5 kW Three-Phase Generators

A three-phase generator supplies three voltages shifted by 120°, giving 400 V between phases and 230 V between a phase and the neutral conductor — it can power both 400 V three-phase motors and ordinary 230 V equipment. A single-phase generator has only one 230 V output and cannot run three-phase motors at all. A 5 kW three-phase model also lets you spread single-phase loads across 3 phases, cutting the risk of overloading a single line.

Power is sized by adding up the demand of equipment running at the same time and allowing headroom for motor starting current — 3 to 5 times higher than rated power at switch-on. A typical set of construction tools (drill, angle grinder, lighting) rarely exceeds 3–4 kW of continuous load, so a 5 kW generator leaves a safe margin. For several higher-power motors running together, the 10 kW segment is worth considering instead.

A 5 kW three-phase generator has a 400 V socket (most often 16 A or 32 A, 5-pin with an earth pin) and usually additional 230 V sockets for single-phase equipment. Connecting three-phase loads requires a 5-core cable (3 phases, N, PE) matched to the generator's socket, but the site installation itself doesn't need to be elaborate — a construction distribution board with residual-current protection is enough.

Price depends mainly on voltage stabilization (AVR), brand and equipment level — a non-AVR model tends to cost less than a stabilized version built for sensitive electronics. Engine class and fuel tank capacity also affect the price. Current offers from Fogo, Altrad Belle and Wacker Neuson in the 5 kW segment (400 V/230 V) can be compared on the individual model pages, where you'll also find exact specifications and the current price.

A 5 kW three-phase generator can power most power tools and small equipment running at the same time on a construction site: drills, angle grinders, lighting, submersible pumps, electric-motor concrete mixers or concrete vibrators with a frequency converter. The combined load of a typical set of 3–4 devices usually falls in the 3–4.5 kW range, leaving headroom up to the 5 kW limit. Heavier loads (welders, larger compressors) often call for a generator from the 10 kW segment instead.

All three brands offer 5 kW three-phase generators with 400 V/230 V output, but they differ in segment: Fogo has the widest range, covering models with AVR stabilization and without it; Altrad Belle focuses on rugged, versatile units built for frequent transport between sites; Wacker Neuson positions itself in the premium segment with higher-grade components. The choice depends on whether the priority is stable voltage for sensitive electronics or a lower purchase cost for simple loads.

A 5 kW three-phase generator works well on a single-family house construction site if three-phase 400 V equipment is running (an electric-motor concrete mixer, a table saw, a compressor) or several 230 V loads at once, spread across 3 phases. For hand tools alone at 230 V, a cheaper single-phase 2–3 kW generator is often enough, so the 5 kW three-phase segment makes sense mainly where the plan includes 400 V equipment or several loads running in parallel.

Petrol or diesel 5 kW three-phase generators typically have a fuel tank of around 15–25 litres, giving roughly 6–10 hours of runtime at 50–75% of rated load. At full 5 kW load, fuel consumption rises and runtime shortens accordingly. Exact tank capacity is listed on the individual model pages.