Free — no sign-up. CEC mode pre-selected.
Canadian electrical installations follow the Canadian Electrical Code (CEC), Part I, CSA C22.1-2024 for voltage drop — not the NEC. Rule 8-102 of the CEC sets the permissible voltage drop limits: no more than 3% on any branch circuit and no more than 5% combined from the point of service to the final utilization equipment. These limits mirror the NEC's informational notes in 210.19(A) and 215.2(A)(1) in spirit, but they appear as mandatory requirements in the CEC rather than advisory notes. That is a critical difference: in Canada, exceeding the 3%/5% limits is a Code violation; in the US, the NEC voltage drop figures are recommendations that the inspector may or may not enforce depending on the AHJ.
The calculation method is also slightly different. The CEC uses a resistance-based formula derived from conductor resistances published in Table 2 (wire ampacity and resistance data), while the NEC voltage drop formula often uses the circular-mil constant K (12.9 for copper, 21.2 for aluminum). Both approaches yield the same result when the same conductor resistance values are used, but the CEC table-based method is the authoritative approach for Canadian permit submissions.
SparkShift's voltage drop calculator handles both NEC and CEC modes. When you select the CEC toggle, the calculator: - Applies the 3% branch / 5% combined limits as pass/fail thresholds (not informational notes) - References CEC Rule 8-102 in the results panel - Cites CEC Table 2 for conductor resistance values - Formats the output for Canadian permit submittal
Common CEC voltage drop scenarios include service feeds to dwellings in rural British Columbia or Alberta (long distances from the utility transformer), commercial feeder design in Ontario under the OESC 2021, and EV charger circuit sizing under CEC Rule 8-106 where the combined voltage drop limit still applies to the EVSE branch circuit.
For arc flash, motor, and transformer calculations under the CEC, always verify which provincial edition applies — Ontario uses the OESC (based on CEC 2021), while BC and Alberta have adopted CEC 2021 with provincial amendments.
SparkShift pre-selects CEC mode. Results cite CEC rules (8-102) for permit documentation.
Open CEC voltage drop calculator →Each Canadian province and territory has adopted a version of the CEC. Verify the adopted edition and local amendments with your AHJ.
CEC Rule 8-102 requires that voltage drop not exceed 3% on any branch circuit and not exceed 5% combined from the point of service to the utilization equipment. These are mandatory limits in the CEC, not advisory notes as in the NEC.
The limits are numerically similar (3%/5%), but the CEC makes them Code requirements while the NEC treats them as informational notes. The CEC also references conductor resistance values from CEC Table 2 rather than the K-constant method common in NEC practice.
All provinces and territories that have adopted a version of the CEC (CSA C22.1) are subject to Rule 8-102. Ontario (OESC), British Columbia, Alberta, and all other provinces apply this rule. Check the provincial adopted edition — most are on CEC 2021 as of 2026.
Yes. EV charger (EVSE) branch circuits under CEC Rule 8-106 are still subject to the 3% branch circuit voltage drop limit. This is especially important for longer runs from the panel to the garage or outdoor EVSE location.
Disclaimer: SparkShift calculators are provided for informational purposes. Always verify calculations against the adopted CEC edition in your province and confirm requirements with your local authority having jurisdiction (AHJ) before commencing work. The CEC edition adopted may differ by province — Ontario uses the OESC, BC uses the BC Electrical Safety Regulation, and other provinces have their own adopted editions.