The second table is for cables installed by Method C, "clipped direct". As you can see there is quite a difference in rating so be absolutely sure you are doing the right thing.

10mm Cable | 10mm Electrical Cable | Screwfix

It is worth engaging with a qualified electrician early so that you and they can agree how they will approve and then certify the work. After all it is their name on the certificate so if they are not 100% happy that they know that everything is perfect, they will not sign it off, simple as that! Resistance can be thought of as electrical friction and the wires in the cable or flex will absorb some of the energy in the current, allowing a little less to reach the target than was sent.The first table below is for cables which are installed by Method 103 “Surrounded by thermal insulation including in a stud wall with thermal insulation with cable not touching the wall”. To calculate the area of a circle multiply the radius (half the circle diameter) by itself to get the radius squared. This is then multiplied by Pi (Π) which is approximately 3.142. This calculation is written as shown in the image below.

Cables (Copper Conductors) Current Carrying Capacity (Amps) of Cables (Copper Conductors)

In most instances, the size of cable should be printed on the sheath, but if not you will need to calculate the diameter of the wire to determine its size, which means working out the area of a circle e.g. the circular piece of wire.

A cable can carry many wires depending on the job it needs to do. Most domestic cables carry a blue wire which is usually for the neutral current, a brown wire for a live current and a bare wire to take residual current to earth. This cable is called 2 core and earth, or twin and earth. Table 4E1B | Voltage Drop Single-Core 90°C Thermosetting Insulated Cables, Non-Armoured, with or without Sheath With this in mind, ultimately it is the appliances or items that will draw power from the circuit they are powered from and the location in which cables will run that decides on the size of cable required. What Size Cables for Lighting Circuits? The standards for electrical safety in electricians tools are set by a committee in Germany called the VDE or Verband der Elektrotechnik and they are very stringent as one would expect. The methods mentioned in the table below are methods for how the cable runs through the home to carry the power from the consumer unit to the outlet.

Single-Core 90°C Table 4E1A - Current Carrying Capacity Single-Core 90°C

Another cable used a lot in domestic lighting is called 3 core and earth. The extra core (wire) is in an insulating sheath and is used as an extra conductor to carry power between 2 or more switches operating lights. Single-Core 90°C Thermosetting Insulated Cables, Non-Armoured, with or without Sheath - Table 4E1A Current-carrying Capacity (amperes): Table 4E1A | Current-carrying Capacity Single-Core 90°C Thermosetting Insulated Cables, Non-Armoured, with or without SheathAside from the 3 most commonly used cable sizes of 1, 1.5 and 2.5mm twin and earth there are in fact numerous other larger sizes of cable that include 4mm, 6mm, 10mm and 16mm. These are mostly used for appliances and objects that require much more electrical power to operate or special use situations. Even larger sizes of cable include 25, 35, 50, 70,95, 120, 150 all the way up to 1000 square mm, over 20 different sizes in total, but anything above 16mm is generally just for industrial use.