In the wire installation, generally the wire has 1.5 square, 2.5 square and so on. Many owners are not very clear about how to choose the square number of wires in the decoration of wires, and they do not know how many square meters of wires the electrical appliances with large wattage can meet. If the square number of wires is not selected correctly, there will be potential safety hazards in electrical appliances. You need to choose the right square number of wires according to the situation of electrical appliances. But the old electrician said that many people chose the wrong one.
Wattage to carry
1. How many watts can 1.5 square wires carry
If the power cord is copper core wire, first, the maximum allowable working current of open wire installation is 20a, that is 4400w; second, the current of concealed steel tube is 16a, and the power is 3520w; third, the current of PVC tube is 14a, and the power is 3000W.
2. How many watts can 2.5 square wires carry
How many kilowatts of electricity can 2.5 square meters of wire receive? According to the national standard gb4706.1-1992 / 1998, the load current value of wire is about 5500 watts for 2.5 square meters of copper wire 16a-25a, and 4400 watts for 2.5 square meters of aluminum wire 13a-20a. It is safe that the voltage of 220VAC does not exceed 10A for a long time, and the most standard is 15A for most of the time.
3. How many watts can 4 square wires carry
Single phase power supply 1kW is about 4.5a, 8kw is about 36a. The current carrying capacity of 4 square wires (single plastic copper wire) is about 30a, which is smaller. Replace 6 square wires (single power supply). Your meter and switch must be larger. Don't use such high power. The minimum power is 4kw. It's OK. How many kilowatts of electricity can be poured by 4 square wires depends on whether you use 220 V power for your family or 380 V power for your factory. If you use 220 square wires, you can load 6 to 8 kilowatts.
How to choose and buy Wires
1. Wire type
I haven't counted the number of types of wires in detail, but there are always dozens. However, there are usually only four kinds of home use: bv line, BVR line, BVVB line and RVV line.
2. Concealed and partially exposed wiring
This kind of wire laying form is called "concealed installation". Not deep buried, but the wire on the wall, the ground surface, known as "surface installation.". BV and BVR wires can be used for all concealed wires and some exposed wires, which are installed through trunking rather than directly exposed to the air.
These two kinds of wires are relatively cheaper, but due to the insufficient strength of their insulation layer, they can not meet the requirements of direct exposure to the air. Bv line is single strand line, commonly known as "hard line"; BVR line is multi strand line, commonly known as "soft line". These two kinds of lines can be selected at will, and there is not much difference in use - there is a small difference, but because the line is too small, it can almost be ignored, so I won't introduce them in detail here.
Of course, the price is not the same, BV line is a little cheaper.
3. Surface wiring
BVVB or RVV wires can be used for all surface mounted wires, including those in trunking, which are also called "sheathed wires". It is to add a layer of insulating skin on the basis of BV line or BVR line (in fact, the standard of the two layers of insulating skin is different from that of BV and BVR lines, but it can be understood in this way for the time being). The number of wires wrapped in the outer insulating skin is different, which can be divided into double core sheathed wire and three core sheathed wire.
For sockets with ground wire, three core sheathed wire is generally used; for sockets with lighting or without ground wire, double core sheathed wire is generally used
1. No wires not connected after wiring. For example, only two wires are connected to a three core sheath wire, and the remaining wire is not connected. This is not allowed.
2. Do not remove the outer insulating skin of the sheath wire, and use the inner wire as bv wire or BVR wire.
BVVB line is single strand hard line, RVV line is multi strand soft line, the difference between the two is similar to bv line and BVR line. However, when using surface mounted wires, more consideration is given to the convenience of construction, so the home users who choose RVV wires are obviously more than those who use BVVB. After all, flexible wires are much more convenient in fixing, bending and other work.
You should know the wattage that different square wires can load. When you choose the square of the electric wire, you should choose the right square of the electric wire according to the wattage of the electric appliance. In this way, it is not easy to have safety problems when using the electric appliance, and you can also save money on the electric wire. Decoration wires, wiring is also a major problem for owners to consider, reasonable choice of wiring, it is not easy to have problems.