ECN Forum Forums General Topics of the Trade General Discussion Area opinions on project

Ayrton:

Sounds like a plan.....
"I am though, considering getting an electrical engineer involved just for the liability.

The life Safety is something I had not considered. THanks for bringing it up."

You can not use the 90 degree column unless the lugs AND equipment are rated 90 degrees and unless I'm mistaken there's no service equipment or transformers rated as such.

You can use the 90 degree column for derating though.

I agree. The 90 degree column is the wrong place to look for your ampacity, but it's a very common mistake.

You are limited by the temperature ratings of the lugs at the ends of the cable (see 110.14C). In every installation that I have ever seen or done you ended up being limited to the 75 degree column for the ampacity.

350 kcmil THHN is 310 Amps.
8 sets gets you 2,480 Amps.
Since the overall ampacity is greater than 800 Amps, you can't get any relief from 240.4C.

Is that an adjustable MAIN?

In which case you could lower it to 2,480 Amps and the hotel would never know the difference.