The table value for ampacity from 310.16 has limited application. Here are the conditions which must be present for the table ampacity to be correct.
1. The temperature along the entire length of the conductor can not be greater than 86 degrees Fahrenheit.
2. The conductor can not serve a continuous load at the table ampacity.
3. The conductor can not be in a raceway with more than a total of three conductors.
4. The conductor can not be terminated in a lug with a temperature rating of less than its own temperature rating.
Here are some straight look-ups for table ampacity. Listen to the audio support for instructions.
Find practice problems HERE.
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