} MCA = 1.25 * (Motor\,\,FLA + Heater\,\,Current) \end{align*}$

$\begin{align*} = 1.25 * (4.5 + 12.04) \end{align*}$

$\begin{align*} = 1.25*16.54 \end{align*}$

$\begin{align*} MCA = 20.68 \,\, A \end{align*}$

kuma

$\begin{align*} MOCP = (2.25 * FLA\,\,of\,\,the\,\,Largest\,\,Motor)+(Other\,\,Motor\,\,Loads)+ \\(All\,\,Heater\,\,Load) \end{align*}$

$\begin{align*} = (2.25 * 4.5) + (0) + (12.04) \end{align*}$

$\begin{align*} = 10.125 + 12.04 \end{align*}$

$\begin{align*} MOCP = 22.17 \,\, A \end{align*}$

Hakan, yadda MOCP ba tana da dama mafi girma ɗaya zuwa 5 kuma an zama shi zuwa gaba mai karfi na ɗaya, ya nufin 20 A. saboda haka,

MOCP = 20 A (sharta 1),

Amma 20 A yana da kyau da hukuma MCA, kuma haka, MOCP ta ce da MCA, sannan an gaba shi zuwa ingancin tashar circuit breaker. Saboda haka, MOCP ita ce 25 A wajen wannan 3-phase load (Hukuma 2).

(Kara a USA 277 V ita ce 1 – phase voltage da 480 V ita ce 3 – phase voltage, kuma a India 230 V ita ce 1-phase da 415 V ita ce 3-phase voltage).

Misalai 2: Karkashin MOCP value wajen 1 – phase, 277 V, 5 KW heater load.

Bayanan Da aka Bani: Supply Voltage = 1-phase 277 V, Heater load = 5 KW, Motor FLA = 0

$\begin{align*} \begin{split} for \,\, 1-phase \,\, load \,\, the \,\, current \,\,I = \frac {P}{V} \\ Heater\,\,current \,\, (I) = \frac {5000}{277} \\ Heater\,\,current \,\, (I) = 18.05 \,\,A \end{split} \end{align*}$

Daga baya,

$\begin{align*} MCA = 1.25 * (Motor\,\,FLA + Heater\,\,Current) \end{align*}$

$\begin{align*} = 1.25 * (0 + 18.05) \end{align*}$

$\begin{align*} = 1.25 * 18.05 \end{align*}$

$\begin{align*} MCA = 22.56 \,\, A \end{align*}$

$\begin{align*} MOCP = (2.25 * FLA\,\,of\,\,the\,\,Largest\,\,Motor)+(Other\,\,Motor\,\,Loads)+ \\(All\,\,Heater\,\,Load) \end{align*}$

$\begin{align*} = (2.25 * 0) + (0) + (18.05) \end{align*}$

$\begin{align*} MOCP = 18.05 \,\, A \end{align*}$

Hakan, MOCP < MCA, kuma uku da dukkan MOCP ya kasance da MCA kuma an yi tsaftaci zuwa masu takarda mafi yawan circuit breaker. Saboda haka, MOCP ya kasance 25 A wajen fadada 1-phase heater load (Condition 2).

Misalai 3: Karkashin cikakken tasirin MOCP wajen fadada 3 – phase, 480 V, 5 KW heater load.

Bayanin da aka bayar: Supply Voltage = 3-phase 480 V, Heater load = 5 KW, Motor FLA = 0

$\begin{align*} \begin{split} for \,\, 3-phase \,\, load \,\, the \,\, current \,\,I = \frac {P}{\sqrt3 * V} \\ Heater\,\,current \,\, (I) = \frac {5000}{\sqrt3 * 480} \\ = \frac {5000}{1.73 * 480} \\ Heater\,\,current \,\, (I) = 6.02 \,\,A \end{split} \end{align*}$

Daga nan,

$\begin{align*} MCA = 1.25 * (Motor\,\,FLA + Heater\,\,Current) \end{align*}$

$\begin{align*} = 1.25 * (0 + 6.02) \end{align*}$

$\begin{align*} = 1.25 * 6.02 \end{align*}$

$\begin{align*} MCA = 7.53 \,\, A \end{align*}$

kuma

$\begin{align*} MOCP = (2.25 * FLA\,\,of\,\,the\,\,Largest\,\,Motor)+(Other\,\,Motor\,\,Loads)+ \\(All\,\,Heater\,\,Load) \end{align*}$

$\begin{align*} = (2.25 * 0) + (0) + (6.02) \end{align*}$

$\begin{align*} MOCP = 6.02 \,\, A \end{align*}$

A cikin wannan, MOCP < 15 A kuma haka, yadda MOCP ta shafi ta zama 15 A wanda shi ne muhimmanci na tsari da ke tattara waɗannan (Sharti 3).

Yadda Ka Kula MCA

Yadda MCA ta faruwa ta bayar da ma'a nameplate kan gida ko unit da take da shi mai sarrafa don haɗaƙi aiki. Zan iya kula yadda MCA ta faruwa ta da kula yadda FLA ta faruwa ta.

Don kula yadda MCA ta faruwa ta, ya kamata ka kula tsari na current da duka wasu gida kamar fan, motor, compressors, etc….

MCA = 1.25 * (Motor FLA + Heater Current)

A baka wani misali na tattalin karamin yadda ake karkasho ma'aikatar MCA.

Misali: Karkasha ma'aikatar MOCP na jiki 3 - phase, 480 V, 12 KW da yanayi FLA 5 A.

Bayanai da aka bayar: Kirkiyar shirya = 3-phase 480 V, Yanayi = 12 KW, Motor FLA = 5 A

$\begin{align*} \begin{split} for \,\, 3-phase \,\, load \,\, the \,\, current \,\,I = \frac {P}{\sqrt3 * V} \\ Heater\,\,current \,\, (I) = \frac {12000}{\sqrt3 * 480} \\ = \frac {12000}{1.73 * 480} \\ Heater\,\,current \,\, (I) = 14.45 \,\,A \end{split} \end{align*}$

Tana,

$\begin{align*} MCA = 1.25 * (Motor\,\,FLA + Heater\,\,Current) \end{align*}$

$\begin{align*} = 1.25 * (5 + 14.45) \end{align*}$

$\begin{align*} = 1.25 * 19.45 \end{align*}$

$\begin{align*} MCA = 20.7 \,\, A \end{align*}$

Saboda haka, balancin MCA shine 20.7 A.

Kamar yadda aka magana a nan, balancin MOCP da MCA suna bani a nameplate na zabur. Wannan ana nuna a nameplate ta hagu.

Kamar yadda aka nuna a nameplate, yawan kadan ko rating daga fuse ko circuit breaker shine 20 A, wanda ya ce cewa balancin MOCP shine 20 A. Saboda haka, za a iya zaba aikin da ke taimakawa wa overcurrent protection don haka.

Duk da haka, Minimum circuit ampere shine 12.2 A, wanda ya ce cewa balancin MCA shine 12.2 A. Saboda haka, za a iya zaba yawan kadan wire na musamman don haka.

Balancin LRA da FLA na motor fan suka bani a nan.

Bayanin: Gaskiya ta fitarwa, babban ra'ayi sune za'a shirya, idani babu gaskiya zai iya shiga adadin shugaban.

Ba da kyau kuma kara mai rubutu!

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