The electrical distribution board is the central point of every installation — it houses all protection devices and distributes circuits throughout the building. Choosing the right switchboard affects safety, ease of maintenance, and future expandability.
Types of Switchboards
Three main designs are available on the market:
- Surface-mounted boards — installed on the wall surface, easy to fit, ideal for garages, basements, and utility buildings,
- Flush-mounted boards — recessed into the wall, aesthetically pleasing, the standard choice in new residential construction,
- Free-standing modular cabinets — large-capacity enclosures (over 120 modules), used in commercial and industrial buildings.
How Many Modules Do You Need?
One module equals a width of 17.5 mm on the DIN rail. Typical requirements:
- 2-room apartment: 24–36 modules,
- detached house: 48–72 modules,
- house with PV, heat pump, and EV charger: 72–96 modules.
Rule of thumb: always plan for 30% spare capacity for future circuits. Adding a new circuit to a full board means an expensive enclosure replacement.
Manufacturers and Quality
Proven modular equipment brands:
- Hager — Golf series (residential), Volta (industrial), high-quality rails and terminals,
- Schneider Electric — Pragma, Kaedra series; comprehensive Prisma distribution systems,
- Legrand — Nedbox, Plexo series; excellent IP65 surface-mounted solutions,
- ABB — Mistral, AT/U series; robust equipment with wide availability.
What Should Be Inside the Board?
A properly equipped residential distribution board includes:
- Main switch (isolator) — allows disconnection of the entire installation,
- Residual current devices (RCD) — minimum two, 30 mA, Type A,
- Miniature circuit breakers (MCB) — one per circuit,
- Surge protection device (SPD) — class T1+T2 with upstream backup fuse,
- PE and N busbars — separate bars with an adequate number of terminals.
Installation and Labelling
Every circuit should be documented on a diagram placed inside the board door. Internal wiring should be routed through cable ducts, and connections made using busbar comb connectors rather than wire jumpers. This approach is clear, safe, and simplifies future diagnostics.