Interpretations

Answering questions that may arise related to the meaning of portions of an IEEE standard concerning specific applications.

IEEE Standards Interpretation for IEEE Std 605™-2008 IEEE Guide for Bus Design in Air Insulated Substations

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Interpretations are issued to explain and clarify the intent of a standard and do not constitute an alteration to the original standard. In addition, interpretations are not intended to supply consulting information. Permission is hereby granted to download and print one copy of this document. Individuals seeking permission to reproduce and/or distribute this document in its entirety or portions of this document must contact the IEEE Standards Department for the appropriate license. Use of the information contained in this document is at your own risk.

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October 2011

Interpretation Request #1
Topic:
Bus End Conditions Relevant Clause: 12.1
When a pipe bus conductor passes through a bus support fitting, but is not welded to the fitting (i.e., a "slip fitting"), does IEEE Std 605-2008 consider this to be a pinned, non-moment resisting condition or a fixed, moment resisting condition?

Interpretation Response
IEEE Std 605-2008 defines a pinned end as free to rotate and fixed end is defined as not free to rotate. While we recognize that there is not a 100% true pinned or fixed, IEEE Std 605-2008 leaves it to the design engineer to determine whether to consider the end condition of the pinned or fixed.