was is the allowable ampacities for 18 awg thhn
Not allowed for General use, they are allowed for Fire Alarm systems (and a few other exceptions), the ampacity given in 760-23 is 7 amperes, and 6 amperes (from table 402-5) from 760-27
Table 402.5 list 18 AWG at 6 amps, but as George said, 18 AWG is very limitted in its use.
THHN is not listed as a fizxture wire, but TFN and TFFN seem to have similiar characteristics.
What is this being used for?
this was the question my foreman gave me. So i looked it up but was using table 310.15 and was confused, so i decided to ask you guys
It is listed as 14 amps @ 90 C in 310.16.
Now what can I conect it to that is rated 90 C?
310.16 shows no rating for 18 AWG @ 75 or 60 C.