310.15(B)(18) and terminations

[dm9289]

I work in a situation that has many hot areas and I am confused about the usage of type Z cable and other higher temp cables.

For many situations like use of THHN you would use the 90c ampacity value then derate due to temp or number of conductors, but the ampacity the wire is used at cannot exceed that of the termination for example in some instances the 60c rating would be max and some instances 75c.

For the use of TYPE Z is there any equipment rated at and with terminals/connectors that can be used at 150C rating?

If you do not use the 150C rating in these situations what table or temps do you use?

Or is this a situation that requires special connectors rated at 150c and a splice block before the device to transition to say THHN?

 

[W@ttson]

So I had the SAME question when I looked at table 310.15(B)(18). There are tons of posts on this site that talk exactly about what you mention about the terminal rating even when using High Temp cable. So like you say, if there is a table that gives you the rating at the temperature of the insulation, what use is it unless the terminals are some special High temperature terminals?

The only way I see it possible to use the values of 310.15(B)(18) is if you use high temperature terminal blocks like these ceramic ones:

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