Electrical load is governed by one equation: Power (watts) = Voltage × Current (amps), or P = V × I. Rearrange it to find how much you can hang on a circuit before the breaker trips.
What a circuit can take
The supply voltage changes the answer dramatically. A 16A circuit gives you:
- At 230V (Europe) — 230 × 16 ≈ 3680W.
- At 120V (North America) — 120 × 16 ≈ 1920W.
Same breaker, nearly double the wattage at the higher voltage. This is why a US rig needs far more circuits than the same rig in Europe.
Leave headroom & balance the phases
Never load a circuit to 100%. Lamp inrush current at switch-on, heat, and a safety margin mean you aim for around 80% of rated capacity. On a three-phase supply, spread your load evenly across L1, L2 and L3 — dumping everything on one phase overloads it while the others sit idle.
LuminaPlot's power report sums every fixture per circuit and phase, flags overloads, and helps you re-circuit to balance — but the calculator above shows the maths it's doing.
In LuminaPlot 2.0 you can also pin the venue's house power points (socket type, amps, phase), audio tie-lines and network/DMX points on the plot as fixed infrastructure — saved into a venue profile, every new plot in that room inherits them.