After running for a period of time, the reasons for the air conditioner's circuit breaker frequently tripping include an undersized power cord, aged or faulty circuit breaker, and substandard wiring. Based on my work experience, I will share my understanding of these issues.
According to your description, the air conditioner has a power rating of 4500 watts and is equipped with a 32A circuit breaker, which suggests that the power consumption of the air conditioner in your home is definitely more than 4500 watts. The reasons are as follows:
An air conditioner with a power rating of 4500 watts is commonly referred to as a 6P air conditioner, which is essentially a central air conditioning system with 4-5 indoor units.
Based on the formula P=cos∮UI, where P is the power of the air conditioner (4500 watts), U is the voltage (220V), and I is the current, the rated current is approximately 21A. Theoretically, a 25A circuit breaker would suffice. However, the 32A circuit breaker may have been chosen to accommodate the electrical auxiliary heating of each indoor unit. Based on experience, the power consumption of the electrical auxiliary heating is averagely 1200 watts per unit, totaling 6000 watts for 5 indoor units. However, it is unlikely that all indoor units will be operated simultaneously; most likely, only 2 units will be used at the same time. Therefore, calculating with a power of 2500 watts, the total rated power consumption becomes 7000 watts, and the rated current is approximately 32A, justifying the use of a 32A circuit breaker.
The air conditioner's wiring is configured with 4mm² copper core cables, which are commonly used as power cords in households. How much current can a 4mm² copper core cable carry? Based on experience, a 1mm² BV copper core cable can carry 6A of current, so the limit for a 4mm² cable is a current value of 24A.
As mentioned earlier, the main air conditioner has a power of 4500 watts and a current of 21A, which theoretically should not exceed the capacity of the current wiring. However, the power of the electrical auxiliary heating of the indoor units has been overlooked. Even if only 2 indoor units are operated simultaneously, the power consumption is 7000 watts, and the rated current becomes 32A, requiring a copper core cable larger than 4mm², specifically a 6mm² copper core cable.