On Mon, 28 Sep 2015 05:41:27 -0700, Don Y
wrote:

On 9/28/2015 5:34 AM, wrote:
On Sun, 27 Sep 2015 20:11:09 -0700, Don Y
wrote:

On 9/27/2015 7:09 PM, wrote:
On Sun, 27 Sep 2015 18:31:43 -0700 (PDT), wrote:

Hi. I'm laying out my basement lighting. I expect to have 25 recessed lights, each is 75watt max rating (even though I will use LED, I know I must still assume max rating of fixture). 25x75=1875watts/120V = 15.6amps.
So, I cannot use one 15amp breaker and 14awg wire.
Can I wire all the lights with 12awg and a 20amp breaker?
All comments appreciated.

Thanks
Theodore
No. You are limited to the number of "devices" on the circuit
Generally accepted as 8 on 15 amp and 12 on 20 IIRC.. I'd wire it on 2
circuits, with either 2 rings, or rows, or every second lamp on
opposite circuits.
I'd use an edison circuit,or at least a double (120/240) breaker
powering a 2 pole contactor controlled by a single switch if you want
all lights on at once all the time. I have an application where 3
circuits are controlled by a 3 pole (3 phase) contactor controlling 3
circuits of lighting on one switch - 12 potlights per circuit, 20 amp
breakers. Originally 75 watt incandescents, currently running 9 watt
LEDs.

That applies to *outlets* (180VA per single/dual), not circuits that are
used exclusively for hardwired lighting devices.

As long as he doesn't tack on "one" convenience outlet he might get
away with it. Local interpretations vary.

This is the problem ^^^^^^^^^^^^^^^^^^^^^ In most areas, there is no
way to appeal an inspector's ruling. So, if inspector misinterprets the
Code (or, is "having a bad day"), you're stuck with his ruling.


That is not really true but if the boss (AHJ) agrees you are stuck.
In Florida the AHJ is the state, not the local BO. There are no "local
codes".
Just be sure you are right before you go through that process.
At the end of the day, it may come down to what plan review said about
your plans. Not "built to plan" is a slam dunk for the inspector..

OTOH in residential there is no 180va rule on receptacles and you
would win that fight if some inspector tried to enforce it..I have
never seen one try. It is a basic concept in residential load
calculations that you do it by square footage, not receptacle count.
The receptacle placement requirements pretty much assure you will have
plenty you never use.