Help me choose a cable for connecting a business building

Anatoly asks:

Good afternoon. Please tell me which wire is better to choose, a house and a building with a distance of 25 meters, in the building there are 2 boilers, a pump station, an electric stove 2 burners, a microwave, a refrigerator, a kettle. Cable laying will be underground, what section to choose and type ?! Thank.

The answer to the question:

Hello! I hope I understood your question correctly and you want to lay a line from the house to the building in order to electrify it

To select the sections you need:

1. Decide what par value your introductory machine has.

2. It will be determined which machine you put at the beginning of the line. Its value should not be more than the opening machine, maybe less, look at the power of the equipment and how many devices you will turn on at the same time. Suppose you enter a single-phase 25A, it means that it is rational to put the same 25A with your equipment at the beginning of the line to your building, because, for example, 16A will be clearly small, for example, the pump station will not start when the boiler is on and will knock out the machine.

In this case, you do not just need to add up the power of all devices and read the total current, most likely we will get fantastic numbers, we need to proceed from the available current strength limited by the input circuit breaker.

3. Determined with the gasket. Since you will be laying underground, it is rational to use a cable such as the standard VVGNG-LS and lay it in a rigid HDPE pipe. It is also possible to lay armored cables without pipes, for example VBBSHV. Of course, it is possible to lay VVG in the ground without a pipe, and so many often do at home. But provided that there are no increased loads in the laying areas, for example, the car’s entrance to the yard and the like, and there are no sharp objects (stones, debris, etc.) in the ground, and you will also remember the laying route to avoid cable damage in case of any excavation. But better, after all, in the pipe.

4. After selecting the machine, you can already select the cable cross section for current and losses, for example, using online calculator, or “estimate” according to table 1.3.4. of chapters 1.3. PUE.

I hope I clearly answered and correctly understood your problem!

Ask your question Answer the question