Replacing an old switchgear or installing a new one begins with the removal of the cover and visual assessment of the inlet cable and existing circuit breakers. In old houses, there is often a twisting of wires at the entrance, which is fire-prone and requires immediate removal before work begins. Before any manipulations, it is necessary to completely de-energize the apartment, turning off power on the driveway shield or cutting the introductory cable if access to it is limited.
After the voltage is relieved, the integrity of the insulation of the suitable wires should be checked and their cross-section corresponds to the planned load. If the copper wire has a cross section of less than 4 mm2, the installation of powerful consumers in the apartment can lead to overheating of the track. Aluminum wires require special attention: they are brittle and prone to oxidation, so they can not be directly connected to the copper terminals of modern switch-off without the use of special transitional sleeves or terminals.
The choice of place for installation determines the type of housing: embedded models are used for hidden wiring, and hinged models are used for open ones. The dimensions of the niche should allow free placement of all elements, taking into account the margin for bending the cables. The standard depth of modern boxes is 100-150 mm, which allows you to carefully lay the wires behind the DIN-rail.
⚠️ Attention: It is strictly forbidden to start the assembly of the shield without first turning off the voltage at the input. Working under current is deadly and can lead to short circuit.
Selection of components and calculation of the number of modules
Proper installation of an electric shield is impossible without a correct calculation of the number of seats or modules. Each element takes up a certain number of standard modules (18 mm), and an error in the calculations will cause the housing to have to change or leave empty holes. The basis of the system is the input machine, the protective shutdown device (CCD) or difaute machines and group machines for lighting lines and sockets.
A single-phase network of a standard apartment usually requires the following configuration: a two-pole input automaton, one common RCD or several separate ones, and a set of single-pole machines at 16A for sockets and 10A for light. It is also necessary to provide a place for a voltage relay that will protect the equipment from surges in the network, and possible spare spaces for future connection of the air conditioner or electric stove. It is important to use only certified components from well-known brands, such as: ABB, Legrand or IEK.
When planning the scheme, it is worth laying a reserve of 15-20% of the estimated number of modules. This will allow in the future to add a new line or replace the device with a more overall one without replacing the entire body. The tight layout makes air circulation difficult and can cause contacts to overheat under load.
- 🔌 Introductory automatic - 2 modules for a single-phase network.
- ⚡ UZO or differential machine - 2-4 modules.
- 💡 Lighting machines - 1 module each.
- 🔌 Automatic outlets - 1 module each.
Tools and preparation of the site
High-quality installation requires the presence of a specialized tool, without which the installation of the shield will turn into torture. The main working tool is a screwdriver with a set of bits, including cross and slit, as well as a dynamometer screwdriver for the final stretch of contacts. For cutting wires and cleaning the insulation, it is necessary to use a stripper, which does not damage the vein, unlike a regular knife.
To fasten the body in the niche, a drill drill, dowel and screws will be required. If the wall is concrete, the drilling takes the main time, so the battery charge should be full. Bokosnips are also needed to trim the excess length of wires and cable ties, as well as a voltage indicator for double checking the absence of current before starting work.
Preparation of the landing site includes cleaning the niche from construction debris and leveling the edges. If the niche depth is insufficient, you may have to choose an additional layer of plaster or use an overhead shield. Before installing the case, it is recommended to try on the DIN-rail and make sure that the cables freely reach the place of attachment of the machines with a margin.
Use paint tape to temporarily lock the DIN rail in the right position before the final fastener. This will make it easier to fit and assemble the circuit.
Installation of the body and fastening of DIN-recks
Installation of the body of the shield is made strictly according to the level, since the distortion is visually striking and can complicate the installation of equipment. Embedded models are fixed in the niche using a plaster mixture or mechanical fasteners included in the kit. The hinged shields are attached to the dowel-nails or screws directly to the wall through holes in the rear wall of the housing.
After fixing the base inside, DIN-rails are installed - metal profiles on which all modular devices are snapped. The distance between the rods should ensure convenient supply of cables from above and below. Often complete with the shield are plastic plugs and combs, which must be installed before installing the machines.
| Element | Type of attachment | Tool. | Nuance editing |
|---|---|---|---|
| Corps | Dubel/Self-rears | Perforator | Strictly level. |
| DIN-ride | Screws to the hull | Screwdriver. | Grounding the Reiki |
| Automatics | Latch on the rack | Hands/Flat screwdriver | Before you click. |
| Zero tire | Vint/Reiki | Screwdriver. | Insulation from the hull |
An important step is the organization of zero and ground tires. In modern shields, separate places are reserved for them or special racks are used. Connection of metal shields with the contour of the grounding of the house is a mandatory requirement PUE (Rules of electrical installations).
☑️ Pre-assembly check
Circuit assembly and machine connection
Assembly of the internal filling begins with the installation of the introductory machine and the RCD on the top of the DIN-rail. Then group machines are mounted in a logical order corresponding to the scheme. Fixation occurs by simply pressing until a characteristic click, and a special lock at the bottom of the device is used for dismantling.
Connection of machines with each other is most convenient to perform using a copper comb, which provides reliable contact and aesthetic appearance. If there is no comb, jumpers from the same wire section as the suitable cable are used. Screwings inside the shield are strictly prohibited, all connections must be made through the terminals of automatic machines or special cross-modules.
When connecting, it is important to follow the color marking: phase wires (L) are usually brown, white or black, zero (N) are blue, and grounding (PE) are yellow-green. Confusing zero and phase at the entrance to the RCD will lead to its instantaneous operation or failure. The phase wire from the input machine is distributed to the combs of group automatic machines, and zero goes to the corresponding bus or the output of the RCD.
⚠️ Note: Aluminum wires cannot be directly inserted into the terminals of the machines. Use bimetallic adapters or change the input area to copper.
Procedure for connecting the comb
First, cut the comb under the right number of teeth, then insert into the slots of the machines to the end, close the end plugs and only then tighten the terminals.
Wire switching and final assembly
Connecting the outgoing lines requires accuracy and compliance with the length of the loops. The wires should not be stretched, but the excessive length will prevent the door from closing. It is optimal to form bundles of wires, fixing them with cable ties, and bring a separate sling to each machine.
Cleaning of the insulation should be carried out at the length indicated on the body of the machine (usually 10-12 mm). If you clean too little, the insulation will come under contact, causing heating. If too much, the bare part of the wire can stick out from the side, creating a risk of short circuit. For multi-core wires, it is mandatory to use NSHVI tips.
After connecting all lines, the initial draw of contacts is made. After 15-20 minutes of operation under load (including electrical appliances), it is recommended to re-check the tightening of the screws, since copper tends to settle slightly. Then a protective panel (cover) with cutouts under the levers of the machines is installed.
- ✂️ Clean the wire strictly to the depth of the terminal.
- 🔧 Use a dynamometer screwdriver to control the effort.
- 🏷️ Sign each machine with a marker on the diagram in the door.
- 🧹 Remove the wire clippings from the case before closing.
The quality of the assembling of the shield determines the fire safety of the entire apartment. Don’t skimp on components and pay attention to each terminal.
Performance check and launch
The final stage is to check the assembled circuit before applying the voltage. Visually make sure that all wires are connected according to the scheme, there are no dangling ends and bare sections. Check that the introductory machine and the RCD are in the off state.
The supply of voltage is carried out only after all residents are warned about the work. First, the input machine is turned on, then the presence of voltage at the entrance of the RCD is checked. After that, the RCD itself is turned on and alternately each group automatic with control of the presence of voltage at the output.
Be sure to check the operability of the "Test" button on protective shutdown devices. Pressing this button should result in instantaneous shutdown of the circuit. If the RCD does not work, it must be replaced, as it does not perform its protective function. It is also recommended to check the operation of each socket and switch in the apartment.
Can I install a shield in the bathroom?
Installation of switchboards in bathrooms, saunas and other wet rooms is prohibited by the rules of the PUE. The shield should be in a dry area, corridor or separate technical room.
Do I need to fill the apartment shield?
The sealing of the introductory machine is required only if it is in the general house shield or is a point of account. Inter-apartment panels do not need to be sealed, the owner of the house has access to them.
What to do if the machine is constantly knocking?
The reasons may be in network congestion, short circuit or malfunction of the machine itself. First, turn off all the appliances and try to turn on again. If the problem persists, call an electrician to diagnose the wiring.
What IP protection class is required for the shield?
For living rooms (living room, bedroom) IP30 or IP40 is enough. If the shield is installed in an area with high dust or humidity (garage, basement), IP54 and higher is recommended.