Feeder Size Calculator
Conductor and conduit fill sizing tool. For final sizing, verify against the current Canadian Electrical Code.
Inputs
Results
Copper
Aluminum
Checks
Voltage drop check
Copper
Aluminum
Conduit fill summary
Copper
Aluminum
Conduit fill areas (selected conduit type)
Underground: alternate parallel options
Voltage drop calculation – assumptions & method
The voltage drop shown in this tool is an approximate design check intended for preliminary feeder sizing. It is not a substitute for a detailed voltage drop study.
Calculation basis
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- I = total load current
- cosθ = entered power factor (PF)
- sinθ = √(1 − PF²)
- Length = one‑way conductor length
Resistance (R)
- Calculated from conductor cross‑sectional area derived from selected AWG or kcmil size
- Material resistivity based on typical copper or aluminum values at ~75 °C
- For parallel runs, resistance is divided equally among sets
Reactance (X)
- Assumed constant value of 0.08 Ω/km
- Independent of conductor size, spacing, or conduit type
- Divided equally for parallel runs
Additional assumptions
- Skin effect and proximity effect are not explicitly modeled
- Installation‑specific impedance variations are not considered
Design voltage drop vs CEC recommendations
This calculator reports design voltage drop for engineering evaluation. The Canadian Electrical Code provides recommended voltage drop limits (commonly cited as feeders typically ≤ 3%), but these are guidance values rather than absolute limits. Final acceptance should consider equipment tolerances, starting conditions, and project‑specific criteria.
Always verify final conductor sizing and voltage drop against the current Canadian Electrical Code, project specifications, and manufacturer requirements.