Four load categories, each with its own demand factor, combine into a diversified maximum demand that's meaningfully lower than simply adding up connected load.
| Lighting | 40 kW connected, 90% demand factor |
| Socket outlets | 30 kW connected, 70% demand factor |
| HVAC / AC | 60 kW connected, 80% demand factor |
| Motors | 25 kW connected, 75% demand factor |
| Supply | 400 V three-phase, 0.9 power factor |
| Category | Connected load | Demand factor | Demand |
|---|---|---|---|
| Lighting | 40 kW | 90% | 36.0 kW |
| Socket outlets | 30 kW | 70% | 21.0 kW |
| HVAC / AC | 60 kW | 80% | 48.0 kW |
| Motors | 25 kW | 75% | 18.75 kW |
| Check | Requirement | Actual | Status |
|---|---|---|---|
| Diversified maximum demand | n/a (this is the sizing result) | 123.75 kW (79.8% of 155 kW connected) | ✓ PASS |
| Recommended main breaker | n/a (this is the result) | 200 A | ✓ PASS |
Key insight: Demand factors exist because not every category of load runs at its full connected rating simultaneously — sockets in particular (70% here) are heavily diversified since it's unrealistic for every outlet in a building to be drawing rated current at the same instant, while heating loads are often left at 100% because thermostatically-controlled heating genuinely can reach full connected load during cold snaps.
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Open Maximum Demand calculator →These reflect commonly used general engineering practice (typical design values — always confirm against local code or utility rules) for how simultaneously different load categories typically operate at their full connected rating — they are starting points, not fixed universal constants, and a real design should always be checked against the specific project's applicable code, utility requirements, or measured load data where available.
Aggregating multiple boards at a site level applies a further site diversity factor on top of each board's own diversified demand (since not every board peaks at exactly the same moment either), which is exactly what this calculator's advanced multi-board aggregation feature computes — for a single board like this office example, that additional layer of diversity doesn't apply.