The starting current of the air conditioner is 6~7 times of the rated current.

Oxford Air Conditioning Repair Q&A: How to Coordinate the Electric Meter Capacity with Air Conditioners

The capacity of household electric meters is generally between 3~10A. In summer, many families add air conditioners with power ratings of 750~1500W (1~2P). The rated current for a 2P air conditioner is around 7.4A, and the starting current is 6~7 times the rated current, which means the starting current for a 2P air conditioner is approximately 40A. So, will this burn out the electricity meter? Let's analyze this from the structure of the electricity meter: the stator of an electricity meter usually consists of a voltage coil and a current coil. The voltage coil is connected in parallel with the current coil (220V), while the current coil is connected in series with the load. Under the action of the rotating magnetic field, the disc also rotates, and its speed is greater than or equal to the speed of the rotating magnetic field. Therefore, an electricity meter is essentially an asynchronous motor.

The larger the load current, the faster the meter runs. However, the speed of the electricity meter being proportional to the load has a certain range. When the current is too small, the electromagnetic torque is less than the friction force, so the meter does not move. When the current far exceeds the nominal value of the electricity meter, the meter spins very fast. But the speed of the rotating magnetic field is 3000 rpm, so the rotational speed of the electricity meter's disc cannot exceed 3000 rpm. This means that when the load current reaches a certain level, the reading on the electricity meter is no longer directly proportional to the load consumption, i.e., it is less than the actual energy consumption of the load. The current coil of the electricity meter is connected in series with the load, and the large current mainly impacts the current coil. Generally, the current coil is quite thick and can fully withstand the instantaneous starting impact current of more than 40A, so the possibility of burning out the electricity meter is very small.

In general, the rated current for air conditioners with power ratings of 750~1500W (1~2P) is between 3.4~7A. It is best to choose an electricity meter with a capacity of 10A. If the original installed electricity meter is 3(6)A, there is no need to replace the meter for air conditioners with power below 1.5P (1200W). The concern about the electricity meter being burned out is unnecessary.

Source of the article: http://blog.sina.com.cn/aokesikw