What is leading pole tip and trailing pole tip?

( The pole tip which is first met during rotation of armature is known as leading pole tip and other as trailing pole tip ). The PQ represents main flux, PR represents armature flux and PS represents resultant flux as shown in the Figure C.

What is demagnetization and cross magnetization?

The opposition of armature flux on the main field flux is called armature reaction. This armature reaction has two undesirable effects, either it weakens (reduces) the main field flux called ‘Demagnetising Effect’ or it distorts the main field flux called ‘Cross-magnetising Effect’.

What is Demagnetising effect?

The term demagnetizing field reflects its tendency to act on the magnetization so as to reduce the total magnetic moment. It gives rise to shape anisotropy in ferromagnets with a single magnetic domain and to magnetic domains in larger ferromagnets. (See magnetic hysteresis.)

What is cross magnetization?

Cross-magnetisation is the behaviour of machine mag- netic materials in which the main driving magnetomotive force (MMF) is not applied in the geometrically favoured direction of the magnetic component, so that there is some magnetisation of the component across the favoured direction.

What is a trailing pole tip?

Definition of trailing pole tip : the edge of the pole piece of a dynamo or motor which the wires on the armature pass as they enter the gap.

What is Demagnetising effect of armature reaction?

In general, armature reaction distorts the main field distribution in the air gap periphery.It also leads to demagnetization effect in the machine. Demagnetization effects of armature mmf will reduce the total flux per pole. This reduction is about 1 to 5\% from no load to full load.

What is the meaning of cross magnetization?

Cross-magnetisation encompasses the magnetic behaviour of saturable machine materials when the vector of the main magnetomotive force (MMF) is applied in a direction that is not geometrically or analytically favoured in the magnetic structure of the machine.

Why demagnetization process is important?

Demagnetization is required to remove the magnetic fields in the material that counteract those of the eddy current probe. This interaction can influence the test so strongly that the test results exceed the sorting threshold and the test piece is declared as a bad part despite its sufficient properties.

What is demagnetization factor?

[dē′mag·nə‚tīz·iŋ ‚fak·tər] (electromagnetism) The ratio of the negative of the demagnetizing field to the magnetization of a sample. Also known as demagnetization coefficient.

How does demagnetization happen?

Demagnetization processes include heating past the Curie point, applying a strong magnetic field, applying alternating current, or hammering the metal. While demagnetization may occur by accident, it is often performed intentionally when metal parts become magnetized or in order to destroy magnetic-encoded data.

What does the word demagnetize mean?

magnetic properties
transitive verb. : to deprive of magnetic properties.