Before we move on to the main content, we ne to understand what we want to calculate, the cross-section of a wire or a cable, what is the difference between one and the other!? Despite the fact that the average person uses these two words as synonyms, meaning something of their own, but if we are meticulous, there is still a difference.
So a wire is one conductive core,
It a single core or a set of conductors, insulat in a dielectric, in a sheath. But a cable is already several such wires, unit into a single whole, in its physician data and insulating sheath. In order for you to better understand what is what, look at the picture.
So, now we know that we ne to calculate the cross-section of the wire, that is, one conductive element, and the second will go from the load back to the most common mistakes when choosing a smartphone power supply.
However, sometimes we ourselves forget ourselves no better than you, so if you catch us saying the word cable somewhere, don’t take it for ignorance, stereotypes do their job.
Selecting a cable
It is best to make internal wiring from copper wires. Although philippines numbers ones are not inferior to them. But there is one nuance here, which is associat with the correct connection of sections in the distribution box. As practice shows, the connection points often fail due to oxidation of the aluminum wire.
Another question: which wire to choose: single-core or multi-core? Single-core has better current conductivity, so it is recommend for use in household electrical wiring. Multi-core has high flexibility, which allows it to be bent in one place several times without compromising quality.
Single core or multi-core
When installing electrical wiring, wires and cables of the PVS, VVGng, PPV, APPV brands are usually us. This list includes both flexible cables and those with a single core.
Here we would like to tell you one thing. If your wiring is not going to move, i.e. it is not an extension cord, not a bend that constantly changes its position, then it is preferable to use a single core.
You ask why? It’s simple! No matter how well the conductors are laid in the protective insulating braid, air containing oxygen will still get under it. The copper surface oxidizes.
As a result, if there are many conductors,
The oxidation area is much larger, which means the conductive cross-section “melts” much more. Yes, this is a long process, but we do not think that you are going to change the wiring often. The longer it works, the better.
This oxidation effect will be especially pronounc at the ges of the cable cut, in rooms with temperature differences and high humidity. So we strongly recommend that you use a single-core! The cross-section of a single-core cable or wire will change slightly over time, and this is so important for our further calculations.
Copper or aluminum
In the USSR, most residential buildings were equipp with aluminum wiring, it was a kind of norm, standard and even dogma. No, this does not mean that the country was poor and did not have enough copper. In some cases, it was even the opposite.
But apparently the designers of electrical networks decid that it would be possible to save a lot economically if they us aluminum instead of copper. Inde, the pace of construction was enormous, it is enough to recall the Khrushchev-era buildings in which half of the country still lives, which means that the effect of such savings was significant. There is no doubt about it.
However, today there are different realities, and aluminum wiring is not us in new residential premises, only copper. This comes from the PUE standards, clause 7.1.34 “Cables and wires with copper cores should be us in buildings…”.
So, we strongly advise you not to experiment and try aluminum. Its disadvantages are obvious. Aluminum twists cannot be solder, it is also very difficult to weld, as a result, the contacts in the distribution boxes can be damag over time. Aluminum is very fragile, two or three bends and the wire falls off.
There will be constant problems with connecting it to sockets,
switches. Again, if we talk about the conduct power, then a copper wire with the same cross-section for aluminum 2.5 mm. sq. allows a continuous current of 19A, and for copper 25A. Here the difference is more than 1 kW.
So, let’s repeat once again – only copper! Further, we will proce from the fact that we calculate the cross-section for copper wire, but in the tables we will also provide values for aluminum. You never know.