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Canada — CEC Rule 8-102

Canada uses the same AWG sizes and 120/240 V split-phase service as the US — but the Canadian Electrical Code makes the limits mandatory: Rule 8-102 caps drop at 3% for a feeder or branch circuit and 5% from supply to point of utilization. Same math as the NEC, none of the 'informational note' ambiguity.

Voltage Drop
Find Wire Size
Max Length
Advanced — units, power factor, parallel sets, energy cost
PASS
Voltage Drop
Percent Drop
Voltage at Load
Power Lost
Wire Resistance
Ampacity 75°C
0%3% branch5% total8%+

What changes at the border

Physics and conductor data are identical — Table 8-style resistance, AWG, the ×2 round trip. The legal status flips: under CEC 8-102 an inspector can fail an installation on voltage drop alone, so Canadian work designs to 3%/5% as hard ceilings, with calculated demand current as the basis. Cold climate adds a practical wrinkle: long runs to detached garages and block-heater circuits are routine, and the EV charger and garage feeder presets apply unchanged.

Frequently Asked Questions

Is voltage drop enforceable in Canada?

Yes — CEC Rule 8-102 is a requirement, not a note. 3% maximum for a feeder or branch circuit, 5% total from supply service box to the point of utilization.

Can I use this site's NEC data for CEC work?

The conductor resistance and ampacity tables are effectively common; verify ampacity details against CEC Table 2 for your installation condition, and treat every drop result here against the mandatory 3%/5%.

Built & maintained by Murugan Vellaichamy · Every calculation verified against NEC Chapter 9 Table 8 & Table 310.16 published values · Informational reference — not engineering advice