The following is a recommended voltage drop test limit for use with the test results obtained from the procedure outlined in clause 5.4.3 in CSA Z32. It is important to note that CSA does not endorse this test limit and is provided here as a recommendation by Optum Engineering only.

It can be shown (see derivation of the limit and why 3% is recommended) that the following test result limit may be used to confirm that the voltage drop in a branch circuit (as a percentage of the voltage at the point-of-supply) complies with Item (a) Subrule (1) of Rule 8‑102 in CSA C22.1 with the provision that the voltage drop in the feeder circuit not exceed 2% of the voltage at the point-of-supply: