If you genuinely can't tell where a lighting circuit ends (due to the way in which it has been wired) I presume you would test for R1+R2 and Zs at every point and then record the highest reading?
Continuity test on the cpc at every point from the CU, the highest reading will be the farthest point of the circuit. Make sure the switches are all on.
Reply to R1+R2 and Zs - Don't know where the light circuit ends! in the Periodic Inspection Reporting & Certification area at ElectriciansForums.net
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