Assembly of switchboard is a fundamental stage of the organization of power supply to any room, whether it is a private house, garage or apartment. It is from the quality of installation and the correct selection of components that not only the stability of the work of household appliances depends, but also the safety of residents. Errors at this stage can lead to short circuits, failure of expensive equipment and even fires, so the approach should be as professional and balanced as possible.
Many property owners prefer to trust this task to specialists, but an understanding of the principles of assembly allows you to control the work of electricians and avoid unnecessary costs. Electric shield It takes incoming current from the external network and distributes it to internal consumers, while protecting the lines from overloads. In this article, we will discuss in detail the process of creating a reliable power supply system, starting from the choice of the case and ending with the final testing.
Modern energy requirements dictate their own rules: a simple set of machines is no longer enough. It is necessary to take into account the selectivity of protection, ease of service and the possibility of expanding the system in the future. Well-designed circuit It is not just a set of wires, but a thoughtful logistics of energy flows, where each element performs its function.
Design and selection of components
Before buying equipment, you need to make a detailed wiring plan. You need to clearly know the number of consumer groups: separate lines for outlets, lighting, powerful appliances like cooking panels or boilers. For each group, the total power is calculated, on the basis of which the denominations of protective devices are selected. Use of the differential-automatic Or bundles of automatic plus RCD depend on budget and security requirements.
The choice of the shield is a critical point. They are overhead and embedded, plastic and metal. For residential premises, plastic boxes with DIN-rails are most often used, which are easier to mount and they look more aesthetically pleasing. Metal cabinets with protection class IP65 They are usually placed in garages or on the street, where mechanical strength and protection from moisture are important.
⚠️ Warning: Always leave a margin of free space in the shield (at least 20-30%) for possible addition of new modules in the future.
Don’t forget about the quality of the connecting elements. Comb tires significantly speed up installation and increase the reliability of contacts compared to the lintels of wires. Zero tires (N) and ground tires (PE) will also be required, the number of which depends on the type of RCD used.
Required tools and materials
The quality of the assembly depends on the tool used. You will need a set of screwdrivers with insulated handles, bokos, pliers and a special tool for removing insulation - a stripper. The use of a knife to clean wires often leads to damage to the veins, which is unacceptable when installing power lines.
Pay special attention to the choice of cable. For internal connections inside the shield, use a wire PV-3 (AUD) of the relevant section. It has a flexible multiwire structure, which facilitates stacking and provides good contact. Color markings must be strictly observed: yellow-green for grounding, blue for zero, any other (usually red or white) for phase.
To mark consumer groups and wires, it is recommended to use a special label printer or at least high-quality markers. The chaotic arrangement of wires without signatures will turn the maintenance of the shield into a real nightmare in the future. Cable screeds will help to organize tourniquets and give the assembly a neat look.
☑️ Shield assembly tools
Connection scheme and layout
There are several basic schemes for assembling a switchboard. The simplest is consistent, where all the RCD are after the input machine, but it has a drawback: when the current leaks, the entire apartment is turned off. A more reliable option is group protection, where each RCD serves 2-3 lines. This ensures selectivity: in case of an accident, only the desired area is knocked out.
When assembling modules on the DIN-rail logic from left to right: the input machine, the counter (if installed in the shield), the general RCD or difautomats, then group machines. It is important to keep the distance between the elements for normal air circulation, especially if heavy loads are used. Heat disengagement The machines can warm up during long work.
⚠️ Warning: Never place power cables in close proximity to low-current lines (Internet, TV) without shielding to avoid interference.
The table below shows the approximate distribution of the denominations of machines for a standard apartment:
| Type of consumer | Cable cross-section | The denomination of the machine | Type of characteristics |
|---|---|---|---|
| Lighting | 1.5 mm2 | 6-10 A | B |
| Rosettes (rooms) | 2.5 mm2 | 16 A | C |
| Cooking panel | 6 mm2 | 32-40 A | C |
| Air conditioner | 2.5 mm2 | 16-20 AA | C |
Why is the characteristic "B" or "C" important?
Automatic machines with the characteristic "B" are more efficient at small overloads and are suitable for lighting. Characteristics "C" withstands short-term initiation currents, characteristic of engines and powerful devices.
Step-by-step assembly instructions
Start installation only after a complete power outage at the input. Install DIN-rails in the case and fix all modular elements according to the developed scheme. Do not tighten the terminals to the end at once – first assemble the entire structure, check the geometry, and then make the final stretch of contacts with the recommended effort.
Preparing the wires requires accuracy. Remove the insulation strictly to the length of the contact area, so that the excluded parts do not dangle and do not create a risk of short circuit. When using comb tires, trim them to the desired size and close the ends with plugs. Puff moment The contact must comply with the manufacturer's recommendations.
Formation of bundles of wires is carried out using cable ties, trying to avoid sharp excesses. Phasic and zero wires should go in parallel, without twisting. After connecting all consumers, check the compliance of the scheme: phase should come to the upper terminals of the machines (unless otherwise specified by the manufacturer), and zero - to the corresponding bus.
System verification and testing
Before applying the voltage, conduct a visual inspection of the assembly. Make sure there are no sticking veins, all screws are tightened and the wires lie flat. Check the resistance of insulation with a megaohmmeter if possible, especially in new homes where wiring may have been damaged during construction.
Turn on the power in stages. First apply the voltage to the input machine and check for phase at the output terminals. Then turn on group machines alternately, controlling the absence of sparking and extraneous sounds. Testing of the RCD is done by pressing a button "Test."This should result in instantaneous chain shutdown.
If the shield is properly assembled, it should work silently. Heating of machine cases is permissible only within the normal range (warm state), but not hot. If you detect any abnormalities, turn off the power immediately and look for the cause. The first run should always be conducted under the supervision of an experienced electrician if you are doing it for the first time.
High-quality assembly of the shield eliminates heating contacts and ensures the stable operation of the entire power grid for decades.
Frequent errors in installation
One of the most common mistakes is bad contact tightening. Over time, aluminum and copper have the property of "leaking", weakening the compound, which leads to heating and burnout. Another mistake is a violation of color markings, when blue wire is used as a phase, which is confusing when repairing.
Often we forget about the separation of zeros. If you have several RCDs, then for each of them you need a separate zero bus. Combining zeros of different groups leads to false positives of the defense. Also, do not save on the length of the wires inside the shield - a reserve of 10-15 cm will facilitate the alteration or replacement of elements.
Ignoring the rules of selectivity leads to the fact that when a short circuit in the socket knocks out a common machine, curling the whole house. Correctly selected denominations and time-current characteristics allow you to localize the accident only in the problem area.
Do I need to seal the shield after assembly?
Sealing is required only on the introductory machine and the electricity meter, if they are in the same box. There is no need to seal the internal machines, as they are the property of the consumer.
Can I use a higher-denomination machine if I knock out the old one?
Absolutely not. The machine protects the cable, not the device. If you put the machine more powerful than the cross-section of the wire allows, the wiring will burn when overloaded, and the machine will not even click.
How often should I check the tightening of contacts in the shield?
It is recommended to carry out preventive stretching of contacts every 1-2 years, since under the influence of temperature cycles, the screws can weaken.