pauluk

Over here in Britain it's kind of an unwritten convention to start with the high-power circuits next to the main and then gradually work down the bus ending with the 5 or 6A lighting circuits at the far end.

That is the 'normal' way here as well. I am just not sure it makes a bit of difference.


ShockMe77

I want to start takings pics of my work but the fella's at work all think I'm a bit off my rocker for wanting to do that.

Yeah that happens, so what? [Linked Image]

The one thing I don't understand is this, why do the conductors coming through the "donuts" (in pic #3) have to be derated? What article prohibits this? I looked at 310.15 (B)(2)(A).

In the right hand 1" EMT are 12 current carrying conductors.

Table 310.15(B)(2)(a) requires a 50% derate for 12 current carrying conductors.

Table 310.16 shows 12 THHN as 30 amp rated.

30 * .5 = 15 amps

Code wise the breakers should be 15 amp.

By the way MA uses different de-rating tables so this is a legal install in MA. [Linked Image]

Tiger

Grade A Bob

Thanks Dave I take you to be a guy with high expectations so that is high praise.

Bob

Bob Badger
Construction & Maintenance Electrician
Massachusetts