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Question
why there is a humming noise in transformer
 Question Submitted By :: Electrical-Engineering
I also faced this Question!!     Answer Posted By  
 
Answer
# 1
Basically, we used ferromagentic material in core...when
magnetic flux linked with thid core..thier is some
physically expand and contract slightly with each cycle of
the magnetic field...and that effect known as
magnetostriction..(Magnetostriction is a property of
ferromagnetic materials that causes them to change their
shape or dimensions during the process of magnetization...
it was first identified in 1842 by James Joule when
observing a sample of nickel)...due to this effect causes
fluctuating forces between the primary and secondary
windings. These incite vibrations within nearby metalwork,
adding to the humming noise, and consuming a small amount
of power.
 
Is This Answer Correct ?    19 Yes 1 No
Nilkanth Tailor
 
Answer
# 2
coz of eddy currents flowing in the core , and leakage
currents from leakage inductance to ground
 
Is This Answer Correct ?    6 Yes 4 No
Yasir Wani
 
 
 
Answer
# 3
the ansr given by mr.nilkanth is only the right ansr.
gud wrk pal.
 
Is This Answer Correct ?    1 Yes 1 No
Srikrishna
 
Answer
# 4
it is cause due to losses in winding 
Is This Answer Correct ?    0 Yes 1 No
Neeraj
 
Answer
# 5
Nilkanth Tailor's answer is correct 
Is This Answer Correct ?    0 Yes 1 No
Nishant2110
 
Answer
# 6
Nilkanth Tailor's answer is 100 % correct. Gudwork Nilkanth. continue your sharing which give us confidence in Transformer Field 
Is This Answer Correct ?    0 Yes 1 No
Hardip Dodiya
 
Answer
# 7
the reason of this type of noise is due to harmonics
genrated in transformer.
 
Is This Answer Correct ?    0 Yes 4 No
Hemant Kumar
 
Answer
# 8
i think it is due to mechanical fault which arose while
manufacturing the transformer
due to the small gaps in the core
 
Is This Answer Correct ?    3 Yes 16 No
Ghanshyam Singh
 

 
 
 
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