I know when determining ampacity of cables you use the 75deg column of table 310.16 for conducters rated 0-2000V. But what about when a special cable is used such as a mining or marine cable and the manufacturer provides a specific ampacity table for that particular cable that has higher values then those listed in 310.16? Can these higher ampacity values be used for calculations and sizing required by the NEC?
Ampacity of special cables
- Thread starter Pitt123
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Its not likely you can use that value and it is even a question as to the use of that cable for an NEC installation.
Most of the time they give you the 90?C ampacity in free air. There are very very few NEC applications where you can use that rating. You have to use the rating found in the NEC for the type of cable you are using. If there is no rating in the NEC, you can't use the cable at any ampacity.
Most of the time they give you the 90?C ampacity in free air. There are very very few NEC applications where you can use that rating. You have to use the rating found in the NEC for the type of cable you are using. If there is no rating in the NEC, you can't use the cable at any ampacity.
weressl
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Unless 310.15(C) and/or the use conductors that are not listed in the NFPA 70 is cleared with the AHJ. Although it is unclear to me what "under engineering supervision" means.
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