The 3-pole Swiss plug and socket (J02-3) is a common electrical connection device widely used in Switzerland and some other countries. Compared with plugs and sockets in other countries, 3-pole Swiss plugs and sockets have significant features and differences in design, specifications and usage scenarios. These differences are explored in detail below.

1. Design and shape
Swiss plugs usually have a three-pole design, with two round prongs for phase and neutral and a third flat prong for ground. This design ensures the security and stability of the connection. In contrast, plugs in other countries such as the United States and the United Kingdom use flat or square prongs that vary in shape and configuration. For example, plugs in the United States usually only have two parallel prongs.

2. Rated voltage and current
The standard voltage rating of 3-pole Swiss plug sockets is 230V and the current rating is usually 10A or 16A. This is in contrast to many countries such as the United States (120V, 15A) and Japan (100V, 15A), which have significantly lower voltages than Switzerland. This difference will directly affect the design and safety of the equipment when using electrical appliances.

3. Pin design
The prongs of Swiss plug sockets are longer and rounded, which helps provide a larger contact area when inserted, ensuring a good electrical connection. The pin designs of other countries, such as the BS 1363 plugs used in British households, are usually shorter and square, with additional safety precautions, such as protection against electric shock.

4. Grounding method
Swiss plugs and sockets usually place the grounding prong between the two phase and neutral prongs. This design ensures that the plug is grounded first when plugged in, which increases the safety of use. In contrast, the British plug is connected to the ground wire at the last step of insertion, further reducing the risk of electric shock.

5. Safety standards
Different countries have different safety standards for plugs and sockets. Swiss plugs and sockets follow SEV (Swiss Electrotechnical Association) standards to ensure that their products meet high safety requirements. Other countries also have their own standards, such as UL (Underwriters Laboratories) certification in the United States and BS standards in the United Kingdom, to ensure the safety of electrical equipment during use.

6. Applicability
Due to differences in design and specifications, 3-pole Swiss plug sockets are usually not directly compatible with plugs from other countries. During international travel or cross-border use of electrical equipment, users need to use adapters or transformers to resolve mismatches in voltage and plug shape.