Limitations of Hottest-Sport Temperature Rise Over Outside Average Ambient
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Part of Metal-Enclosed Bus
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Limit of Hottest Spot Temperature Rise, Degrees C
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Limit of Hottest Spot Total Temperature, Degrees C
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Bus conductor (plain connection joints)
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30
|
70
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Bus conductor (connection joints silver surfaced or equivalent and bolted or welded)
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50 or 65 unless limited by insulation
|
90 or 105
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Enclosure and support structures where easily accessible
|
40
|
80
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Enclosure and support structures where inaccessible
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70
|
110
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Insulation
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As limited by material classification
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N/A
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Terminations-machine, transformer, etc.
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Same as bus conductor (except as modified by equipment bushing)
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N/A
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