HIDDEN — ELECTRICAL LOAD CALCULATOR
Home & apartment load — single-phase 230 V / three-phase 400 V · breaker & cable sizing
System
Diversity < 1.0 if not all loads run at once. Length is used for voltage-drop estimate.
Loads
Apply to all:
Set qty =
Scale watts ×
| Description | Watts each | Qty | Type | Total W |
|---|
Tip: AC units, fridges, pumps and washing machines are motor loads — the tool adds a start-surge margin for them. Use the demand factor (below 1.0) because a home never runs every appliance at once.
Totals
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Total connected watts
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Total connected kW
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Total connected amps
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After diversity (kW)
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After diversity (amps)
“Connected” = everything switched on at once (worst case). “After diversity” = realistic demand using your diversity factor — this is what the breaker & cable are sized on.
Results
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Total load (after diversity)
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Design current per phase
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Suggested breaker
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Suggested cable (Cu)
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Voltage drop
Quick presets — load a whole home
Full plan — main load & DB schedule
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Main connected load
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Main current
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Main breaker
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Main incomer cable
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Outgoing circuits
Each load line becomes one outgoing way from the DB, sized on its own (230 V circuit, 1.25× continuous). Main incomer sized on total after diversity. Distribute single-phase circuits evenly across L1/L2/L3 on three-phase supplies.
Live line — current passing
Animation speed & colour follow the calculated load vs breaker rating. Green <70%, amber 70–90%, red >90% of breaker.
Socket & ring circuit planner
Cable reference — all sizes (Cu)
| Cable mm² | Ampacity (A) | Max MCB | Max length @3% drop |
|---|
Ampacity is a conservative guide for Cu in conduit ~30 °C. Max length is for the current design current shown in Results, at 3% voltage drop. Derate for grouping, high ambient temperature, and insulation type per local regs.