JJBDCB had written this in response to
http://www.thestuccocompany.com/cons...ion-11813-.htm
:
Dennis i dont where u get your info but NEC is a private company white is
neutral on 110 in the USA , i take it your not a elecrtian. whit is not
just considered just identified conductor !!!!
World Region, country
or other entity(ies) Live Neutral Protective earth/ground
EU, Australia & South Africa (IEC 60446) brown blue green & yellow
Australia & New Zealand (AS/NZS 3000:2007 3.8.1) brown light blue
green/yellow
United States and Canada black (brass) white (silver) green (green)
Standard wire colours for fixed cable
(In or behind the wall wiring cables)
Region Live Neutral Protective earth/ground
EU (IEC 60446) including UK from 31 March 2004 brown blue green & yellow
Australia and South Africa red black green & yellow (core is usually bare
and should be sleeved at terminations. In Australia the earth core has
been separately insulated with green or green/yellow plastic since about
1980.
United States and Canada black, red, blue(brass) white (silver) green
(green)
or bare copper wire
Note: the colours in this table represent the most common and preferred
standard colours for single phase wiring however others may be in use,
especially in older installations.
Since 1897 the U.S. National Fire Protection Association, a private
nonprofit association formed by insurance companies, has published the
National Electrical Code (NEC). States, counties or cities often include
the NEC in their local building codes by reference along with local
differences. The NEC is modified every three years
JJB
-------------------------------------
Dennis wrote:
Neutral wires are present in 120V circuits as well, yes neutral and
ground
busses are bonded together in the panel, but the white wire is
still
called neutral though it carries the full return current. A white
wire can
be hot if used in a switch drop or to a 240v appliance receptacle
but in
that case there should be a band of black or red tape around it to
mark it
as such, though in most houses I've worked on they've skipped
that.
A lot of people refer to the white as a neutral, but offically in the
NEC is
referred to as an "identified" conductor.
A neutral is only present in a 240 v or higher branch circuit or
feeder. (I
think that's where a lot of confusion comes in as the potential between
a
240 volt leg and the neutral is 120 volts, however that's not a branch
circuit in and of itself). Because a neutral carries only an
unbalanced
load, it's allowed to be reduced in size from the ungrounded phase
conductors. See 220.61 where the NEC talks about how to calculate the
unbalanced load on a neutral. A grounded white wire in a 120 volt
circuit
always carries the full load of the circuit and is sized the same as an
ungrounded conductor.
I pulled this off of Mike Holt's website (read carefully, the 2-wire
circuit
in the 2nd para is a standard 120 volt circuit):
Neutral Conductor. The IEEE dictionary defines a neutral conductor as
the
conductor with an equal potential difference between it and
the other output conductors of a 3- or 4-wire system. Therefore, a
neutral
conductor is the white/gray wire of a 3-wire single-phase
120/240V system, or of a 4-wire three-phase 120/208V or 277/480V
system.
Since a neutral conductor must have equal potential between it and all
ungrounded conductors in a 3- or 4-wire system, the white wire
of a 2-wire circuit, and the white wire from a 4-wire three-phase
120/240V
delta-connected system are not neutral conductors-they're
grounded conductors.
Anyway, I believe that the white IS called a neutral in the UK, but not
here
in the US (not by the NEC anyways).
##-----------------------------------------------##
Delivered via
http://www.thestuccocompany.com/
Building Construction and Maintenance Forum
Web and RSS access to your favorite newsgroup -
alt.home.repair,alt.building.construction,sci.elec tronics.repair - messages and counting!
##-----------------------------------------------##