I am wondering how the code views this. I was just wiring my barn and
ran out of 12-2 romex. Rather than buy more, I decided to just use
14-2 since I had 200 feet of it. This 14-2 is only going to one
light, one of those porcelin fixtures that are rated at 100W.

As far as safety, I am not worried in the least. It's only going to
run one 100W bulb (or less). As far as being inspected, I am also not
worried. In barns and sheds they really dont care, unless there are
bare wires or some obvious danger source. I'm just curious how the
code views that? For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

In my case, I have one center light fed by #12, and one light on the
left another on the right. Each of those lights are fed off the
center light with about 16 feet of #14.

Thanks

Mark

wrote in message
...
I am wondering how the code views this. I was just wiring my barn and
ran out of 12-2 romex. Rather than buy more, I decided to just use
14-2 since I had 200 feet of it. This 14-2 is only going to one
light, one of those porcelin fixtures that are rated at 100W.

As far as safety, I am not worried in the least. It's only going to
run one 100W bulb (or less). As far as being inspected, I am also not
worried. In barns and sheds they really dont care, unless there are
bare wires or some obvious danger source. I'm just curious how the
code views that? For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

In my case, I have one center light fed by #12, and one light on the
left another on the right. Each of those lights are fed off the
center light with about 16 feet of #14.

The problem, as the NEC sees it is two fold. If somehow the light started
drawing too much current, the breaker would not protect the wiring. Or, if
that seems too farfetched, someone after you might change the light without
realizing the wire is inadequate.

wrote:
I am wondering how the code views this. I was just wiring my barn and
ran out of 12-2 romex. Rather than buy more, I decided to just use
14-2 since I had 200 feet of it. This 14-2 is only going to one
light, one of those porcelin fixtures that are rated at 100W.

As far as safety, I am not worried in the least. It's only going to
run one 100W bulb (or less). As far as being inspected, I am also not
worried. In barns and sheds they really dont care, unless there are
bare wires or some obvious danger source. I'm just curious how the
code views that? ...
In my case, I have one center light fed by #12, and one light on the
left another on the right. Each of those lights are fed off the
center light with about 16 feet of #14.

If you don't care, why ask?

By code, it's not up to snuff, because code is designed to protect the
fixed wiring, not the fixtures or other end load. I agree it's not an
inherent safety hazard as described as long as the use remains as is.

I would be somewhat suprised if an inspection (assuming you're in a
place where zoning applies and it will be inspected) didn't point it
out as a deficiency, but that would be dependent on, as you say, what
your local inspector's penchant/foibles is/are...

Of course, you can easily alleviate the issue by putting a 15A breaker
in the panel for that lighting circuit and be over-sized rather than
under-sized in a portion of the circuit.

Me being me, I'd probably have just got another roll of 12 and finished
it out simply for the self-aesthetics of the job and knowing that
eventually I'd use that roll for other stuff around the place, but
again, that's just me having had to grow up under my grandpa and dad...

OH, but that would have cost $8.

--
Steve Barker


"dpb" wrote in message
ups.com...
wrote:

Me being me, I'd probably have just got another roll of 12 and finished
it out simply for the self-aesthetics of the job and knowing that
eventually I'd use that roll for other stuff around the place, but
again, that's just me having had to grow up under my grandpa and dad...

Hummm... I just figured out why there are so many barn fires in which
insurance companies refuse to pay for damages!


wrote in message
I am wondering how the code views this. I was just wiring my barn and
ran out of 12-2 romex. Rather than buy more, I decided to just use
14-2 since I had 200 feet of it. This 14-2 is only going to one
light, one of those porcelin fixtures that are rated at 100W.

As far as safety, I am not worried in the least. It's only going to
run one 100W bulb (or less). As far as being inspected, I am also not
worried. In barns and sheds they really dont care, unless there are
bare wires or some obvious danger source. I'm just curious how the
code views that? For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

In my case, I have one center light fed by #12, and one light on the
left another on the right. Each of those lights are fed off the
center light with about 16 feet of #14.

Thanks

Mark

In article , wrote:

I'm just curious how the
code views that?

As a violation.

For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

Fixture wires generally have a much higher temperature rating than supply
wires, which enables them to carry higher current on smaller wires.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

On Mon, 11 Dec 2006 15:50:26 GMT, "Toller" wrote:


wrote in message
.. .
I am wondering how the code views this. I was just wiring my barn and
ran out of 12-2 romex. Rather than buy more, I decided to just use
14-2 since I had 200 feet of it. This 14-2 is only going to one
light, one of those porcelin fixtures that are rated at 100W.

As far as safety, I am not worried in the least. It's only going to
run one 100W bulb (or less). As far as being inspected, I am also not
worried. In barns and sheds they really dont care, unless there are
bare wires or some obvious danger source. I'm just curious how the
code views that? For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

In my case, I have one center light fed by #12, and one light on the
left another on the right. Each of those lights are fed off the
center light with about 16 feet of #14.

The problem, as the NEC sees it is two fold. If somehow the light started
drawing too much current, the breaker would not protect the wiring. Or, if
that seems too farfetched, someone after you might change the light without
realizing the wire is inadequate.


Back when they still used knob and tube, you'd just
stick a ceramic fixture with a 15A fuse in it
between the heavy wiring and the lighter wiring.

Do they still make things like that, or is it
a full-blown sub-panel or nothing?

--Goedjn

On Mon, 11 Dec 2006 10:53:59 -0600, "Steve Barker LT"
wrote:

OH, but that would have cost $8.

Where can you buy 50 feet of 12-2 for $8. Please tell me. I'll but
100 rolls immediately.

In article . com, dpb wrote:
wrote:
I am wondering how the code views this. I was just wiring my barn and
ran out of 12-2 romex. Rather than buy more, I decided to just use
14-2 since I had 200 feet of it. This 14-2 is only going to one
light, one of those porcelin fixtures that are rated at 100W.

As far as safety, I am not worried in the least. It's only going to
run one 100W bulb (or less). As far as being inspected, I am also not
worried. In barns and sheds they really dont care, unless there are
bare wires or some obvious danger source. I'm just curious how the
code views that? ...
In my case, I have one center light fed by #12, and one light on the
left another on the right. Each of those lights are fed off the
center light with about 16 feet of #14.

If you don't care, why ask?

By code, it's not up to snuff, because code is designed to protect the
fixed wiring, not the fixtures or other end load. I agree it's not an
inherent safety hazard as described as long as the use remains as is.

I would be somewhat suprised if an inspection (assuming you're in a
place where zoning applies and it will be inspected) didn't point it
out as a deficiency, but that would be dependent on, as you say, what
your local inspector's penchant/foibles is/are...

Of course, you can easily alleviate the issue by putting a 15A breaker
in the panel for that lighting circuit and be over-sized rather than
under-sized in a portion of the circuit.

Me being me, I'd probably have just got another roll of 12 and finished
it out simply for the self-aesthetics of the job and knowing that
eventually I'd use that roll for other stuff around the place, but
again, that's just me having had to grow up under my grandpa and dad...


http://www.ci.longmont.co.us/bldgins...ial/wiring.htm

Code actually requires all wiring in a branch circuit to be of the same
size. However, I cannot guarantee that this item is in the NEC as opposed
to being merely in a local building code. I am under the impression that
at least most items in that page are actually specified by NEC.

- Don Klipstein )

In , Doug Miller wrote:
In ,marad :

I'm just curious how the code views that?

As a violation.

For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

Fixture wires generally have a much higher temperature rating than supply
wires, which enables them to carry higher current on smaller wires.

Since resistance increases with temperature, actual ampacity does not
increase much with an increase in temperature rating. And ampacity
according to the code does not increase at all.

- Don Klipstein )

In article , (Don Klipstein) wrote:

http://www.ci.longmont.co.us/bldgins...ial/wiring.htm

Code actually requires all wiring in a branch circuit to be of the same
size. However, I cannot guarantee that this item is in the NEC as opposed
to being merely in a local building code. I am under the impression that
at least most items in that page are actually specified by NEC.

Must be a local code. The NEC specifies minimum requirements for conductor
sizes, but has no requirement I'm aware of that all conductors on a circuit be
the same size.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

In article , (Don Klipstein) wrote:
In , Doug Miller wrote:
In ,marad :

I'm just curious how the code views that?

As a violation.

For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

Fixture wires generally have a much higher temperature rating than supply
wires, which enables them to carry higher current on smaller wires.

Since resistance increases with temperature, actual ampacity does not
increase much with an increase in temperature rating.

The temperature rating of a conductor depends on its *insulation*, not the
conductor itself. Ampacity *does* increase substantially with an increase in
temperature rating, due to the ability of the insulation to withstand a higher
conductor temperature.

Example: for copper wire, #8 TW has an ampacity of 40 amps; #8 THHN has an
ampacity of 55 amps.

Another example: #18 copper wire is permitted to carry 14 amps, IF it has 90
deg C insulation (e.g. THHN or THHW).

And ampacity
according to the code does not increase at all.

This simply is not true. See NEC Table 310.16 for abundant proof that the Code
absolutely does recognize increased ampacity for increased temperature
ratings.


--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Don Klipstein wrote:

Since resistance increases with temperature, actual ampacity does not
increase much with an increase in temperature rating. And ampacity
according to the code does not increase at all.

I'm going to have to disagree with that.

For simplicity, look at the "single conductor in free air" tables. (The
other tables show it too, just the absolute values are lower.)

With 60-90C rated insulation, a #14 wire is rated for 20A. With
110-125C rated insulation, that same size wire is rated for 40A. If you
go up to 200C insulation, you can put 45A through it.

Chris

No, he said he needed 16 feet. That's $8. You can buy it by the foot also.

--
Steve Barker


wrote in message
...
On Mon, 11 Dec 2006 10:53:59 -0600, "Steve Barker LT"
wrote:

OH, but that would have cost $8.

Where can you buy 50 feet of 12-2 for $8. Please tell me. I'll but
100 rolls immediately.

In article , Doug Miller wrote:
In article , (Don Klipstein) wrote:
In , Doug Miller wrote:
In ,marad :

I'm just curious how the code views that?

As a violation.

For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

Fixture wires generally have a much higher temperature rating than supply
wires, which enables them to carry higher current on smaller wires.

Since resistance increases with temperature, actual ampacity does not
increase much with an increase in temperature rating.

The temperature rating of a conductor depends on its *insulation*, not the
conductor itself. Ampacity *does* increase substantially with an increase in
temperature rating, due to the ability of the insulation to withstand a higher
conductor temperature.

Example: for copper wire, #8 TW has an ampacity of 40 amps; #8 THHN has an
ampacity of 55 amps.

Another example: #18 copper wire is permitted to carry 14 amps, IF it has 90
deg C insulation (e.g. THHN or THHW).

And ampacity
according to the code does not increase at all.

This simply is not true. See NEC Table 310.16 for abundant proof that the Code
absolutely does recognize increased ampacity for increased temperature
ratings.

This sounds to me specific to appliance cords, as opposed to romex.

- Don Klipstein )

In article , Chris Friesen wrote:
Don Klipstein wrote:

Since resistance increases with temperature, actual ampacity does not
increase much with an increase in temperature rating. And ampacity
according to the code does not increase at all.

I'm going to have to disagree with that.

For simplicity, look at the "single conductor in free air" tables. (The
other tables show it too, just the absolute values are lower.)

With 60-90C rated insulation, a #14 wire is rated for 20A. With
110-125C rated insulation, that same size wire is rated for 40A. If you
go up to 200C insulation, you can put 45A through it.

Somehow, I suspect that upgrading from 110 or 125 C insulation to 200 C
insulation only improving ampacity from 40 to 45 amps supports my point!

Meanwhile, also consider that wiring in a building is usually not single
conductor in free air, but 2 at least current-carrying conductors close to
each other and heating each other up with a sheath around them and the
environment outside the sheath usually not being "free air".

Add to this the fact that extra high temperature rating wire is used
more where ambient temperature is higher, and I see good reason for AWG 14
romex to be only allowed by code to be used in circuits up to 15 amps
regardless of temperature rating.

- Don Klipstein )

In article , (Don Klipstein) wrote:
In article , Doug Miller wrote:
In article , (Don
Klipstein) wrote:
In , Doug Miller wrote:
In ,marad :

I'm just curious how the code views that?

As a violation.

For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

Fixture wires generally have a much higher temperature rating than supply
wires, which enables them to carry higher current on smaller wires.

Since resistance increases with temperature, actual ampacity does not
increase much with an increase in temperature rating.

The temperature rating of a conductor depends on its *insulation*, not the
conductor itself. Ampacity *does* increase substantially with an increase in
temperature rating, due to the ability of the insulation to withstand a higher

conductor temperature.

Example: for copper wire, #8 TW has an ampacity of 40 amps; #8 THHN has an
ampacity of 55 amps.

Another example: #18 copper wire is permitted to carry 14 amps, IF it has 90
deg C insulation (e.g. THHN or THHW).

And ampacity
according to the code does not increase at all.

This simply is not true. See NEC Table 310.16 for abundant proof that the Code
absolutely does recognize increased ampacity for increased temperature
ratings.

This sounds to me specific to appliance cords, as opposed to romex.

Nope, wrong again. It applies to *all* premises wiring covered by the NEC.
There's a lot more than just "romex" involved.

Like I said... See NEC Table 310.16

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

In article , (Don Klipstein) wrote:
In article , Chris Friesen wrote:
Don Klipstein wrote:

Since resistance increases with temperature, actual ampacity does not
increase much with an increase in temperature rating. And ampacity
according to the code does not increase at all.

I'm going to have to disagree with that.

For simplicity, look at the "single conductor in free air" tables. (The
other tables show it too, just the absolute values are lower.)

With 60-90C rated insulation, a #14 wire is rated for 20A. With
110-125C rated insulation, that same size wire is rated for 40A. If you
go up to 200C insulation, you can put 45A through it.

Somehow, I suspect that upgrading from 110 or 125 C insulation to 200 C
insulation only improving ampacity from 40 to 45 amps supports my point!

Quite the opposite: it clearly contradicts your assertion that it "does not
increase at all". And, of course, the difference between 20A at 60 deg and 40A
at 125 deg makes that contradiction even more clear.

Meanwhile, also consider that wiring in a building is usually not single
conductor in free air, but 2 at least current-carrying conductors close to
each other and heating each other up with a sheath around them and the
environment outside the sheath usually not being "free air".

That was just an example -- and maybe not a real good one. But it does show
that (not to put too fine a point on it) you don't know what you're talking
about when you say that "ampacity according to the code does not increase at
all".

That's just not true.

See NEC Table 310.16 for abundant proof that the ampacity of a
conductor -- ANY conductor, ANY size -- absolutely DOES increase with
increasing temperature rating of the insulation.

Add to this the fact that extra high temperature rating wire is used
more where ambient temperature is higher, and I see good reason for AWG 14
romex to be only allowed by code to be used in circuits up to 15 amps
regardless of temperature rating.

That's a completely separate issue from the ampacity of the wire, which Code
specifies as being, for example, 25A with THHN insulation. In a separate
article, Code limits the overcurrent protection for 14 and 12 ga conductors to
15 and 20 amps, respectively, despite their having a higher ampacity.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

In article , Doug Miller wrote:
In article , (Don Klipstein) wrote:
In article , Chris Friesen wrote:
Don Klipstein wrote:

Since resistance increases with temperature, actual ampacity does not
increase much with an increase in temperature rating. And ampacity
according to the code does not increase at all.

I'm going to have to disagree with that.

For simplicity, look at the "single conductor in free air" tables. (The
other tables show it too, just the absolute values are lower.)

With 60-90C rated insulation, a #14 wire is rated for 20A. With
110-125C rated insulation, that same size wire is rated for 40A. If you
go up to 200C insulation, you can put 45A through it.

Somehow, I suspect that upgrading from 110 or 125 C insulation to 200 C
insulation only improving ampacity from 40 to 45 amps supports my point!

Quite the opposite: it clearly contradicts your assertion that it "does not
increase at all".

I did state that my "does not increase at all" was a code matter, on
which I would concede on appliance cords but I insist remains the case
with romex.

And, of course, the difference between 20A at 60 deg and 40A
at 125 deg makes that contradiction even more clear.

So you have cited a data point opposing my point as well as a data point
supporting my point (200C single conductor in free air good for 45 amps).

Meanwhile, also consider that wiring in a building is usually not single
conductor in free air, but 2 at least current-carrying conductors close to
each other and heating each other up with a sheath around them and the
environment outside the sheath usually not being "free air".

That was just an example -- and maybe not a real good one. But it does show
that (not to put too fine a point on it) you don't know what you're talking
about when you say that "ampacity according to the code does not increase at
all".

That's just not true.

Sure is true with most wiring, such as permanently installed wiring!
Code says 15 amps for AWG 14 regardless of temperature rating for
permanently installed wiring!

See NEC Table 310.16 for abundant proof that the ampacity of a
conductor -- ANY conductor, ANY size -- absolutely DOES increase with
increasing temperature rating of the insulation.

I google for that and find a nice chart:

http://www.houwire.com/products/tech...cle310_16.html

I see close to the top a line entry for 14 AWG, with no ampacities being
the 15 amps for 14 AWG permanently installed wiring, and I have already
conceded on the specific issue of appliance cords. Along with this chart
showing higher ampacities for specific cable types of which I think 97% or
so is not "permanently installed wiring". In addition, the code's limits
for "permanently installed wiring" do not appear to me to be increased
above 15 amps for 14 AWG or 20 amps for 12 AWG on the basis of such wiring
being allowed for "permanently installed wiring" (most of these cable
types are not) and such cable types having special ampacity higher than 15
amps for 14 AWG and 20 amps for 12 AWG.

Add to this the fact that extra high temperature rating wire is used
more where ambient temperature is higher, and I see good reason for AWG 14
romex to be only allowed by code to be used in circuits up to 15 amps
regardless of temperature rating.

That's a completely separate issue from the ampacity of the wire, which Code
specifies as being, for example, 25A with THHN insulation.

But does the Code allow AWG 14 with THNN insulation to be used in
permanently installed wiring in a building in circuits protected by fuses
or breakers of more than 15 amps?
Since I conceded on appliance cords, I still consider the issue of
permanently installed wiring to be valid!

In a separate
article, Code limits the overcurrent protection for 14 and 12 ga conductors to
15 and 20 amps, respectively, despite their having a higher ampacity.

Starting to sound like what I am saying, especially in terms of code?

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

- Don Klipstein )

Hire a professional

On Mon, 11 Dec 2006 09:12:41 -0600, wrote:

I am wondering how the code views this. I was just wiring my barn and
ran out of 12-2 romex. Rather than buy more, I decided to just use
14-2 since I had 200 feet of it. This 14-2 is only going to one
light, one of those porcelin fixtures that are rated at 100W.

As far as safety, I am not worried in the least. It's only going to
run one 100W bulb (or less). As far as being inspected, I am also not
worried. In barns and sheds they really dont care, unless there are
bare wires or some obvious danger source. I'm just curious how the
code views that? For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

In my case, I have one center light fed by #12, and one light on the
left another on the right. Each of those lights are fed off the
center light with about 16 feet of #14.

Thanks

Mark

In article , (Don Klipstein) wrote:
In article , Doug Miller
wrote:
In article , (Don
Klipstein) wrote:
In article , Chris Friesen wrote:
Don Klipstein wrote:

Since resistance increases with temperature, actual ampacity does not
increase much with an increase in temperature rating. And ampacity
according to the code does not increase at all.

I'm going to have to disagree with that.

For simplicity, look at the "single conductor in free air" tables. (The
other tables show it too, just the absolute values are lower.)

With 60-90C rated insulation, a #14 wire is rated for 20A. With
110-125C rated insulation, that same size wire is rated for 40A. If you
go up to 200C insulation, you can put 45A through it.

Somehow, I suspect that upgrading from 110 or 125 C insulation to 200 C
insulation only improving ampacity from 40 to 45 amps supports my point!

Quite the opposite: it clearly contradicts your assertion that it "does not
increase at all".

I did state that my "does not increase at all" was a code matter,

Yes, you did -- and I have repeatedly pointed out that this is not correct,
that the Code absolutely does recognize increased ampacity with increasing
conductor temperature.

The entire Code is online he
http://nfpa-acs-01.gvpi.net:8080/rrs...NFPASTD/7005SB

I refer you to Table 310.16.

on
which I would concede on appliance cords but I insist remains the case
with romex.

You're commenting in a vacuum, based on a lack of knowledge. Read the Code.
You're wrong.


And, of course, the difference between 20A at 60 deg and 40A
at 125 deg makes that contradiction even more clear.

So you have cited a data point opposing my point as well as a data point
supporting my point (200C single conductor in free air good for 45 amps).

Read the Code. You're wrong. Table 310.16.

Meanwhile, also consider that wiring in a building is usually not single
conductor in free air, but 2 at least current-carrying conductors close to
each other and heating each other up with a sheath around them and the
environment outside the sheath usually not being "free air".

That was just an example -- and maybe not a real good one. But it does show
that (not to put too fine a point on it) you don't know what you're talking
about when you say that "ampacity according to the code does not increase at
all".

That's just not true.

Sure is true with most wiring, such as permanently installed wiring!
Code says 15 amps for AWG 14 regardless of temperature rating for
permanently installed wiring!

Read the Code. You're wrong. Table 310.16.

See NEC Table 310.16 for abundant proof that the ampacity of a
conductor -- ANY conductor, ANY size -- absolutely DOES increase with
increasing temperature rating of the insulation.

I google for that and find a nice chart:

http://www.houwire.com/products/tech...cle310_16.html

I see close to the top a line entry for 14 AWG, with no ampacities being
the 15 amps for 14 AWG permanently installed wiring, and I have already
conceded on the specific issue of appliance cords. Along with this chart
showing higher ampacities for specific cable types of which I think 97% or
so is not "permanently installed wiring". In addition, the code's limits
for "permanently installed wiring" do not appear to me to be increased
above 15 amps for 14 AWG or 20 amps for 12 AWG on the basis of such wiring
being allowed for "permanently installed wiring" (most of these cable
types are not) and such cable types having special ampacity higher than 15
amps for 14 AWG and 20 amps for 12 AWG.

Read the Code. You're wrong. Table 310.16.
Add to this the fact that extra high temperature rating wire is used
more where ambient temperature is higher, and I see good reason for AWG 14
romex to be only allowed by code to be used in circuits up to 15 amps
regardless of temperature rating.

That's a completely separate issue from the ampacity of the wire, which Code
specifies as being, for example, 25A with THHN insulation.

But does the Code allow AWG 14 with THNN insulation to be used in
permanently installed wiring in a building in circuits protected by fuses
or breakers of more than 15 amps?

No -- but that's because the Code builds the "80% rule" into the overcurrent
protection limits for 10, 14, and 12ga conductors, not because of any limits
on the conductor's ability to carry current. It's for additional safety. But
if you would actually READ THE CODE, you'd find out that the ampacities are in
fact considerably higher than the permitted overcurrent protection. It's two
separate issues.
Since I conceded on appliance cords, I still consider the issue of
permanently installed wiring to be valid!

Read the Code. You're wrong. Table 310.16.

In a separate
article, Code limits the overcurrent protection for 14 and 12 ga conductors to
15 and 20 amps, respectively, despite their having a higher ampacity.

Starting to sound like what I am saying, especially in terms of code?

No, it's NOT starting to sound like what you're saying. You said that,
according to Code, conductor ampacity "does not increase at all" with
increased conductor temperature rating, and that simply is not true. Not for
fixture wires. Not for appliance cords. Not for permanently installed wiring.
Not true at all.

READ THE CODE.

Table 310.16.

--
Regards,
Doug Miller (alphageek at milmac dot com)

It's time to throw all their damned tea in the harbor again.

Abe wrote:

Why not avoid any potential problems and just buy a 15 amp breaker for
a few bucks?
..
Exactly:

Had one situation where we realzed that a circuit extended out to shed
from a 20 amp circuit included some #14AWG.

We quickly changed out the 20 amp breaker to 15 amp not because of any
problems but a) to meet code b) Demonstrate for an in impending
insurance inspection (the first in the 36 years since house was built!)
that wiring was built and maintained to standard.

Reminds me got one cracked duplex at the bench must change it. And
although its indoors think I'll make the first one on that run a GFI.

In , Doug Miller wrote in
part:

No -- but that's because the Code builds the "80% rule" into the overcurrent
protection limits for 10, 14, and 12ga conductors, not because of any limits
on the conductor's ability to carry current. It's for additional safety. But
if you would actually READ THE CODE, you'd find out that the ampacities
are in fact considerably higher than the permitted overcurrent
protection. It's two separate issues.

OK, I learned something here - the issue that I was thinking of, where
15 amps is the limit for AWG 14 permanently installed wiring regardless of
its temperature rating, is called "permitted overcurrent protection".

- Don Klipstein )

wrote:
Hire a professional

On Mon, 11 Dec 2006 09:12:41 -0600, wrote:

I am wondering how the code views this. I was just wiring my barn and
ran out of 12-2 romex. Rather than buy more, I decided to just use
14-2 since I had 200 feet of it. This 14-2 is only going to one
light, one of those porcelin fixtures that are rated at 100W.
This is a do-it-yourself NG. What are you doing here?

John


As far as safety, I am not worried in the least. It's only going to
run one 100W bulb (or less). As far as being inspected, I am also not
worried. In barns and sheds they really dont care, unless there are
bare wires or some obvious danger source. I'm just curious how the
code views that? For example, if I but a common house type ceiling
fixture, they generally have 8 inches or up to several feet (on a
chandlier) of #14 standed wire as part of the fixture. So, if I am
running a 20A circuit I am already using #14 in the circuit.

In my case, I have one center light fed by #12, and one light on the
left another on the right. Each of those lights are fed off the
center light with about 16 feet of #14.

Thanks

Mark