Hello,
I'm adding some recessed lighting in my basement. The wiring that is there
consists of some 14/2 wire and 12/2 wire for the existing recessed lights.
There are 4 of them right now. I was wanting to add 6 more on one 15 amp
circuit. The bulb themselves would be 65 watt spots. Will one 15 amp circuit
handle 6 lights? Can I get away with using 14/2 NM wire or should I use the
heavier 12/2 on the new circuit? When all is done I would have 2 -15 amp
circuits that have 6 recessed lights each. Is this safe?

Thanks in advance,
Joseph
Indiana

Hello,
I'm adding some recessed lighting in my basement. The wiring that is there
consists of some 14/2 wire and 12/2 wire for the existing recessed lights.
There are 4 of them right now. I was wanting to add 6 more on one 15 amp
circuit. The bulb themselves would be 65 watt spots. Will one 15 amp circuit
handle 6 lights? Can I get away with using 14/2 NM wire or should I use the
heavier 12/2 on the new circuit? When all is done I would have 2 -15 amp
circuits that have 6 recessed lights each. Is this safe?

Thanks in advance,
Joseph
Indiana

A fifteen ampere circuit will carry a continuous load such as lighting
of 1440 volt / amperes. A twenty ampere circuit will carry 1920. Do
the math. Divide the circuits available VA capacity by the VA of the
installed lamps and you will get the number of lamps that the circuit
will carry. As long as the lamps are incandescent the wattage of the
lamps can be used as the VA of the lamps.
--
Tom

On 26 Oct 2003, JosephM wrote:

Hello,
I'm adding some recessed lighting in my basement. The wiring that is
there consists of some 14/2 wire and 12/2 wire for the existing
recessed lights. There are 4 of them right now. I was wanting to add 6
more on one 15 amp circuit. The bulb themselves would be 65 watt
spots. Will one 15 amp circuit handle 6 lights? Can I get away with
using 14/2 NM wire or should I use the heavier 12/2 on the new
circuit? When all is done I would have 2 -15 amp circuits that have 6
recessed lights each. Is this safe?

Absolutely.

15A @ 120V = 1800 watts, so if the fixtures themselves were
rated as such (they usually aren't) you could run 6 * 250
watt bulbs without going over 15A (6*250=1500W=12.5A)

That's -exactly- the type of circuit that 14 guage wire is
made for. Actually, you could put all 12 fixtures on one
circuit (and break them up into as many switched branches as
you want to.) If you would use a 100W bulb in each, you're
still only be talking about 1200W = 10A @ 120V. There's
really no need to tie up a 2nd breaker for two circuits.

--
Baisez-les s'ils ne peuvent pas prendre une plaisanterie
--------------------------------------------------------
Tom Pendergast e-mail is for sissies, say it on line

"JosephM" wrote in message
news:2i0nb.29265$9E1.110167@attbi_s52...
Hello,
I'm adding some recessed lighting in my basement. The wiring that is there
consists of some 14/2 wire and 12/2 wire for the existing recessed lights.
There are 4 of them right now. I was wanting to add 6 more on one 15 amp
circuit. The bulb themselves would be 65 watt spots. Will one 15 amp
circuit
handle 6 lights? Can I get away with using 14/2 NM wire or should I use
the
heavier 12/2 on the new circuit? When all is done I would have 2 -15 amp
circuits that have 6 recessed lights each. Is this safe?

Thanks in advance,
Joseph
Indiana


this is turtle.

It seem here your over killing here a good bit. The 12 -- 65 watt lite will
pull about 4 to 5 amps and you can combine the 12 lite on 1 -- 20 amp / 1 --
15 amp circuit with #12/2 and cut down on all the circuits in your home.
Less circuits / less trouble down the road. Now you can't have a bunch of
other stuff on here too and add the 12 lites together.

Now you could just use the 14 wire and 1 -- 15 amp breaker to run the hold
thing.

TURTLE

Tom Horne wrote:
Hello,
I'm adding some recessed lighting in my basement. The wiring that is
there
consists of some 14/2 wire and 12/2 wire for the existing recessed
lights.
There are 4 of them right now. I was wanting to add 6 more on one 15 amp
circuit. The bulb themselves would be 65 watt spots. Will one 15 amp
circuit
handle 6 lights? Can I get away with using 14/2 NM wire or should I
use the
heavier 12/2 on the new circuit? When all is done I would have 2 -15 amp
circuits that have 6 recessed lights each. Is this safe?

Thanks in advance,
Joseph
Indiana


A fifteen ampere circuit will carry a continuous load such as lighting
of 1440 volt / amperes. A twenty ampere circuit will carry 1920. Do
the math. Divide the circuits available VA capacity by the VA of the
installed lamps and you will get the number of lamps that the circuit
will carry. As long as the lamps are incandescent the wattage of the
lamps can be used as the VA of the lamps.
--
Tom

Hi,
VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.
Tony

In article Wl3nb.194451$9l5.193936@pd7tw2no, Tony Hwang wrote:
Tom Horne wrote:
As long as the lamps are incandescent the wattage of the
lamps can be used as the VA of the lamps.

VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.

As far as a purely resistive load such as an incandescent lamp is concerned,
they are indeed equal.

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

In article , "I-zheet M'drurz" wrote:
On 26 Oct 2003, JosephM wrote:

Hello,
I'm adding some recessed lighting in my basement. The wiring that is
there consists of some 14/2 wire and 12/2 wire for the existing
recessed lights. There are 4 of them right now. I was wanting to add 6
more on one 15 amp circuit. The bulb themselves would be 65 watt
spots. Will one 15 amp circuit handle 6 lights? Can I get away with
using 14/2 NM wire or should I use the heavier 12/2 on the new
circuit? When all is done I would have 2 -15 amp circuits that have 6
recessed lights each. Is this safe?

Absolutely.

15A @ 120V = 1800 watts, so if the fixtures themselves were
rated as such (they usually aren't) you could run 6 * 250
watt bulbs without going over 15A (6*250=1500W=12.5A)

You forget that, for continuous loads, the circuit is limited to 80% of its
rated capacity. This is the calculation you should have used:

15A @ 120V x 80% = 1440 watts.

He's still within the limit, of course, but the limit isn't as high as you
claim.

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

"Tony Hwang" wrote in message
news:Wl3nb.194451$9l5.193936@pd7tw2no...


Tom Horne wrote:
Hello,
I'm adding some recessed lighting in my basement. The wiring that is
there
consists of some 14/2 wire and 12/2 wire for the existing recessed
lights.
There are 4 of them right now. I was wanting to add 6 more on one 15
amp
circuit. The bulb themselves would be 65 watt spots. Will one 15 amp
circuit
handle 6 lights? Can I get away with using 14/2 NM wire or should I
use the
heavier 12/2 on the new circuit? When all is done I would have 2 -15
amp
circuits that have 6 recessed lights each. Is this safe?

Thanks in advance,
Joseph
Indiana


A fifteen ampere circuit will carry a continuous load such as lighting
of 1440 volt / amperes. A twenty ampere circuit will carry 1920. Do
the math. Divide the circuits available VA capacity by the VA of the
installed lamps and you will get the number of lamps that the circuit
will carry. As long as the lamps are incandescent the wattage of the
lamps can be used as the VA of the lamps.
--
Tom

Hi,
VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.
Tony

Probably why Tom Horne specifically stated "as long as the lamps are
incandescent..." For calculating purposes, the PF of a resistive load
(such as an incandescent light) is PF = 1, thus VA = Watts, for a resistive
load. If an inductive load is served (such as fluorescent light fixtures),
_then_ the PF must be considered, in which case, to calculate VA one must
use the amp draw printed on the fluorescent light _ballast_ label, _not_
the amp draw as "calculated" from the wattage of the fluorescent lamp(s).

Tony Hwang wrote in message news:Wl3nb.194451$9l5.193936@pd7tw2no...
Hi,
VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.
Tony

LMAO. What do you suppose the power factor of a light bulb is?

Doug Miller wrote:

In article Wl3nb.194451$9l5.193936@pd7tw2no, Tony Hwang wrote:

Tom Horne wrote:

As long as the lamps are incandescent the wattage of the
lamps can be used as the VA of the lamps.


VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.


As far as a purely resistive load such as an incandescent lamp is concerned,
they are indeed equal.

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

Hi,
Since you used word PURELY, even the filament of incandescent bulb has
inductance, how could it be pure R without X? I still stick my gun on
my statement. Watts is not equal to VA, better give some margin.
Tony

Zaf wrote:

Tony Hwang wrote in message news:Wl3nb.194451$9l5.193936@pd7tw2no...

Hi,
VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.
Tony


LMAO. What do you suppose the power factor of a light bulb is?

Hi,
That kind of thinking could cause problems in the field. I said math. As
long as one knows what it is.
Tony

Hi,
VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.
Tony

I didn't say it was equal in all cases. What I said was that for
incandescent bulbs the value given in watts can be used as the VA value.
--
Tom

In article C4bnb.197307$pl3.160437@pd7tw3no, Tony Hwang wrote:


Doug Miller wrote:

In article Wl3nb.194451$9l5.193936@pd7tw2no, Tony Hwang
wrote:

Tom Horne wrote:

As long as the lamps are incandescent the wattage of the
lamps can be used as the VA of the lamps.


VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.


As far as a purely resistive load such as an incandescent lamp is concerned,
they are indeed equal.

Hi,
Since you used word PURELY, even the filament of incandescent bulb has
inductance, how could it be pure R without X? I still stick my gun on
my statement. Watts is not equal to VA, better give some margin.
Tony

OK, why don't you do the math, and tell us how much difference there is
between watts and volt-amperes for, say, a 60-watt incandescent light bulb?

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

Doug Miller wrote:

In article C4bnb.197307$pl3.160437@pd7tw3no, Tony Hwang wrote:


Doug Miller wrote:


In article Wl3nb.194451$9l5.193936@pd7tw2no, Tony Hwang

wrote:

Tom Horne wrote:


As long as the lamps are incandescent the wattage of the
lamps can be used as the VA of the lamps.


VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.


As far as a purely resistive load such as an incandescent lamp is concerned,
they are indeed equal.


Hi,
Since you used word PURELY, even the filament of incandescent bulb has
inductance, how could it be pure R without X? I still stick my gun on
my statement. Watts is not equal to VA, better give some margin.
Tony


OK, why don't you do the math, and tell us how much difference there is
between watts and volt-amperes for, say, a 60-watt incandescent light bulb?

--
Regards,
Doug Miller (alphageek-at-milmac-dot-com)
Hi,
Also wiring has inductance. If I install 15A circuit, I'd let it carry
~13A and have peace in mind. Are you going to give full load in your
case then?
Tony

"Tony Hwang" wrote in message
news:sywnb.206443$pl3.17868@pd7tw3no...


Doug Miller wrote:

In article C4bnb.197307$pl3.160437@pd7tw3no, Tony Hwang
wrote:


Doug Miller wrote:


In article Wl3nb.194451$9l5.193936@pd7tw2no, Tony Hwang


wrote:

Tom Horne wrote:


As long as the lamps are incandescent the wattage of the
lamps can be used as the VA of the lamps.


VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.


As far as a purely resistive load such as an incandescent lamp is
concerned,
they are indeed equal.


Hi,
Since you used word PURELY, even the filament of incandescent bulb has
inductance, how could it be pure R without X? I still stick my gun on
my statement. Watts is not equal to VA, better give some margin.
Tony


OK, why don't you do the math, and tell us how much difference there is
between watts and volt-amperes for, say, a 60-watt incandescent light
bulb?

--
Regards,
Doug Miller (alphageek-at-milmac-dot-com)
Hi,
Also wiring has inductance. If I install 15A circuit, I'd let it carry
~13A and have peace in mind. Are you going to give full load in your
case then?
Tony


Tony, your argument holds about as much water as a tiny piece of pork (fat)
in a can of "Pork" and Beans.......interesting how the pork is always listed
_first_.

The reason why the NEC limits a continuously loaded lighting circuit
(defined by the NEC as a circuit expected to remain on for 3 or more hours)
to 80% (that's 12 amps for a 15 amp circuit) is because the circuit breaker
will start to nuisance trip when left on for an extended period of time if
the full 15 amps is applied continuously, _not_ some ridiculous argument
about the minuscule amount of inductance in an incandescent lamp.

On 28 Oct 2003, volts500 wrote:

_not_ some ridiculous argument about the minuscule amount of
inductance in an incandescent lamp.

Uh huh (snicker). And any discussion of this subject
(inductance, AC power factor and phase relationships, Xl
and Xc) is beyond your area of knowledge, you've already
told us that when I brought it up months ago.

I get it now, Volts. You donut understand it, it becomes
"ridiculous" and "miniscule".

Stick to wiring whips for air conditioners, you won't strain
yourself that way.

--
Baisez-les s'ils ne peuvent pas prendre une plaisanterie
--------------------------------------------------------
Tom Pendergast e-mail is for sissies, say it on line

"I-zheet M'drurz" wrote in message
...
On 28 Oct 2003, volts500 wrote:

_not_ some ridiculous argument about the minuscule amount of
inductance in an incandescent lamp.

Uh huh (snicker). And any discussion of this subject
(inductance, AC power factor and phase relationships, Xl
and Xc) is beyond your area of knowledge, you've already
told us that when I brought it up months ago.


Yeah, I remember tried to tell us that a toaster is an inductive load and a
fan motor was a capacitive load. BRAHAHAHAHAHA, I'm still laughing about
that. Doesn't surprise me that you also think that an incandescent lamp is
a significant inductive load just because the filaments are coiled.
ROTFLMAO.

For a resistive load cosine(phi)=1.

Boden

Tony Hwang wrote:



Tom Horne wrote:

Hello,
I'm adding some recessed lighting in my basement. The wiring that is
there
consists of some 14/2 wire and 12/2 wire for the existing recessed
lights.
There are 4 of them right now. I was wanting to add 6 more on one 15 amp
circuit. The bulb themselves would be 65 watt spots. Will one 15 amp
circuit
handle 6 lights? Can I get away with using 14/2 NM wire or should I
use the
heavier 12/2 on the new circuit? When all is done I would have 2 -15
amp
circuits that have 6 recessed lights each. Is this safe?

Thanks in advance,
Joseph
Indiana



A fifteen ampere circuit will carry a continuous load such as lighting
of 1440 volt / amperes. A twenty ampere circuit will carry 1920. Do
the math. Divide the circuits available VA capacity by the VA of the
installed lamps and you will get the number of lamps that the circuit
will carry. As long as the lamps are incandescent the wattage of the
lamps can be used as the VA of the lamps.
--
Tom

Hi,
VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.
Tony

Have you ever measured the inductance of a lamp filament? It's
insignificant.

Boden

Tony Hwang wrote:



Doug Miller wrote:

In article Wl3nb.194451$9l5.193936@pd7tw2no, Tony Hwang
wrote:

Tom Horne wrote:

As long as the lamps are incandescent the wattage of the lamps can
be used as the VA of the lamps.



VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.



As far as a purely resistive load such as an incandescent lamp is
concerned, they are indeed equal.

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


Hi,
Since you used word PURELY, even the filament of incandescent bulb has
inductance, how could it be pure R without X? I still stick my gun on
my statement. Watts is not equal to VA, better give some margin.
Tony

volts500 wrote:

"Tony Hwang" wrote in message
news:sywnb.206443$pl3.17868@pd7tw3no...


Doug Miller wrote:


In article C4bnb.197307$pl3.160437@pd7tw3no, Tony Hwang

wrote:

Doug Miller wrote:



In article Wl3nb.194451$9l5.193936@pd7tw2no, Tony Hwang



wrote:


Tom Horne wrote:



As long as the lamps are incandescent the wattage of the
lamps can be used as the VA of the lamps.


VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.


As far as a purely resistive load such as an incandescent lamp is

concerned,

they are indeed equal.


Hi,
Since you used word PURELY, even the filament of incandescent bulb has
inductance, how could it be pure R without X? I still stick my gun on
my statement. Watts is not equal to VA, better give some margin.
Tony


OK, why don't you do the math, and tell us how much difference there is
between watts and volt-amperes for, say, a 60-watt incandescent light

bulb?

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

Hi,
Also wiring has inductance. If I install 15A circuit, I'd let it carry
~13A and have peace in mind. Are you going to give full load in your
case then?
Tony



Tony, your argument holds about as much water as a tiny piece of pork (fat)
in a can of "Pork" and Beans.......interesting how the pork is always listed
_first_.

The reason why the NEC limits a continuously loaded lighting circuit
(defined by the NEC as a circuit expected to remain on for 3 or more hours)
to 80% (that's 12 amps for a 15 amp circuit) is because the circuit breaker
will start to nuisance trip when left on for an extended period of time if
the full 15 amps is applied continuously, _not_ some ridiculous argument
about the minuscule amount of inductance in an incandescent lamp.

Hi,
15A breaker won't trip at 15A. Depending on what kinds, it has to be
over 15A. The delay time is different. Just like fuses, fast blow vs.
slow blow. Like 15A fuse does not blow at 15A. Hardly any electrical
load is pure resistance. They're mostly inductive load. Never saw a
phase correcting capacitor banks in commercial buildings? Inductance
causes surge when power is turend on. Tell me one pure resistive load in
any utility grid.
In non-DC circuit we talk about impedance(combination of resistance and
reactance; sum of inductive and capacitive reactance)
As an example, again I emphasize example, not real figures,
a 60W light bulb has 6 Ohm resistance and 1 micro Henry reactance.
Impedance at 60Hz is root of 6+(2 x Pi x 60 x 1/1000,000). Definitely
more tahn 6 Ohms.
This thread is closed for me.
Tony

I-zheet M'drurz wrote:

On 28 Oct 2003, volts500 wrote:


_not_ some ridiculous argument about the minuscule amount of
inductance in an incandescent lamp.


Uh huh (snicker). And any discussion of this subject
(inductance, AC power factor and phase relationships, Xl
and Xc) is beyond your area of knowledge, you've already
told us that when I brought it up months ago.

I get it now, Volts. You donut understand it, it becomes
"ridiculous" and "miniscule".

Stick to wiring whips for air conditioners, you won't strain
yourself that way.

Hi,
I had an electrician who wired emergency shut down of a big computer
room from blue print. When test time came after completing the wiring,
I pushed big red button, nothing happened. Ooops! nothing went down.
This so called licensed electrician couldn't even read simple relay
logic mixed with 24V and 120V control circuits. I had to tell him what
to do. Maybe this guy is his brother or co-worker. This kind of folks
are trouble makers in the field.
I am retired but I still keep my basic knowledge. I don't invent or bend
rule of physics.
Tony

Hi,
Which is power factor of 1(phase angle is aero). No loss circuit.
Pure resistive load which does not hardly exist in real world.
Cos0(zer degrees) = 1.
Thanks, Boden.
Tony


Boden wrote:

For a resistive load cosine(phi)=1.

Boden

Tony Hwang wrote:



Tom Horne wrote:

Hello,
I'm adding some recessed lighting in my basement. The wiring that is
there
consists of some 14/2 wire and 12/2 wire for the existing recessed
lights.
There are 4 of them right now. I was wanting to add 6 more on one 15
amp
circuit. The bulb themselves would be 65 watt spots. Will one 15 amp
circuit
handle 6 lights? Can I get away with using 14/2 NM wire or should I
use the
heavier 12/2 on the new circuit? When all is done I would have 2
-15 amp
circuits that have 6 recessed lights each. Is this safe?

Thanks in advance,
Joseph
Indiana




A fifteen ampere circuit will carry a continuous load such as
lighting of 1440 volt / amperes. A twenty ampere circuit will carry
1920. Do the math. Divide the circuits available VA capacity by the
VA of the installed lamps and you will get the number of lamps that
the circuit will carry. As long as the lamps are incandescent the
wattage of the lamps can be used as the VA of the lamps.
--
Tom

Hi,
VA is not equal to Watts. Reason? Power factor, Cosine Phi.
As far as math is concerned.
Tony

On 28 Oct 2003, Tony Hwang wrote:

Hi,
Which is power factor of 1(phase angle is aero). No loss circuit.
Pure resistive load which does not hardly exist in real world.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
That's the key here. Thank you for saying it, prepare to
be belittled and badgered by those too simple minded to
understand.

Cos0(zer degrees) = 1.

--
Baisez-les s'ils ne peuvent pas prendre une plaisanterie
--------------------------------------------------------
Tom Pendergast e-mail is for sissies, say it on line

"Tony Hwang" wrote in message
news:C4bnb.197307$pl3.160437@pd7tw3no...

Hi,
Since you used word PURELY, even the filament of incandescent bulb has
inductance, how could it be pure R without X? I still stick my gun on
my statement. Watts is not equal to VA, better give some margin.
Tony

at 60 Hz, the inductance of a filament is irrelevant. We're not in the
microwave range...

"Tony Hwang" wrote in message
news:qiEnb.209121$9l5.101766@pd7tw2no...
As an example, again I emphasize example, not real figures,
a 60W light bulb has 6 Ohm resistance and 1 micro Henry reactance.
Impedance at 60Hz is root of 6+(2 x Pi x 60 x 1/1000,000). Definitely
more tahn 6 Ohms.

oh my god, you're right!!!!!
it's 6.0003 ohms!

This thread is closed for me.

yah, I think it is...

"Tony Hwang" wrote in message
news:qiEnb.209121$9l5.101766@pd7tw2no...

volts 500 wrote:

Tony, your argument holds about as much water as a tiny piece of pork
(fat)
in a can of "Pork" and Beans.......interesting how the pork is always
listed
_first_.

The reason why the NEC limits a continuously loaded lighting circuit
(defined by the NEC as a circuit expected to remain on for 3 or more
hours)
to 80% (that's 12 amps for a 15 amp circuit) is because the circuit
breaker
will start to nuisance trip when left on for an extended period of time
if
the full 15 amps is applied continuously, _not_ some ridiculous argument
about the minuscule amount of inductance in an incandescent lamp.

Tony Hwang wrote:

Hi,
15A breaker won't trip at 15A.

It most certainly will trip, given time. That's the whole purpose of the
NEC requirement to limit a continuous load to 80% capacity.....prevent
nuisance tripping.

Depending on what kinds, it has to be
over 15A. The delay time is different. Just like fuses, fast blow vs.
slow blow. Like 15A fuse does not blow at 15A. Hardly any electrical
load is pure resistance. They're mostly inductive load. Never saw a
phase correcting capacitor banks in commercial buildings?


I've installed plenty of them. Try a synchronous condenser some time. _DO_
tell me the _correct_ required wire size (THWN) for a 100 kVAR capacitor
bank connected to a 3 phase 277/480 volt Wye connected system........that
is, if you know how to calculate amps for the given kVAR.


Inductance
causes surge when power is turend on. Tell me one pure resistive load in
any utility grid.


Tell me one pure inductive load in any utility grid.


In non-DC circuit we talk about impedance(combination of resistance and
reactance; sum of inductive and capacitive reactance)
As an example, again I emphasize example, not real figures,
a 60W light bulb has 6 Ohm resistance and 1 micro Henry reactance.
Impedance at 60Hz is root of 6+(2 x Pi x 60 x 1/1000,000). Definitely
more tahn 6 Ohms.
This thread is closed for me.
Tony

I can see why.

j j wrote:

"Tony Hwang" wrote in message
news:C4bnb.197307$pl3.160437@pd7tw3no...


Hi,
Since you used word PURELY, even the filament of incandescent bulb has
inductance, how could it be pure R without X? I still stick my gun on
my statement. Watts is not equal to VA, better give some margin.
Tony


at 60 Hz, the inductance of a filament is irrelevant. We're not in the
microwave range...

Hi,
Knit picking. I am RF guy.
Tony, VE6CGX

"Tony Hwang" wrote in message
news:6oEnb.209736$6C4.131771@pd7tw1no...

Hi,
I had an electrician who wired emergency shut down of a big computer
room from blue print. When test time came after completing the wiring,
I pushed big red button, nothing happened. Ooops! nothing went down.
This so called licensed electrician couldn't even read simple relay
logic mixed with 24V and 120V control circuits. I had to tell him what
to do.

That works two ways don't ya know. I've seen plenty of stamped and signed
blueprints that were not correct......everybody makes mistakes. A shunt
trip is soooooooooo hard to wire, huh Tony? _DO_ tell us how the HVAC
shutdown and the fire dampers were incorporated into the deal.


Maybe this guy is his brother or co-worker. This kind of folks
are trouble makers in the field.


Make me wonder how _you_ managed to get on top of last year's list of AHR's
"Who's Who of Useless Posters."


I am retired but I still keep my basic knowledge. I don't invent or bend
rule of physics.
Tony

Geez, you sure about that Tony? _DO_ tell us how that "air" core resulting
from coiling the ni-chrome wire for the incandescent lamp filament creates
that overwhelming inductance. Funny how the engineers and other
professionals who write the NEC consider inductance to be insignificant when
making calculations for resistive loads......or is it just that they are
morons too?

"I-zheet M'drurz" wrote in message
...
On 28 Oct 2003, Tony Hwang wrote:

Hi,
Which is power factor of 1(phase angle is aero). No loss circuit.
Pure resistive load which does not hardly exist in real world.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
That's the key here. Thank you for saying it, prepare to
be belittled and badgered by those too simple minded to
understand.

The only simpletons here are the morons like you who insist that the
minuscule amount inductance in an incandescent lamp somehow becomes a
significant factor when calculating the VA of a resistive load. Tell us
again, Tomi Boi, how is it that you came to the conclusion that a toaster is
an inductive load and a vacuum motor is a capacitive load?
http://tinyurl.com/st7a

"I-zheet M'drurz" wrote in message ...
On 28 Oct 2003, Tony Hwang wrote:

Hi,
Which is power factor of 1(phase angle is aero). No loss circuit.
Pure resistive load which does not hardly exist in real world.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
That's the key here. Thank you for saying it, prepare to
be belittled and badgered by those too simple minded to
understand.

Cos0(zer degrees) = 1.

Yes, be prepared to be belittled. Incandescent Lights are indeed near
perfect resistive loads and as far as I kow they do exist in the real
world.

Electric water heaters (and to a lesser degree dryers), near perfect
resistors, their job is to dissipate heat. Yes, if you are running an
air conditioner or fridge yes, there will be 10-15% reactive portion.
High crest factor current waveforms (in electronics) can also impact
usable power on a given breaker, but this is well beyond the scope of
the question. The question in this case will can ten 65 watt bulbs be
safe off a 15 amp circuit and the answer is yes, by more then factor
of 2.

Furthermore cos(phi) is an oversimplified for PF. Total power (real +
reactive) is the integral of the product of the voltage and current.
The current in many electronics devices being nonsinusoidal. Finally,
mathamatics is the TOOL quantify the PHYSICS in this problem. Circuit
breakers do not do math, they do follow the laws of PHYSICS. Now that
you have been belittled by someone simple minded perhaps you will not
post that which you are ill informed on.

"volts500" wrote in message
om...

"Tony Hwang" wrote in message
news:qiEnb.209121$9l5.101766@pd7tw2no...

volts 500 wrote:

Tony, your argument holds about as much water as a tiny piece of pork
(fat)
in a can of "Pork" and Beans.......interesting how the pork is always
listed
_first_.

The reason why the NEC limits a continuously loaded lighting circuit
(defined by the NEC as a circuit expected to remain on for 3 or more
hours)
to 80% (that's 12 amps for a 15 amp circuit) is because the circuit
breaker
will start to nuisance trip when left on for an extended period of
time
if
the full 15 amps is applied continuously, _not_ some ridiculous
argument
about the minuscule amount of inductance in an incandescent lamp.

Tony Hwang wrote:

Hi,
15A breaker won't trip at 15A.

It most certainly will trip, given time. That's the whole purpose of the
NEC requirement to limit a continuous load to 80% capacity.....prevent
nuisance tripping.

I had a 15 amp breaker that tripped when the load was 20 amps (that's what I
calculated, with computers, TV, lights and a 1100 watt blowdrier). I asked
the electrician about it and he said breakers trip at different currents,
depending on how long they stay at that current.
since a breaker works by heating, it will take let's say 10 seconds to trip
at 20 amps and maybe a minute to trip at 17 amps, but yes, if left at 15
amps constantly it will trip after a while because it heats up.

"Tony Hwang" wrote in message
news:C%Hnb.210864$pl3.59615@pd7tw3no...


j j wrote:

"Tony Hwang" wrote in message
news:C4bnb.197307$pl3.160437@pd7tw3no...


Hi,
Since you used word PURELY, even the filament of incandescent bulb has
inductance, how could it be pure R without X? I still stick my gun on
my statement. Watts is not equal to VA, better give some margin.
Tony


at 60 Hz, the inductance of a filament is irrelevant. We're not in the
microwave range...

Hi,
Knit picking. I am RF guy.

then you know that engineering is based on approximations.
at RF frequencies the inductance can't be ignored, but for a power engineer,
at 60 hertz, the load is purely resistive.
the difference between 6 ohms and 6.0003 is irrelevant in this context.