# 16 Difference Between Core Type and Shell Type Transformer | Circuit Diagram

In this article, I am describing the difference between core type and shell-type transformer.

In an earlier tutorial, we have studied the electrical transformer and its construction. Under construction and winding, transformer are classified into two types such as-

1. Core types of Transformer
2. Shell types of Transformer

Both core-type and shell-type transformers consist of different factors like construction, voltage rating, electric power (kVA) rating, cost, size, insulation stress, and many more things.

Let see each of those factors.

#### Difference Between Core type and Shell Type Transformer

These two transformer types are classified based on transformer construction.

The transformer can also be classified into different types based on measurement, cooling system, electrical power, and winding. Check the classification of the transformer for more detail.

In a tabular form, you can learn the topmost 16 different points for core type transformer vs shell type transformer.

 Sr. No. Content Core Type Transformer Shell Type Transformer 01 Magnetic Circuit In a core-type transformer, a single magnetic circuit occurs in a series form. In a shell-type transformer, the double magnetic circuit occurs in parallel form. 02 Magnetic Flux The magnetic fluxes flow in only one magnetic path. The magnetic fluxes flow in two different magnetic paths. 03 Construction In this transformer, windings surrounded by the Core. In this transformer, the core surrounded by windings. 04 Winding Types The concentric or cylindrical types of windings are used in core type transformers. The sandwich or disc types of winding are used in shell-type transformers. 05 Copper Winding (conducting material) It requires more copper for windings. It requires less copper for windings as compared to the core type transformer. 06 Applications (Voltage rating ) It is used for high voltage applications. Usually, it is used for low or medium voltage. 07 Cooling System Core type transformer can easily provide a natural cooling system (like Air) for winding. Shell-type transformer can’t easily provide the natural cooling system for winding. 08 Core Limb (or Legs) The core consists of two limbs in a single-phase transformer. The core consists of three limbs in a single-phase transformer. 09 Insulation It requires less amount of  insulation materials due to construction of LV and HV windings. It requires more amount of  insulation materials over the core type transformer. 10 Maintenance It requires less maintenance as compared to the shell-type transformer. It requires more maintenance. 11 Repair It is easy to repair. You can easily remove and replace the coil from the core. It is very difficult to repair. You can’t easily remove the coil from the core. 12 Power Output It gives low output power. It gives high output power. 13 Losses (Copper and Iron Losses) More losses occur in core types of transformer. Fewer losses occur in shell types of transformer. 14 Power Efficiency Core type transformer has a low power efficiency due to less output power and high leakage flux. Shell-type transformer has high power efficiency due to high output power and low leakage flux.

Note: Learn here different type of Transformer losses in detail

15. Lamination Design of Transformer

‘L’ shape lamination is used for core type transformer design.

‘E’ or ‘I’ shape lamination is used for shell type transformer design.

16. Circuit Diagram of Core Type and Shell Type Transformer

Circuit Diagram of Core Type Transformer

Circuit Diagram of Shell Type Transformer

I have covered 16 points in core type transformer vs shell type transformer.

Online Quiz to test your knowledge:

If you are ready to give the online quiz, you can directly join electrical Transformer Quiz.

If you have any queries related to the difference between core type and shell-type transformer, kindly share in the comment section.

Are you looking for job?

Job openings »

### 20 thoughts on “16 Difference Between Core Type and Shell Type Transformer | Circuit Diagram”

1. Superb

• Thanks, Niraj 🙂

2. Nice knowledge sharing , in case if you need any kind of help for the Transformer design or On site Transformer work knowledge sharing from my end please do let me know.

We as TEAM VERTO are working in four Verticals

Transformer design center & Third Party inspection upto 100MVA , 220kV all types of special and Power distribution Transformers.

Transformers erection, Installation and commissioning sevices, on site tests

Special Transformers manufacturing

Power factor improvement and Analysis etc..

[email protected]
[email protected]

• Thanks for your kind words. I find them truly motivating. Definitely, I will reach out to you if there is anything we can bring more value to our community. It’s great knowing about TEAM VERTO. Feel free to let me know if I can help you with anything. 🙂

3. Hello Dipali,

Really liked the content you shared about Transformers.

I would like to connect with you to know more about electrical power systems and Transformer.

4. Very nice Dipali.

5. Nice

6. core type

7. VERY NICE ARTICLE MADAM JI. MAI, JE SSC (JUNIER ENGINEER) KI TAIYARI KAR RAHA HU. AAP KA BLOG OR WEBSITE MERE LIYE HELPFUL HAI, IS SE LAGBHAG MUJHE SABHI ELECTRICAL JANKARIYAN PRAPT HO RAHA HAI.

ISKE LIYE AAPKO DIL SE DHANYAWAD.

• I’m really glad, Suraj. You find our blog very helpful to exam preparation.

All the best!

8. Thanks Didi for providing us knowledge about types of transfomer!

• You’re welcome, Devraj 🙂

I have some corrections.
1.In core type, the LV winding is nearer to core so the insulation level is low as compared to shell type where additional insulation between HV and core is required.
2. Due to low insulation level in core type , it is generally used for high voltage application

It can be added : cross sectional area of core type is less than shell type.
Rectify me if not correct.
Thanks.