Wide range watt hour meter. In recent years, due to the improvement of the living standards of residents, the number of household appliances installed is increasing, and the capacity is large, but the possibility of using them at the same time is small. If the old single range watt hour meter is selected, the rated current is too large. When the actual load is very small, the operating current may be less than 10% of the rated current of the watt hour meter, which may lead to inaccurate measurement; otherwise, if the rated current of the watt hour meter is too small, once the household appliances are used at the same time, the watt hour meter may be burnt out due to overload. The wide range watt hour meter can overcome the above problems. As long as the total current of the household appliances is within the rated current range of the watt hour meter, it can be measured safely and accurately. Therefore, the electric energy meters installed by residents in rural and urban power network transformation are generally long-life and wide range meters. Wide range watt hour meter is also called high overload multiple watt hour meter. Its overload capacity can reach 2-4 times. That is, the rated current of this kind of watt hour meter is not a fixed value, but an elastic range. If the nameplate of single-phase meter is marked with 2.0 grade, 220 V, 10 (40) a, the overload capacity of the meter is 4 times; when the rated current of the meter is within 10-40 a, the accuracy can still meet the requirements of level 2.0. However, the overload capacity of 2.0 class, 220 V, 10 a watt hour meter is only 1.5-2 times.
Mechanical electric energy meter with single electric energy measurement function is difficult to be competent for time-sharing measurement, load control, parameter preset, data acquisition, storage and real-time transmission and other functions at the same time.
Multi function watt hour meter. No matter what kind of electric energy meter, to complete the measurement of electric energy, it must have at least two functions: one is to generate the power signal consistent with the actual power; the other is to accumulate the power signal to obtain the electric energy value.