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#82507 - 11/19/02 07:10 AM article 300-7 1996 code
mountainman Offline

Registered: 01/29/02
Posts: 54
Loc: Richmond Va. U.S.A.
Article 300-7 of the 1996 code Raceways exposed to different temperatures. Part "b" expansion joints. I rejected the installation because there were no expansion joints in the conduit runs. The enginer replied that article 300-7 does not apply to expansion joints. I do not see how he came up with this conclusion. Can someone enlighten me why part b is under Raceways exposed to different temperatures?

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#82508 - 11/19/02 07:46 AM Re: article 300-7 1996 code
resqcapt19 Offline

Registered: 11/10/00
Posts: 2209
Loc: IL
Yes, the section does require expansion joints, but only where necessary to compensate for thermal expansion and contraction. Just because the raceway is exposed to different temperatures does not mean an expansion joint is required. You have to do a calculation based on the range of temperatures and the coefficient of expansion to determine if an expansion joint is necessary.


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