Code Change Summary: A new code section was added to address pre-energization testing of electrical systems operating over 1000 volts.

Section 110.41 is located in Part III of Article 110 which only applies to installations over 1000 volts. A common application is an industrial facility such as a wastewater treatment plant with 12,470 volt 3-phase switchgear and machinery.

The first part of the new section is about pre-energization testing. If pre-energization testing is required elsewhere in the NEC^®, the complete electrical system design, including settings for protective, switching, and control circuits, must be prepared in advance and then made available if requested by the authority having jurisdiction (AHJ). As well, the system must be tested when first installed on-site. (Factory testing or bench testing is not enough).

The second part of the new code section is about the actual test results and requires the test report to be made available to the AHJ or anyone authorized to install, operate, test, and maintain the system.

One example of a location in the NEC^® that mandates pre-energization testing is 225.56 which addresses outdoor branch circuits and feeders over 1000 volts.

Section 230.95(C) is for testing 1000 amp and larger overcurrent devices equipped with ground-fault protection of equipment (GFPE) for solidly grounded wye electric services of more than 150 volts to ground but not exceeding 1000 volts phase-to-phase. This section is an example of equipment that requires testing in general but the NEC^® does not require the testing to be done before energizing. As well, this GFP testing is for specific overcurrent devices not greater than 1000 volts, therefore new section 110.41 does not apply.

Below is a preview of Article 110. See the actual NEC^® text at NFPA.ORG for the complete code section. Once there, click on their link to free access to the 2017 NEC^® edition of NFPA 70.