I think most people dont really know much about insulation resistance and with all the myths around it gets confusing, I think this simple statement made by BICC who know a little bit about cables sums it up for electrical contractors.
The purpose of the IR test is to check for damaged insulation, this can be mechanical damage or damage by heat, (overloaded cables), readings less than 2 Mohm indicate damaged insulation, readings of 2-50 Mohm are indicative of long circuit lengths, moisture and contamination and do not indicate the insulation quality, therefore readings of 2-50 Mohm should not be specified as a fail value.
I think most people dont really know much about insulation resistance and with all the myths around it gets confusing, I think this simple statement made by BICC who know a little bit about cables sums it up for electrical contractors.
The purpose of the IR test is to check for damaged insulation, this can be mechanical damage or damage by heat, (overloaded cables), readings less than 2 Mohm indicate damaged insulation, readings of 2-50 Mohm are indicative of long circuit lengths, moisture and contamination and do not indicate the insulation quality, therefore readings of 2-50 Mohm should not be specified as a fail value.
