National Electrical Installation Standards

Standards as High as Your Own

Thursday, September 22, 2022



I’m an apprentice and am looking for some insight. We are removing STCs that are rated for 2000 amps and upgrading to STCs rated for 2500 amps. There are seven units total. Six have been installed. Bus bars line up. Everything was going fine until the seventh unit. The bus bars are 1/4” to 1/2” off from the bus bars in the other six units. We have been told to “just bend them” as well as “break the seals from the torqued bolts”. Besides voiding the warranty and a failure to apply 110.12, could there be other code violations for this problem?

Best wishes,

Robert Spitzer



Robert, it is always nice to see an apprentice interested in the NEC™️ and even nicer to see an apprentice citing Section 110.12 on Mechanical Execution of Work and Workmanship. It is safe to say that "bending the busbar" and "breaking factory seals" is not workmanlike. Those type of modifications may also impact the manufacturer's warranty, and even more important the equipment listing. Section 110.2 requires equipment to be approved by the electrical inspection authority. The listing of equipment as found in Section 110.3, is a common method of establishing suitability. Many inspection authorities rely on the listing as part of their approval. If the modifications mentioned, violate the listing, the inspector may require a field evaluation to re-establish the suitability of the equipment. 

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