First of all, many electric workers do not know how the current can be carried by the electric wire and how to convert power. I will explain to you, the power of the single -phase electrical appliances P = UI (this is a blocking load, the sensual load is P = UICOS, you can ignore it) This is the knowledge of junior high school. 1KW is a 4.5 current. For example, the air conditioner 1.5P air conditioner is 2kW, then the current is about 9A. If the conversion power of the three -phase power is p = √3UICOS (here is 0.75), then I = 1000/1.732 * 380 * 0.75. Therefore, the 1kW of three -phase electricity is about 2A. Of course, it is actually necessary to take efficiency.

Then let's take a look at the carrier current of the wire and cable. In fact, you can receive it on the Internet. Xiaobian will sort it up here. The following formula is the aluminum line calculation method.

Twenty -five or five; (one hundred square meters of cables * 2, 10 square meters are multiplied by 5, for example, 4 square meters are 20A)

Twenty -five, three five, four triads;

7095 times and half; (2.5 times 70 and 95 square meters)

80 % off the temperature of the pipe; (this is a good understanding, we directly multiply 0.72)

Copper thread upgrades; (still take four square meters as an example, then use 6 square meters, 1.5 is 2.5, 2.5 is 4 square meters)

Add half of the naked line. (No need to watch, the overhead cable -free nude line)

Through the above pilot, we know that aluminum lines are rarely used now, most of which are mainly copper lines. Then the 4 -square meter calculation method is a 6 -square -meter calculation method, which is the computing algorithm to the upper level cable. There is also a formula in the actual operation of Xiaobian.

Then the 4 -square -meter line can withstand a current of 30A (the wires are basically passed through the tube, the external temperature is high, so it is only 0.72 times), the single -phase electricity is 220V * 30A is 6600W; the three -phase electricity is 15kW, which is very simple. no. Xiaobian is based on the installation or maintenance or decoration of daily electricians. Of course, the electric heating is different (the single phase is 4 times, and the three -phase is 1.5 times the power).