Among the non-metallic materials of single-phase meter box, fiber-reinforced polyester material has very good anti-aging performance. The anti-aging performance test shows that the surface aging thickness is 20 years and less than 50 μ m。 The thickness of most boxes is 5 mm, less than 1% of the box thickness, so there is no obvious impact on the mechanical properties of the box. Foreign companies have adopted a special UV resistant surface treatment process to further strengthen its aging resistance. Its access method can be divided into two categories, one is direct access method, the other is transformer access method.

1. Direct access method:

If the load power is within the allowable range of the watt hour meter, that is, the current flowing through the current coil of the watt hour meter will not cause the coil to burn, then the direct connection method can be used.

2. Connection method through transformer:

When single-phase watt hour meter is used to measure the power consumption of single-phase circuit with large current, current transformer shall be used for current transformation, and the current transformer shall be connected to the current coil of the watt hour meter.