How to collect a shield with automatic machines in the house with your own hands: a complete guide

Electric shield is the heart of the power system of any home, whether it is a spacious country cottage or a compact apartment. The quality of its assembly directly depends on the safety of residents and the safety of expensive household appliances. Many property owners wonder if it is possible to assemble this design on their own without resorting to the services of expensive electricians. This is theoretically possible, but requires a deep understanding of the physics of the process, strict adherence to the rules, and the availability of a quality tool.

Before you start purchasing materials, you need to clearly understand that electricity does not forgive mistakes. Incorrect load calculation or poor contact can lead to fire wiring or electric shock. In this article, we will discuss all the stages of creating a reliable switchboard, from design to final connection. We will pay special attention to the choice of components and typical mistakes that beginners make.

Scheme design and load calculation

Any work with electricians begins long before the purchase of the first machine. The first step is to create a detailed single-line power supply. At this stage, it is necessary to determine the number of consumers, their power and divide them into logical groups. For example, bathroom outlets, lighting, kitchen appliances and air conditioners must be powered through separate lines of protection. This will localize the problem in the event of a short circuit, leaving the rest of the house with electricity.

The loads are calculated based on the maximum power of the devices that can be switched on simultaneously. For a standard apartment or house, automatic machines with a nominal value of 16 Ampere for rosette groups and 10 Ampere for lighting are often used. However, for powerful consumers, such as cook-panel or boilerseparate lines are required with the calculation of the cable cross-section and the nominal protection individually. It is important not to overload one phase, distributing consumers evenly if a three-phase voltage enters the house.

There are several typical assembling schemes of the shield, the choice of which depends on the budget and safety requirements. A simple scheme can include only an introductory automatic and group protection automata. A more advanced option involves the installation of a RCD (protective shutdown device) on each group or the use of differential machines. The use of selective RCD at the entrance allows you to avoid turning off the entire house when current leaks in one line.

When designing, the reserve of space in the shield is also taken into account. Experienced electricians recommend filling the box body by no more than 70-80%. This is necessary for better air circulation and the possibility of adding new modules in the future, such as a voltage relay or timer. Ignoring this rule can lead to overheating of components in the summer.

Selection of equipment: automatic machines, RCD and difautomats

The quality of the panel assembly directly depends on the components used. The market is full of offers, but it is absolutely impossible to save on security. The base of the shield is switch-offThey protect the wiring from overloads and short circuits. When choosing, you should pay attention to the disconnecting ability, which for household needs is usually 6 kA (kiloamper). This means that the machine is guaranteed to break the circuit even with a very strong short circuit current.

Protective shutdown devices (RCD) are used to protect a person from electric shock. They react to the difference in currents of incoming and outgoing streams, acting when a leak occurs, for example, if a person touches a bare wire. The nominal value of the leak for residential premises is 30 mA (milliamper). There are also differentialwhich combine in one body the functions of a conventional automatic machine and RCD. This is convenient for saving space in the shield, but such devices usually cost more.

⚠️ Warning: Never use a 100mA or 300mA leakage ultrasound to protect the socket groups in living rooms. These denominations are intended only for fire protection at the entrance to the house.

An important element is also cross-module or a comb tire, which allows you to conveniently distribute phase and zero in groups of machines. The use of homemade jumpers from wire clippings (combs) is permissible, but requires high qualification installation. Ready-made copper tires provide reliable contact and aesthetic appearance.

Comparative table of the main protection devices will help to make the right choice:

The device	Protection against overload	Protection from the KZ	Protection against current leakage	Position(s) to be occupied
Automatic switch	Yes.	Yes.	No.	1-3
UZO (Protective shutdown device)	No.	No.	Yes.	2-4
diffautomatic	Yes.	Yes.	Yes.	2-4
Voltage relays	No.	No.	No (U racking only)	2-3

Required tool and supplies

For a high-quality assembly of the electric shield is not enough just to have a desire. You will need a professional tool that will provide a reliable connection of contacts. The main instrument is clamp-tick (crimper) for the tips and stripper To clean the insulation without damaging the vein. The use of a knife or bogocreas for cleaning often leads to copper bites, which at the point of contact causes heating and eventual melting.

To connect multi-core wires, it is necessary to use NSHVI tips (Tip Shtyreva Buss Isolated). It is impossible to pinch the "fluffy" wire in the machine directly - the contact will be unstable. The tips are pressed by ticks and provide a monolithic connection. Also, screwdrivers with a voltage indicator, bokorez, roulette and marker for marking will be required.

• 🔧 A set of dielectric screwdrivers with a flat and cross sting.
• ✂️ Stripper for cleaning insulation of different diameters.
• 🔌 Climbing ticks (crimper) for NSHVI tips.
• 📏 Roulette, level and marker for markup.
• 🧤 Dielectric gloves and mat (for safety during inspection)

Special attention should be paid to consumables. In addition to automatics, you will need DIN racks, zero bus (N) and ground bus (PE). For internal switching, a PV-3 (POGV) mounting wire of the corresponding cross-section is used, usually 10 or 16 mm2 for inlet lines and 2.5 mm2 for lintels. Color marking of wires should be strictly observed: yellow-green for grounding, blue for zero, white/brown/black for phase.

Procedure for assembly and installation of components

The assembly of a shield is a process that requires consistency and accuracy. All work is carried out on a completely de-energized shield. The first step is to fasten the DIN-rail inside the housing. It is installed all modular elements: the input machine, the counter (if provided in the shield), UZO, automatics of group lines and voltage relay. The arrangement of the elements is planned in advance according to the scheme.

After installation of modules on the rack, their disconnection is made. There are two main methods of switching: comb tyre and separate jumpers. The comb looks more aesthetic and reliable, but requires careful selection for a specific series of machines. The wire jumpers are more flexible in terms of configuration, but require high-quality crimping and stacking.

An important step is the organization of zero and ground tires. Zero wires from the RCD should come on separate zero tires corresponding to each group. Grounding wires (PE) are reduced to a common ground bus, which in turn connects to the shield body and the external ground circuit. Connecting zero and earth after the input machine is strictly prohibited.This will trigger the RCD.

When laying wires, try to avoid bundles that block access to the screws of the machines. The wires must run parallel to the DIN-rail, turning at right angles to the contacts. Not only is it beautiful, it also provides better cooling and ease of service. Excess wire length is better left in reserve behind, carefully folded, than to make tight stretched loops.

Typical errors in the assembly of the electric shield

Even experienced masters sometimes make mistakes, let alone beginners. One of the most common problems is poor contact. Insufficiently tightened screw machine leads to heating, charring insulation and possible fire. Therefore, after assembly, it is recommended to re-stretching all contacts after a while, when the metal will slightly "sit down".

Another common mistake is the confused phase and zero at the entrance to the RCD or difautomat. In most devices, the input terminals are marked with the number "1" or the letter "L / N", and the output terminals are marked with the letter "2". If you confuse the input and output, the device may burn or fail to perform a protective function. It is also dangerous to combine the zeros of different groups protected by different RCDs – this will lead to false positives.

⚠️ Note: Do not use aluminum wire for internal wiring of the shield. Aluminum has the property of "flowing" under load, the contact weakens, which inevitably leads to overheating. Just copper!

There is often a lack of selectivity. If the entrance is a 100 mA RCD, and there are no groups of them or they are also 100 mA, then with any leak the whole house will be knocked out. It is necessary to put the RCD at 30 mA on groups and, if necessary, selective RCD at 100-300 mA for input with delayed response time.

The lack of marking is another scourge of homemade shields. After a year, you may forget which machine is responsible for what. Be sure to sign each machine outside on a special sticker or diagram attached inside the shield door. This will save you a lot of nerves in an emergency.

What to do if the machine is warm?

If the circuit breaker is warming but not turning off, check the screw tightening. If the screws are tightened, perhaps the nominal value of the machine is chosen less than the wiring allows, or there is a bad contact (sparkling) in the circuit. In rare cases, the device itself may be damaged, then it must be replaced.

First start and check of operation

After the installation is completed, the most important moment comes - the first launch. Before applying the voltage, visually inspect the shield again. Make sure there are no fallen washers, wire clippings or tools inside. Check that all machines are turned off (handle down).

Put the voltage on the introductory machine. If you are established voltage-relayIt should show the presence of phase and allowable voltage. Now it is possible to turn on the automatics of group lines in turn. First, the lighting machine is turned on, then the sockets, then the powerful consumers. When turning on each machine, listen to the click - it should be clear, without buzzing.

• 👁️ Visually check for no sparkling at the time of inclusion.
• 👂 Listen to the outside sounds (buzzing, banging).
• 🖐️ Carefully (with the back of your hand) check the heating of the machines after 15-20 minutes of work under load.
• 🔌 Check the operability of the RCD button "Test" on each device.

Checking the RCD button "Test" is mandatory. Pressing this button simulates a current leak, and the machine must instantly shut down. If this does not happen, the device is faulty and requires replacement. It is also advisable to check the differential protection with a special device, but in everyday life are often limited to the standard button.

Maintenance and safety of operation

The collected shield requires periodic attention. About once every six months, it is recommended to conduct an external inspection: whether there is a smell of burning, heating, dust. Dust in combination with humidity can conduct current, so once a year or two shield is desirable to gently blow through the compressed air (with power off!).

The safety of the operation also depends on the behavior of the occupants. You can not glue the vents of the shield, hang clothes on it or clutter access. If the machine is knocked out, you can not immediately turn it on again. First, you need to analyze what was turned on at the time of disconnection, turn off powerful devices, let the machine cool down (5-10 minutes) and only then try to turn on again.

If you notice that the machine starts to knock regularly even with a small load, this is a signal of a problem. Perhaps somewhere damaged insulation in the wall or failed electrical appliance. Ignoring these signals and, especially, replacing the machine with a more powerful one ("so that it does not knock out") is a direct way to fire. The machine protects the cable.If it works, the cable is in danger.

Can you replace the machine with a more powerful one if it is constantly knocked out?

Absolutely not! The automatic switch is selected strictly by the cross section of the cable. If the cable can withstand 16A, and you put the machine on 25A, then when the cable is overloaded, the cable will start to warm and melt, and the machine will not even click. This will lead to a short circuit and fire. The solution is to look for the cause of the overload or change the wiring to a more powerful one.

Do I need to change my machines every 10 years?

The service life of high-quality machines is 10-15 years or more. However, the mechanical resource (the number of positives) is limited. If the machine has never been triggered by a short circuit current and has not warmed, a planned replacement is not required. But if it has frequently knocked out or worked with overload, it is better to replace it, as the thermal cleavage could degrade.

Which is better: one RCD for the whole house or for each group?

One RCD is cheaper for the whole house, but any leak (even in one socket in the kitchen) will cause the light to disappear throughout the house, including the refrigerator and boiler. Installing an RCD on each group (or several groups) is more expensive and takes up more space, but provides comfort: if the problem turns off only one line, and the rest of the house will work.

Why do I need to contact N and L on the machine when I have one phase?

On a single-pole machine, there is usually only one contact for the phase. If you see the N marking, it means it's a two-pole machine or a RCD. In a single-phase network, both phase and zero are broken through a two-pole automaton. This increases security during maintenance, as it completely cuts off the apartment from the network. Connect strictly according to the scheme: L (phase) and N (zero) at the entrance and exit.