Determination of the wire cross section - an overview of effective techniques

The important point is that even if you correctly perform all calculations and select the right product, such a trouble as an accident can still arise. This is due to the fact that not always the cross-section of cores, which is indicated on the marking of wires, corresponds to the actual values. This is only the fault of the manufacturer, because, indisputably, the characteristics do not coincide because of any economic "tricks" in the company. Sometimes the wires and cables on the shelves are generally unmarked, which also casts doubt on their quality.

You ask: "Why should the company spoil its reputation?", Which can immediately find a few logical answers:

1. The plant decided to save on the quality of the goods. For example, if you make a 2,5-milimetre vein thinner by 0.2 mm. Square, you can win several kilograms of metal at 1 running kilometer. In mass production, the economy has decent figures.
2. In the struggle for "a place in the sun," the companies for the manufacture of electrical wiring are trying to entice the consumer, making the price lower than that of competitors. Accordingly, a low price is established due to a slight reduction in diameter( by eye is not noticeable).

As you can see, both are quite reasonable, so it's better to warn yourself and make some simple calculations, which we'll talk about further.

Methods for determining the

There are several ways to determine the cable cross-section. They all boil down to first calculating the diameter of the vein, then using a small calculation to find the final value.

Method number 1 - Devices to help!

To date, there are engineering devices with which you can easily determine the diameter of the wire or cable core. These instruments include a caliper and a micrometer( increase the photo by pressing to view all instruments).

Mechanical micrometer Electronic micrometer Mechanical caliper Electronic caliper

This method of determining the most accurate, but the "reverse side of the coin" is the cost of the caliper / mic. The price, of course, is not cosmic, but for one-time use, it makes no sense to acquire this instrument.

Most often this option is chosen by professional electricians, whose life is directly related to the installation of electrical wiring. Having calipers can most accurately determine the cross-section of the wire in the home. The advantage of this technique is that it is possible to measure the diameter of the veins even on the section of the operating line( for example, in an outlet).

After the measurement it is necessary to use the following formula:

Do not forget that the number "Pi" is 3.14.For maximum simplification of the formula, 3.14 can be divided into 4, after which the calculations are reduced to multiplying 0.785 by the diameter in the square!

Method # 2 - Using the

ruler If you do not want to spend money( and do it right!), We recommend using a simple "grandfather" method to determine the wire cross section by its diameter. If you have a wire, a simple pencil and a ruler, you can find the answer in minutes. All you need is to clean the core of the insulation, then screw it tightly onto the pencil( as shown in the picture) and measure the total length of the winding with a ruler.

The essence of the method is that it is necessary to measure the total length of the wound conductor and divide it by the number of strands. The value that you get is the diameter you need to determine.

Despite its simplicity, the calculations have their own peculiarity:

• the more veins will be wound on the pencil, the more accurate the result, the minimum number of turns - 15;
• turns must be closely pressed against each other so that there is no free space that will significantly increase the error;
• definition must be performed several times( changing the initial side of the measurement, turning the ruler, etc.).Again, the more calculations - the less the error.

We draw your attention to the significant drawbacks of this method. Firstly, only thin conductors( for the reason that a thick cable will be difficult to wind) will be suitable for measurement. Secondly, in the store before buying for this method, you need to purchase a small piece of the product separately.

After all measurements, it is necessary to use the same formula as above.

Method # 3 - Using the

tables Instead of defining the cable cross-section by the formula, you can simply use ready-made tables that will shorten your time and make the result the most accurate.

Tips from the electrician

We have provided the existing methods, but this is far from being all.

We recommend that you familiarize yourself with the following tips from experienced electricians to determine the wire section:

1. In addition to the product section, pay attention to the metal wires. Copper or aluminum core should have a characteristic rich color. If the color is doubtful, then, most likely it is an alloy of metals, which allows you to save the manufacturer your money. Such an alloy is extremely dangerous for the installation of electrical wiring in the house, tk.its current carrying capacity and rated loads are several times less than that of the original product.
2. The cross-section must be determined only on the core. Even if the product looks normal thickness, it is possible that the reduced dimensions of the core were compensated for by an increased layer of insulation.
3. If you doubt the size of the conductor, purchase a larger wire. The power reserve does not damage your wiring!
4. If you are dealing with a cable, the calculation will be slightly changed( due to the fact that the cable can consist of n-th number of wires).In order to correctly perform the calculations, you must first determine the diameter of each individual wire, then sum all the values ​​and select products according to the final number.

Video instruction

We found a very interesting video instruction that shows not only how to determine the wire cross section, but also an illustrative example of the different quality of products from several manufacturers' factories. If you know the Ukrainian language, then the video will be useful to you and will be able to answer any questions, if any!

We hope that now you know how to determine the cross-section of the wire by its diameter. If you have any questions, immediately ask them our experts in the comments or category "Question-answer"!
Also read:

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