Maimaitar Zuba da Kuka (PMMC)

Muhimmiya Da Karamin Magana Da Maimakon Daji Da Turanci (PMMC)

Muhimmiya da karamin magana da maimakon daji da turanci (PMMC) – wanda ake kira D’Arsonval meter ko galvanometer – yana daya da kake iya bincike karamin magana ta tsakiyar maimakon daji tare da tabbatar da darajar da tsakiya ya yi a cikin magnetic field.

Muhimmin PMMC na iya kawo tsakiyar maimakon daji (ya'ni conductor) a bayanar da duwatsuwa masu sauki don in gina magnetic field mai zama. A cikin Faraday’s Laws of electromagnetic induction, conductor da ke da karamin magana a cikin magnetic field za su iya samun fadada a hagu da Fleming’s left hand rule.

Kadan (kyau) wannan fadada za ta mutane da karamin magana ta tsakiya. Pointer ta kashe a kan karni na tsakiya kuma an juye shi a kan scale.

Idan torques sun fi wasu, za ta tsakiya ya zama, kuma darajarsu a yanka za su iya bincika a kan scale. Idan magnetic field ta duwatsuwa ya zama uniform da spring linear, pointer deflection ta zama linear. Saboda haka za mu iya amfani da wannan dalilan lineari don in tabbatar da adadin karamin magana da ke doke a kan tsakiya.

Muhimminta PMMC (ya'ni D’Arsonval meters) ana amfani da su ne a bincike Direct Current (DC) karamin magana. Idan ake amfani da Alternating Current (AC) karamin magana, yanayin karamin magana za ta yara a nan half cycle, saboda haka, yanayin fadada za ta yara. Wannan ya haɗa da kyau na zero torque – saboda haka ba za a haɗa da noma game da scale.

Saboda haka, muhimmina PMMC sun iya bincike DC karamin magana da ƙwarewa.

Binciken Muhimmina PMMC

Muhimmin PMMC (ko D’Arsonval meters) ana gina da 5 abubuwa masu muhimmanci:

• Babban Babbar Duwatsuwa Ko System Da Duwatsuwa
  

• Tsakiyar Maimakon Daji Da Turanci
  

• System Da Kontrola
  

• System Da Damfa
  

• Meter
  

Babban Babbar Duwatsuwa Ko System Da Duwatsuwa

A yanzu anam amfani da duwatsuwa masu inganci, masu coercive force masu ƙwarewa saboda halin U shaped permanent magnet da soft iron pole pieces. Duwatsuwa da ake amfani a yanzu suna da alcomax da alnico wadanda suke ba da magnetic field masu ƙwarewa.

Tsakiyar Maimakon Daji Da Turanci

Tsakiyar maimakon daji na iya yi ƙungiyoyi a kan duwatsuwa masu sauki kamar yadda ake nuna a figure. Tsakiya an gine da many turns of copper wire kuma an juye shi a kan rectangular aluminium wanda ya kashe a jeweled bearings.

System Da Kontrola

Spring na iya taimakawa a kontrola muhimmina PMMC. Spring na iya taimakawa waɗanda suna da muhimmanci a gina path don in kawo karamin magana zuwa da ɗaya daga tsakiya.

System Da Damfa

Torque na iya samun damfan da movement of aluminium former a magnetic field da ake gina a kan duwatsuwa masu sauki.

Meter

Meter da muhimmina suna da pointer mai kyau don in iya yi ƙungiyoyi da scale wanda ya zama linear ko uniform da take yawan angle.

Equation Da Torque Na PMMC

Za a rubuta equation general don torque a cikin muhimmina PMMC. Ana sani cewa a cikin moving coil instruments deflecting torque na iya samun wannan expression:

• Td = NBldI inda N shine number of turns,

• B shine magnetic flux density a cikin air gap,

• l shine length of moving coil,

• d shine width of the moving coil,

• I shine electric current.

Idan a cikin moving coil instrument, deflecting torque ya kamata ita proportional to current, mathematically za a iya rubuta Td = GI. Saboda haka a cikin comparison G = NBIdl. A lokacin da ya zama steady state, controlling da deflecting torques suna fi wasu. Tc shine controlling torque, idan ake haɗa controlling torque da deflection torque

GI = K.x inda x shine deflection saboda haka current na iya samun

Saboda deflection ya kamata ita proportional to the current, saboda haka muna buƙaci scale uniform a kan meter don bincike current.

A nan za a hada a cikin basic circuit diagram na ammeter. Za a duba circuit kamar yadda ake nuna:

Current I an nuna wanda ya zama two components a point A. Two components suna da Is da Im. Idan na ƙarfin bayani game da magnitude values of these currents, za a duba construction of shunt resistance. Basic properties of shunt resistance suna nuna a cikin:

Electrical resistance of these shunts ba zai ɗauka a higher temperature, saboda haka suna da very low value of temperature coefficient. Also the resistance ba zai ɗauka a lokacin, last and the most important property they should posses is that they should be able to carry high value of current without much rise in temperature. Usually manganin na amfani a making DC resistance. Saboda haka muna iya cewa value of Is much greater than the value of Im as resistance of shunt is low. From the we have,

Inda, Rs shine resistance of shunt and Rm shine electrical resistance of the coil.