Answer / asif khan

Harmonic is presence of unwanted frequencies.
Few types of harmonics are listed below. these frequencies mainly gets generated due to modern electronic equipment e.g
Computer, inverters etc.

3rd level harmonics
5th level harmonic
7th Level Harmonic
11th level harmonics
13th level harmonics

3rd level harmonic is normal, however when it goes up to 5th or 7th it's considered a problem.
11th and 13th level harmonics usually found where rectifiers and DC loads are connected.

Answer / nilesh chougale

harmonics is nothing but an unwanted noise or ripples.

There are odd and even harmonics

Answer / kabilan

Harmonic is unwanted frequencies (AC)

Answer / s k tiwari

Harmonics just like air pollution in the air. its occurs due to inductive load

Answer / msr

presence of unwanted frequency component in current or
voltage other than fundamental frequency is known as harmonics .
basically harmonics are ac and dc harmonics .
we can also classified them as -
1.even harmonics (2nd ,4th,6th )frequency component
2.odd harmonics (3,5,7)
generally lower harmonics are more dangerous than higher
order harmonics.

Answer / harshit shukla

-harmonics are unwanted frequencies which distort current and
voltage wave forms and also increase I2R losses in line.
-In transmission line harmonics are produced due to transient
effect.They are also produced during switching ON and OFF of
transformer(magnetic coupling device)
-It is also noticed that in line when current peak and
harmonic peak occur at the same time,I2R loss become maximun.
-harmonics can be reduced by mounting filters near
transformers or generators.
-In power electronics devices it causes fluctuation.

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