如何根据电机大小选择电缆线径（How to select cable diameter according to motor size）.doc

如何根据电机大小选择电缆线径（How to select cable diameter according to motor size） Common electrical calculation formula The first chapter is one of the formula of calculating current by power 1. Application: This is the formula for calculating the current (ampere) based on the power (kw or kva) of the electrical equipment. The magnitude of current is directly related to power, and it is also related to voltage, phase, force rate (also known as power factor). There is generally a formula to calculate, since the factory often USES 380/220 volt three-phase four-wire system, therefore, yes The current is calculated directly according to the magnitude of the power. 2. Key words: low voltage 380/220 volt system per KW current, Ann. Kw, current, how do you calculate it? Double the electricity, half the electricity. Single-phase kw, 4.5 Ann. Single phase 380, current two-and-a-half. Explanation: the key is the three-phase device in the 380/220v three-phase four-wire system To calculate the number of ampere per kilowatt. For some single-phase or voltage different single-phase sets The number of each kilowatt per kilowatt. In these two words, power refers to the motor, which is at 380V The current of the motor is about 2 ampere per kilowatt The current is also called the rated current of the motor. [example 1] 5.5kw motor is electric current of 11. [example 2] 4 0 kw water pump motor is 8 0 ampere as the electric power double. Electric heat is a resistance furnace that is heated by resistance. Three phases 380 volts of electricity The current of the equipment is 1.5 ampere per kilowatt. The kw number plus half (multiply by 1.5) is the current, ampere. [example 1] 3 kw electric heater is a current of 4.5 ampere according to electrothermal plus half. [example 2] 1 5 kw resistance furnace is 2, 3 ampere as the electric current is heated. This formula does not specifically refer to electric heat, but also for lighting, although light bulbs It is a single phase instead of three phases, but the