Ohmmeter: Yadda Ya Kammala? (Series, Multi-Range & Shunt Type Ohm Meters)
Misali ya Ohmmeter?
An ohmmeter (ko kuma ake fi sani da ohm meter) shine wata aiki mai hakuri na sakamakon shirya na abubuwa (sakamakon shirya shine wata muhimmanci na shirya). Micro-ohmmeters (micro ohmmeter ko microhmmeter) da Milliohmmeters suna haɗa sakamakon shirya masu yawan, amma Megohmmeters (wata aiki mai hakuri ta Megger) suna haɗa sakamakon shirya masu miyali.
Duk wata aiki na sakamakon shirya. Yana iya zama mafi yawa ko kadan, amma yana zama mafi yawa tare da hawa don conductors da kuma yana ci gaba tare da hawa don semiconductors.
Akawo ake cika da ohmmeters. Tafin da suka fi dace a kan ohm meters shine:
Series ohmmeter.
Shunt ohmmeter.
Multi-range ohmmeter.
Tsarin Aiki na Ohmmeter
An fada aikin da battery, adjustable resistor, da kuma instrument mai bayarwa. An fada sakamakon shirya a terminal ob. Idan an fada circuit da sakamakon shirya, za a haɗa shirya kuma za a haɗa bayarwa.
Idan sakamakon shirya yana iya zama mafi yawa, za a haɗa shirya a cikin circuit ita yawan kada, kuma bayarwar instrument za a yi amincewa a tsari. Idan sakamakon shirya yana iya zama zero, bayarwar instrument za a yi a tsari zero.
D’Arsonval Movement
Wannan type na movement ana amfani da shi a DC measuring instruments. Tsarin aiki na wannan type na instrument shine idan an fada coil mai shirya a magnetic field, za a haɗa force, kuma wannan force za a haɗa pointer da ya yi bayarwa a instrument.
Wannan type na instrument tana da permanent magnet da kuma coil mai shirya. Coil yana iya zama rectangular ko circular. Iron core ana amfani da shi don ba flux da low reluctance, kuma yana ba high-intensity magnetic field.
Saboda high-intensity magnetic fields, torque mai haɗa ya zama mafi yawa, kuma sensitivity na meter ya zama mafi yawa. Shirya ta fito ne a biyu control springs, batun a faduwa da batun a kasa.
Idan direction na shirya an yi baka, direction na torque za a yi baka, saboda haka wannan type na instrument ana amfani da shi a DC measurements kawai. Torque mai haɗa tana da kyau da angle mai haɗa, kuma saboda haka wannan type na instrument tana da linear scale.
Don kunshi deflection na pointer, yawanci ake amfani da damping, wanda yana ba force da kyau da opposite a cikin deflecting torque, kuma saboda haka pointer ya zama a matsayin balagin value. Indication na breeding tana bayarwa a mirror, inda beam of light ya faru zuwa scale, kuma deflection ya zama mafi yawan bayarwa.
Akawo na advantages da ke amfani da D’Arsonval type instrument. Su ne-
Su na uniform scale.
Effective eddy current damping.
Low power consumption.
No hysteresis loss.
Ba su sa shiga stray fields.
Saboda suka samu advantages masu yawa, ake amfani da wannan type na instrument. Amma, akwai drawbacks kamar:
Ba zan iya amfani da shi a alternating current systems (DC current kawai)
Costlier compared to MI instruments.
Yana iya kasance error saboda aging na springs, kuma ba zan iya samun results masu accuracy.
Amma a halin resistance measurement, ake yi DC measurement saboda advantages da PMMC instruments suka ba su, kuma ake yi multiplication na resistance da 1.6 don samun AC resistance, kuma saboda haka ake amfani da wannan type na instrument saboda advantages. Disadvantages da suka ba su suna dole ne don advantages, kuma ake amfani da shi.
Series type Ohmmeter
Series type ohmmeter tana da current limiting resistor R1, Zero adjusting resistor R2, EMF source E, Internal resistance of D’Arsonval movement Rm and the resistance to be measured R.
Idan babu resistance da za a yi hakuri, shirya ta fito ne a cikin circuit ita yawan kada, kuma meter ya zama a tsari.
Akwai adjustment na R2 don meter ya zama a full-scale current value, saboda resistance ya zama zero a lokacin. Pointer indication ya zama zero. Idan AB ta yi open, za a haɗa high resistance, kuma za a haɗa shirya yawan kada. A lokacin, pointer deflection ya zama zero, kuma ya zama a tsari mafi yawa don resistance measurement.
Saboda haka, resistance between zeros to a very high value ya zama marked, kuma za a iya haɗa. Saboda haka, idan resistance da za a yi hakuri, shirya value ya zama yawan kada, kuma deflection ya zama recorded, kuma resistance ya zama measured.
Wannan method ya zama good, amma akwai limitations kamar decrease in the potential of the battery with its use, saboda haka adjustment must be made for every use. Meter ba zan iya read zero when terminals are shorted, kuma problems kamar haka zai faru, kuma ake counteract by the adjustable resistance connected in series with the battery.
Shunt Type Ohmmeter
