Key Differences between Core Type and Shell Type Transformer

1. In core type transformer the core surrounds the windings whereas in shell type transformer the winding surrounds the core of the transformer.

2. In core type transformer the lamination is cut in the form of L-shape whereas, in shell type transformer, the laminations are cut in the E and L shapes.

3. The cross-section area of the core type transformer is rectangular, whereas the cross-section area of the shell type transformer is square, cruciform two slipped, or three stepped in shapes.

4. The core type transformer requires more copper conductor as compared to shell type transformer because in core type transformer the winding is placed on the separate limbs or legs.

5. The core type transformer is also called cylindrical or core winding transformer because their windings are arranged as the concentric coil. In shell type transformer, the low voltage winding and the high voltage winding are put in the form of the sandwich, and hence it is called the sandwich or disc winding transformer.

6. The core type transformer has two limbs, whereas the shell type transformer has three limbs. Flux Primary Windingㅇㅇ - Secondary Winding Shell Type Transformer Circuit Globe

7. The mechanical strength of the core type transformer is low as compared to shell type transformer because the shell type transformer has bracings.

8. The core type transformer required less insulation as compared to shell type transformer because shell type transformer has three limbs.

9. In core type transformer the flux is equally distributed to the side limb of the transformer whereas, in shell type transformer, the central limb carries the whole of the flux and the side limbs carry the half of the flux.

10. In core type transformer both the primary and the secondary windings are placed on the side limbs whereas, in shell type transformer, the windings are placed on the central limbs of the transformer.

11. The core type transformer has two magnetic circuits whereas the shell type transformer has one magnetic circuit.

12. The losses in a core type transformer are more as compared to shell type transformer because the core type transformer consists two magnetic circuits.

13. In core type transformer few windings are removed for maintenance. In shell type transformer numbers of the winding are required to remove for the maintenance.

14. The output of the core type transformer is less because it has more losses as compared to the shell-type transformer.

15. The winding of the shell type transformer is distributed type, and hence heat is dissipated naturally, whereas, in core type transformer, the natural cooling is not possible.