In DC generators lamination core are generally made of?

1 Answer

Answer :

In DC generators lamination core are generally made of silicon steel.

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Last Answer : For the parallel operation of two or more D.C. compound generators, we should ensure that series fields of all generators should be either on positive side or negative side of the armature.

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Last Answer : D.C. generators are normally designed for maximum efficiency around full-load.

Last Answer : The armature core of a D.C. generator is usually made of silicon steel.

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Last Answer : The desirable properties of transformer core material are high permeability and low hysteresis loss.

Last Answer : The transformer laminations are insulated from each other by thin coat of varnish.

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Description : A 40 kVA transformer has a core loss of 400 W and a full load copper loss of 800 W. The proportion of full load at maximum efficiency is

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Description : A single core lead sheathed cable with two dielectrics of permittivity 4 and 3, respectively, are subjected to same maximum stress. If the conductor diameter is 1.5 cm, the outer diameter of the first dielectric is (A) 1.125 cm (B) 1.5 cm (C ) 2 cm (D) 8 cm

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Description : A single core cable is designed to work for a single phase system with a peak voltage of 220 kV. The maximum permissible stress in the dielectric is not to exceed 20 kV/mm. For economical size, the overall core diameter of the cable is (A) 28.2 mm (B) 26.4 mm (C) 24.4 mm (D) 22.0 mm

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Description : A ferrite core has less eddy current loss than an iron core because?

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Last Answer : Material used for construction of transformer core is usually silicon steel.

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