Now electricity meters are mainly divided into two categories, one is single-phase electricity meters, one is three-phase electricity meters, their functions and the scope of use are somewhat different. Electricity meter as an intelligent device terminal, has penetrated into all aspects of our life, so how to select and connect the electricity meter? What are the differences between three-phase and single-phase electricity meters?  What should be paid attention to in connection? 

I. What are the differences between a three-phase meter and a single-phase meter?   

1. Different functions   

Generally, single-phase meters intelligently measure active power or reverse active power, and their functions are relatively simple compared with three-phase meters. In addition to the active power metering, three-phase electricity meter can also measure reactive power, convenient function three-phase electricity meter is more complex than single-phase electricity meter.  

2. Different scope of application  

Three-phase meters are generally used in places with large current usage, such as factories, government buildings, villas, shops, etc., which have large demand for electricity. Therefore, three-phase electricity meter is the best choice. Three-phase electricity meter can also be used with transformer. Therefore, three-phase electricity meter with transformer has no maximum current. As long as the transformer ratio is enough, it is ok.   

Although single-phase electricity meter can also do mutual inductance, but single-phase electricity meter is mostly direct, as long as it is suitable for rental rooms, hotels and apartments, direct electricity meter,  

There is also a requirement for the maximum current, which will burn out the meter.

II. Wiring what matters needing attention?  

Whether it is three-phase mutual inductance meter or single-phase mutual inductance meter, the following points must be paid attention to when wiring:  

S1 must be connected to 1, S2 to 3, can not be connected inversely;  Otherwise there will be meter reversal;  

The live wire must enter from side P1 of the transformer and exit from side P2.  Otherwise there will be meter reversal; 

The state requires that wires connecting S1 and S2 must be more than 2.5 square copper wires;  

To prevent high voltage caused by open current transformers, current transformers S1 or S2 must be grounded, generally connected to the ground bar of the distribution box or connected to the ground.

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