On Sat, 11 Jul 2020 16:08:28 -0700 (PDT),
wrote:

wrote:
On Thu, 9 Jul 2020 15:38:42 -0700 (PDT), wrote:
On Wednesday, July 8, 2020 11:27PM, Ed Pawlowski wrote:
On 7/8/2020 10:26 PM, Jim Joyce wrote:
On Wed, 08 Jul 2020 21:01:22 -0400, wrote:

On Wed, 08 Jul 2020 13:45:10 -0500, Jim Joyce
wrote:

On Tue, 07 Jul 2020 19:58:37 -0400, wrote:

On Tue, 7 Jul 2020 12:56:29 -0700 (PDT), wrote:

On Monday, July 6, 2020 at 11:14PM, "Scott Lurndal" wrote:
writes:
Wiring up switch w/pilot light...

When wiring up a switch that requires another wire back from the load to attach to the switch to power the pilot-light (illuminated when ON).
Do I have to use #14 wire ?


Use the appropriate AWG for the breaker and length of run. On a 15A circuit, AWG14 is
the minimum AWG, it could be AWG12 for a long run. If the circuit is protected by a
20A breaker, AGW12 is the smallest size you can use.

Pretty much all new construction is going to use 12 gauge hot with maybe even 10 wire for a neutral.

Huh?
You must not see much actual construction.
In 1 & 2 family, 14-2 is alive and well for general lighting circuits.
#12 is only used for kitchens, laundries and bathrooms.

In my housing development, there isn't an inch of 14ga anywhere. All of the
120v circuit breakers are 20a and all of the Romex is yellow, no exceptions
for lighting circuits.

On the surface that might sound good but you usually end up with fewer
circuits. The breakers are sized by square footage, not the number of
outlets.

Yeah, I don't think it's a good thing. For example, the entire M-I-L suite
is served by a single 20a breaker. That part of the house includes a living
room, a bedroom, a walk-in closet, and a bathroom, all with lights and
receptacles throughout. It's basically an apartment inside the house, and
the whole thing is served by a single breaker.


Ouch! Was that wired by a pro? Lights and receptacles on the same
breaker?

Believe it or not, some residential slash commercial establishments have a high-leg conductor from a 120/240V 3 phase where an exit sign and an outlet (and flood light?) can be attached to 277v lighting (for emergency reasons).

Huh?

I was listening to someone explain why a conductor from the 277 orange b phase from the ceiling went to an exit sign and an outlet that the maintenance man would know to use in an emergency.

The high leg on a 240/120v center tapped delta is 208v.
You get 277 from 480v wye. (L/N)

You are still not getting 277 from a center tapped 240/120 delta.

I saw this online awhile ago: "If you DO read 277V Phase to Ground at some point down stream, that does NOT automatically mean it is Wye secondary. There are a myriad of reasons why your meter may read 277V on an ungrounded Delta system. -Jul 11, 2017

Ungrounded systems are exceedingly rare and come with a whole lot of
extra precautions. Generally it will only be supplied to a factory
with some extremely critical process and it would only serve that
process. There will be a grounded service for everything else.
Glass plants are one example I have heard about. If that process stops
with glass in the pipe, you will be rebuilding the plant.