Site power no longer means a diesel set by default. Once you know connected load, simultaneity and shift length, a large share of the loads can run from storage — keeping a generator only for the remainder.
Three numbers decide, not gut feeling
Count the loads that run at the same time — not everything standing on site. Simultaneity is the most common sizing error, and it usually lowers the required power considerably.
Read the input rating from every rating plate and add them up. Not the figure in the brochure, but what the tool actually draws.
Add 20 to 30 percent reserve. Motors, compressors and welding sets draw a multiple of their rated current when starting.
Check whether any load requires 400 V three-phase. If so, that decides the configuration — not the size of the generator.
What storage carries — and what it does not
Lighting, hand tools, extraction, chargers and electronics: the standard base of a site, which storage covers without limitation.
Welding sets and compressors: feasible, but the starting current must be covered. This is where one unit often becomes two in parallel.
Dewatering across days, winter heating, continuous operation: the case where a generator still makes sense — or a combination of both.
P-series parallel power systems
One modular platform. Add parallel units where the load grows — two or three units single-phase, or three units for 400 V three-phase.
Configuration
Units
Rated power
Usable capacity
Weight
Output
P25
1
2,500 W
2.7 kWh
29 kg
230 V / 16 A · single-phase
P25 + P25-D
2
5,000 W
5.4 kWh
≈60 kg
230 V · single-phase · AC230V/20A output
P25 + P25-D
3
7,500 W
8.1 kWh
≈90 kg
230 V · single-phase · AC230V/30A output
P25 + P25-T
3
7,500 W
8.1 kWh
≈90 kg
400 V · three-phase · AC400V/10A output
P25
Units
1
Rated power
2,500 W
Usable capacity
2.7 kWh
Weight
29 kg
Output
230 V / 16 A · single-phase
P25 + P25-D
Units
2
Rated power
5,000 W
Usable capacity
5.4 kWh
Weight
≈60 kg
Output
230 V · single-phase · AC230V/20A output
P25 + P25-D
Units
3
Rated power
7,500 W
Usable capacity
8.1 kWh
Weight
≈90 kg
Output
230 V · single-phase · AC230V/30A output
P25 + P25-T
Units
3
Rated power
7,500 W
Usable capacity
8.1 kWh
Weight
≈90 kg
Output
400 V · three-phase · AC400V/10A output
Wiring
The parallel distribution unit carries one power input and one data input per battery unit, and a single output to the load.
AC230V/20ATwo P25 units, 230 V single-phase.
AC230V/30AThree P25 units, 230 V single-phase.
AC400V/10AThree 230 V P25 units in parallel make 400 V three-phase — all three required, or the system loses a phase.
How the parallel link is wired
Each P25 runs one power cable and one data cable to its own input pair on the distribution unit.
The distribution unit has three input pairs (L1 / L2 / L3); one pair per battery unit.
Only the distribution unit output feeds the load. Battery units are never connected to the load directly.
Each unit keeps its own protective device; no unit back-feeds another.
Three configurations, one platform
Start with a single unit and add parallel units only when the load demands it. Every configuration runs the same battery unit and the same distribution unit.
P25
The core unit. A fanless, self-cooling 230 V power station that replaces the combustion generator on site — no exhaust, no idling noise, no fuel run.
Two or three units linked through the parallel distribution unit for 230 V single-phase loads. Power and capacity stack — start with two, add a third when the job needs it.
Three 230 V P25 units in parallel produce the 400 V three-phase supply that runs tools which will not start on single phase. All three are required — remove one and the system loses a phase. Carried and assembled by hand: no crane, no lifting gear.
Technical data, conformity and transport conditions are in the data sheet. Three details are enough for a sizing: the load list, the voltage, and how long the system must run without recharging.
The questions buyers actually ask before a first order — answered with numbers from our own datasheets, not from a brochure.
Does one storage unit cover a whole site?
For lighting, hand tools, extraction and chargers usually yes. What decides is simultaneity: count what actually runs in parallel and add the input ratings — not the number of tools standing on site.
What about continuous load over days, such as dewatering?
Storage alone is not intended for that. Calculate the daily energy demand and the recharging option; if the two do not match, a generator or a combination remains the right choice.
Why plan 20 to 30 percent reserve?
Because motors, compressors and welding sets draw a multiple of their rated current when starting. Without reserve the system trips exactly at start-up — the most common reason for the feedback that a unit is too weak.
Can I expand later instead of buying bigger?
Yes, through parallel operation. A second unit is added instead of replacing the first; for rental that is the cheaper strategy because the base equipment stays in the fleet.