National Electrical Installation Standards

Standards as High as Your Own

Tuesday, May 29, 2018


Re: CQD answer published Thursday, May 3, 2018 -Service Calculations

1) Actually, I believe the electrical contractor is responsible for the design and load calculations of the electrical system. The inspectors role is to review, inspect and verify the work is compliant to adopted code edition. If the inspector is involved on an existing system, pending contractors submittal, he may offer recommendations of upgrade; but he is not the designer or professional to design or it set forth the specs. That should be the role of contractors and/ or design professionals in consultation with the client's needs. RE Miller

2) Thanks for the service you provide. This is in response to question Jeff posed on 02/05. The inspectors rarely look at the required calculations. They are there to look at the physical installation. The review of the technical/design details is done by the people that review the plans and issue the permits. Unless it is a small jurisdiction, these tasks are seldom accomplished by one individual. Keep up the good work. Mike, Columbus, OH



Hey RE and Mike thanks for your comments and kind words. You are correct, the calculations are the contractor, designer, engineer, etc. responsibility, not the AHJ's. Plans review is not a requirement in all locations. The original question seemed to infer that it was apparent or obvious the service was not sufficiently sized for the load. In that case the AHJ can ask to see the calculations.

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