The choice between a 3P+N or a 4P PD depends on your specific application needs, the type of power supply to your system (3-phase 3-wire or 3-phase 4-wire), and the level of protection you wish to achieve. Here are the basic differences and application scenarios of these two types of leakage protectors to help you make your choice:
Structure: The 3P+N leakage protector has three phase protection and one neutral protection, but the neutral (N) is usually not open protection.
Applications: It is suitable for three-phase four-wire power system, especially when the neutral line does not need to be disconnected or the neutral line load is small.
Features:: In some cases, maintaining the continuity of the neutral is very important for the proper functioning of the system, and 3P+N offers this possibility.
StructureThe 4P leakage protector has three phases and one neutral protection, and the neutral (N) is also disconnected and can cut off all phases and neutrals at the same time when leakage is detected.
Applications: It is suitable for three-phase four-wire power systems, especially when the neutral wire needs to be completely disconnected, such as when the neutral wire may carry a large load or the system design requires that the neutral wire must also be disconnected in the event of leakage.
Features:: Provides comprehensive protection to ensure that in the event of a leakage, the power supply can be completely cut off, including all phases and neutrals, for increased safety.
Security: From a safety point of view, the 4P leakage protector provides more comprehensive protection because it is able to disconnect all phase and neutral wires at the same time in the event of leakage.
Applicability: Which type of leakage protector you choose depends on your specific power system and security needs. If you have a system where the neutral does not need to be disconnected under normal or fault conditions, or if the system design allows the neutral to remain continuous during leakage protection operation, then 3P+N may be a suitable choice. On the contrary, if you need to completely disconnect the neutral wire in any case of leakage, then a 4P leakage protector will be a better choice.
When choosing a leakage protector, it is important to consider the specific requirements and safety standards of your power system. In some specific applications, the handling of neutral wires may be clearly defined, which should be the main basis for your choice of leakage protector type.