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On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, wrote:

Larry Jaques wrote:

Ayup, it's time to start cuttin' into that drywall if you didn't wire
for the entire ceiling. Add that switch while you're at it. 3 rows of
3 fixtures with 2 rows of 2 in between them, switched for even and odd
rows. 3' spacing between rows instead of 4', or go 2' from walls and
keep the 4' row spacing.

---- ---- ----
---- ---- (door side)
---- ---- ----
---- ----
---- ---- ----

It's closer to Lew's modeling (way too much, IMHO) but it's switchable
to avoid the need for sunglasses. Pure white EGGSHELL paint is the
perfect mix for reflection without glare or thrown shadows.


Larry,
Here are 2 more views of your vision implemented in SketchUp in case
anyone would like to see:

http://web.newsguy.com/MySite/


Cool! I assume that the two wrong-way lights are the existing backups?


I had to move a few bit to accommodate obstacles (like garage door
opener). The luminaires with electronic ballasts featuring "instant
start" and less than 10% THD are about $40 each--lamps extra.


Total harmonic distortion in fluors? New one on me.


Wikipedia says 1% THD is supposed to be inaudible to the human ear.
"Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10% THD.

This is ALL sort of a "new one on me"! : ) FWIW, there is $14
difference in price between a track lights with Standard ballast
versus one with Instant Start ballast.

Bill
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On Thu, 02 Dec 2010 14:10:40 -0500, Bill
wrote:

On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, wrote:
I had to move a few bit to accommodate obstacles (like garage door
opener). The luminaires with electronic ballasts featuring "instant
start" and less than 10% THD are about $40 each--lamps extra.


Total harmonic distortion in fluors? New one on me.


Wikipedia says 1% THD is supposed to be inaudible to the human ear.
"Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10% THD.


So they're saying that these babies HUM LIKE HELL, or what?
WTF is an audio distortion figure doing on a light fixture?!?


This is ALL sort of a "new one on me"! : ) FWIW, there is $14
difference in price between a track lights with Standard ballast
versus one with Instant Start ballast.



--
"Human nature itself is evermore an advocate for liberty.
There is also in human nature a resentment of injury, and
indignation against wrong. A love of truth and a veneration
of virtue. These amiable passions, are the latent spark. If
the people are capable of understanding, seeing and feeling
the differences between true and false, right and wrong,
virtue and vice, to what better principle can the friends of
mankind apply than to the sense of this difference?"
--John Adams
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On 12/2/2010 9:35 AM, Mike Marlow wrote:
It's better to just stick with one kind of wiring as much as
possible. If conduit proves to be the best solution for the most of the
run, then go with it all the way on that circuit. In Bill's case - from the
switchbox throughout the lighting run - or at least to a minimum number of
J-boxes in which to switch over to NM, assuming the required protection for
NM.


Mike, Those words were not wasted on me.

Thanks,
Bill
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On Thu, 2 Dec 2010 14:21:02 -0500, "Mike Marlow"
wrote:

wrote:


When Dad, an electrician, had to do it he pulled the wire through the
conduit before installing it - goes through the bends and LBs a lot
easier that way. Using stranded wire involves junction boxes and
joints when transitioning from "protected by conduit" to "not
requiring protection" or "protected by existing structure"



You are quite correct in that, but it's not a big deal to hang the boxes and
tie in inside them. Using THHN offers many advantages over pulling NM
through conduit, and makes the transition matter of little real value.

Residential electriciand don't usually have rolls of individual wire
on the truck as (at least here in Ontario) it is VERY seldom used -
and was used even less back before Dad retired.


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wrote:
On Thu, 2 Dec 2010 14:21:02 -0500, "Mike Marlow"
wrote:

wrote:


When Dad, an electrician, had to do it he pulled the wire through
the conduit before installing it - goes through the bends and LBs a
lot easier that way. Using stranded wire involves junction boxes and
joints when transitioning from "protected by conduit" to "not
requiring protection" or "protected by existing structure"



You are quite correct in that, but it's not a big deal to hang the
boxes and tie in inside them. Using THHN offers many advantages
over pulling NM through conduit, and makes the transition matter of
little real value.


Residential electriciand don't usually have rolls of individual wire
on the truck as (at least here in Ontario) it is VERY seldom used -
and was used even less back before Dad retired.


I'd be surprised if residential electricians did not have THHN on the truck.
There are times and places for it even in residential wiring. If they
don't - Home Depot is just down the road. I'll agree that it is not a
significant percentage of residential wiring, but it's not at all an
uncommon occurrance, either. No matter - for the job at hand, any
residential electrician would not find it unreasonable to use conduit and
THHN in a given application. I don't know when your dad retired, but I've
been wiring for over 25 years, and I'm way older than that implies, and I've
seen plenty of conduit with stranded wire that pre-dates my arrival on
earth.

--

-Mike-



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On Dec 2, 3:47*pm, Larry Jaques wrote:
On Thu, 02 Dec 2010 14:10:40 -0500, Bill
wrote:

On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, *wrote:
I had to move a few bit to accommodate obstacles (like garage door
opener). *The luminaires with electronic ballasts featuring "instant
start" and less than 10% THD are about $40 each--lamps extra.


Total harmonic distortion in fluors? *New one on me.


Wikipedia says 1% THD is supposed to be inaudible to the human ear.
"Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10% THD.


So they're saying that these babies HUM LIKE HELL, or what?
WTF is an audio distortion figure doing on a light fixture?!?



Don't get me started. THD is a useless spec. It 's like a single
number indicating impurities in ice cream. Some impurities are straw,
some are bat ****.

'Even order' harmonics are much easier to put up with than 'odd
order' (not related to the fundamental note) harmonics. (Please, all
you musicians and psycho-acousticians keep your shirts on, I know it
is an over simplification.)
Even order harmonics is how we tell instruments apart, odd order
is ..is.. like..Celine Dijon (without AutoTune.)
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On Thu, 2 Dec 2010 14:36:55 -0800 (PST), Robatoy
wrote:

On Dec 2, 3:47*pm, Larry Jaques wrote:
On Thu, 02 Dec 2010 14:10:40 -0500, Bill
wrote:

On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, *wrote:
I had to move a few bit to accommodate obstacles (like garage door
opener). *The luminaires with electronic ballasts featuring "instant
start" and less than 10% THD are about $40 each--lamps extra.


Total harmonic distortion in fluors? *New one on me.


Wikipedia says 1% THD is supposed to be inaudible to the human ear.
"Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10% THD.


So they're saying that these babies HUM LIKE HELL, or what?
WTF is an audio distortion figure doing on a light fixture?!?



Don't get me started. THD is a useless spec. It 's like a single
number indicating impurities in ice cream. Some impurities are straw,
some are bat ****.


What _I_ want to know is if the phases are linear in my light
fixtures. Dat's impotent!


'Even order' harmonics are much easier to put up with than 'odd
order' (not related to the fundamental note) harmonics. (Please, all
you musicians and psycho-acousticians keep your shirts on, I know it
is an over simplification.)
Even order harmonics is how we tell instruments apart, odd order
is ..is.. like..Celine Dijon (without AutoTune.)


I think I prefer a 60 cycle hum to Dijon.

--
"Human nature itself is evermore an advocate for liberty.
There is also in human nature a resentment of injury, and
indignation against wrong. A love of truth and a veneration
of virtue. These amiable passions, are the latent spark. If
the people are capable of understanding, seeing and feeling
the differences between true and false, right and wrong,
virtue and vice, to what better principle can the friends of
mankind apply than to the sense of this difference?"
--John Adams
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On Thu, 2 Dec 2010 16:44:29 -0500, "Mike Marlow"
wrote:

wrote:
On Thu, 2 Dec 2010 14:21:02 -0500, "Mike Marlow"
wrote:

wrote:


When Dad, an electrician, had to do it he pulled the wire through
the conduit before installing it - goes through the bends and LBs a
lot easier that way. Using stranded wire involves junction boxes and
joints when transitioning from "protected by conduit" to "not
requiring protection" or "protected by existing structure"


You are quite correct in that, but it's not a big deal to hang the
boxes and tie in inside them. Using THHN offers many advantages
over pulling NM through conduit, and makes the transition matter of
little real value.


Residential electriciand don't usually have rolls of individual wire
on the truck as (at least here in Ontario) it is VERY seldom used -
and was used even less back before Dad retired.


I'd be surprised if residential electricians did not have THHN on the truck.
There are times and places for it even in residential wiring. If they
don't - Home Depot is just down the road. I'll agree that it is not a
significant percentage of residential wiring, but it's not at all an
uncommon occurrance, either. No matter - for the job at hand, any
residential electrician would not find it unreasonable to use conduit and
THHN in a given application. I don't know when your dad retired, but I've
been wiring for over 25 years, and I'm way older than that implies, and I've
seen plenty of conduit with stranded wire that pre-dates my arrival on
earth.


Pop is 82 next week. He retired when Mom died - that's 20 years ago
now.
Here in Ontario, very little conduit was/is used in residential other
than main power feeds. Not much 12 or 14 guage undividual cable, and
less yet in stranded (flexible) wire that small.

The main use of conduit was protection on concrete basement walls,
where the junction box would be inaccessible if a cieling was
installed, making an illegal concealed junction.
Running romex directly into the EMT strapped to the wall eliminated
the connection, making it fully code compliant, and legal. (even if
the cable entered the conduit through a box - as long as there were no
connections in the box)

Of course, if there was an issue with pulling the romex, the sheath
could be stripped off, producing separate conductors to pull through
the conduit. - again with no connections in the box.
Impractical for mor than 6 or 8 feet
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On Thu, 2 Dec 2010 14:36:55 -0800 (PST), Robatoy
wrote:

On Dec 2, 3:47Â*pm, Larry Jaques wrote:
On Thu, 02 Dec 2010 14:10:40 -0500, Bill
wrote:

On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, Â*wrote:
I had to move a few bit to accommodate obstacles (like garage door
opener). Â*The luminaires with electronic ballasts featuring "instant
start" and less than 10% THD are about $40 each--lamps extra.


Total harmonic distortion in fluors? Â*New one on me.


Wikipedia says 1% THD is supposed to be inaudible to the human ear.
"Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10% THD.


So they're saying that these babies HUM LIKE HELL, or what?
WTF is an audio distortion figure doing on a light fixture?!?



Don't get me started. THD is a useless spec. It 's like a single
number indicating impurities in ice cream. Some impurities are straw,
some are bat ****.

'Even order' harmonics are much easier to put up with than 'odd
order' (not related to the fundamental note) harmonics. (Please, all
you musicians and psycho-acousticians keep your shirts on, I know it
is an over simplification.)
Even order harmonics is how we tell instruments apart, odd order
is ..is.. like..Celine Dijon (without AutoTune.)



THD is not so much about accoustics as it is about "dirty power".
Low TDH ballasts are becoming much more common in
industrial/commercial lighting applications (specifically those with 3
phase power)

according to ITS Intertek Testing Services (Boxborough, MA)

Power line harmonics is just one of the many power quality issues that
arise with public utilities. Effectively, current harmonics represent
a distortion of the normal sine wave provided by the utility. When a
product such as an SCR switched load or a switching power supply
distorts the current, harmonics at multiples of the power line
frequency are generated. Two significant consequences arise as a
result of harmonic generation. First, because of finite impedances of
power lines, voltage variations are generated that other equipment on
the line must tolerate. Second, when generated in a three-phase
system, harmonics may cause overheating of neutral lines.

Power line harmonics are generated when a load draws a non-linear
current from a sinusoidal voltage. The harmonic component is an
element of a Fourier series which can be used to define any periodic
waveshape. The harmonic order or number is the integral number defined
by the ratio of the frequency of the harmonic to the fundamental
frequency (e.g., 150 Hz is the third harmonic of 50 Hz; n = 150/50). A
second harmonic is therefore two times the fundamental frequency of
the supply line volt current. If the supply voltage had been generated
by an ideal source (zero impedance), the current distortion would have
little effect on the supply voltage sine wave. However, because a
power system has a finite impedance, the current distortion caused by
a nonlinear load creates a corresponding voltage distortion in the
supply lines. This voltage distortion can subsequently disrupt
operation of other sensitive equipment connected to the same line.
Voltage distortion can also cause motors operating on the line to
overheat




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wrote:
On Thu, 2 Dec 2010 14:36:55 -0800 (PST), Robatoy
wrote:

On Dec 2, 3:47 pm, Larry wrote:
On Thu, 02 Dec 2010 14:10:40 -0500,
wrote:

On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, wrote:
I had to move a few bit to accommodate obstacles (like garage door
opener). The luminaires with electronic ballasts featuring "instant
start" and less than 10% THD are about $40 each--lamps extra.

Total harmonic distortion in fluors? New one on me.

Wikipedia says 1% THD is supposed to be inaudible to the human ear.
"Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10% THD.

So they're saying that these babies HUM LIKE HELL, or what?
WTF is an audio distortion figure doing on a light fixture?!?



Don't get me started. THD is a useless spec. It 's like a single
number indicating impurities in ice cream. Some impurities are straw,
some are bat ****.

'Even order' harmonics are much easier to put up with than 'odd
order' (not related to the fundamental note) harmonics. (Please, all
you musicians and psycho-acousticians keep your shirts on, I know it
is an over simplification.)
Even order harmonics is how we tell instruments apart, odd order
is ..is.. like..Celine Dijon (without AutoTune.)



THD is not so much about accoustics as it is about "dirty power".
Low TDH ballasts are becoming much more common in
industrial/commercial lighting applications (specifically those with 3
phase power)

according to ITS Intertek Testing Services (Boxborough, MA)

Power line harmonics is just one of the many power quality issues that
arise with public utilities. Effectively, current harmonics represent
a distortion of the normal sine wave provided by the utility. When a
product such as an SCR switched load or a switching power supply
distorts the current, harmonics at multiples of the power line
frequency are generated. Two significant consequences arise as a
result of harmonic generation. First, because of finite impedances of
power lines, voltage variations are generated that other equipment on
the line must tolerate. Second, when generated in a three-phase
system, harmonics may cause overheating of neutral lines.

Power line harmonics are generated when a load draws a non-linear
current from a sinusoidal voltage. The harmonic component is an
element of a Fourier series which can be used to define any periodic
waveshape. The harmonic order or number is the integral number defined
by the ratio of the frequency of the harmonic to the fundamental
frequency (e.g., 150 Hz is the third harmonic of 50 Hz; n = 150/50). A
second harmonic is therefore two times the fundamental frequency of
the supply line volt current. If the supply voltage had been generated
by an ideal source (zero impedance), the current distortion would have
little effect on the supply voltage sine wave. However, because a
power system has a finite impedance, the current distortion caused by
a nonlinear load creates a corresponding voltage distortion in the
supply lines. This voltage distortion can subsequently disrupt
operation of other sensitive equipment connected to the same line.
Voltage distortion can also cause motors operating on the line to
overheat


The only thing I can add to that is that really high THD can cause a
fire (really)!

Bill


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On Thu, 02 Dec 2010 21:00:13 -0500, Bill wrote:

wrote:
On Thu, 2 Dec 2010 14:36:55 -0800 (PST), Robatoy
wrote:

On Dec 2, 3:47 pm, Larry wrote:
On Thu, 02 Dec 2010 14:10:40 -0500,
wrote:

On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, wrote:
I had to move a few bit to accommodate obstacles (like garage door
opener). The luminaires with electronic ballasts featuring "instant
start" and less than 10% THD are about $40 each--lamps extra.

Total harmonic distortion in fluors? New one on me.

Wikipedia says 1% THD is supposed to be inaudible to the human ear.
"Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10% THD.

So they're saying that these babies HUM LIKE HELL, or what?
WTF is an audio distortion figure doing on a light fixture?!?


Don't get me started. THD is a useless spec. It 's like a single
number indicating impurities in ice cream. Some impurities are straw,
some are bat ****.

'Even order' harmonics are much easier to put up with than 'odd
order' (not related to the fundamental note) harmonics. (Please, all
you musicians and psycho-acousticians keep your shirts on, I know it
is an over simplification.)
Even order harmonics is how we tell instruments apart, odd order
is ..is.. like..Celine Dijon (without AutoTune.)



THD is not so much about accoustics as it is about "dirty power".
Low TDH ballasts are becoming much more common in
industrial/commercial lighting applications (specifically those with 3
phase power)

according to ITS Intertek Testing Services (Boxborough, MA)

Power line harmonics is just one of the many power quality issues that
arise with public utilities. Effectively, current harmonics represent
a distortion of the normal sine wave provided by the utility. When a
product such as an SCR switched load or a switching power supply
distorts the current, harmonics at multiples of the power line
frequency are generated. Two significant consequences arise as a
result of harmonic generation. First, because of finite impedances of
power lines, voltage variations are generated that other equipment on
the line must tolerate. Second, when generated in a three-phase
system, harmonics may cause overheating of neutral lines.

Power line harmonics are generated when a load draws a non-linear
current from a sinusoidal voltage. The harmonic component is an
element of a Fourier series which can be used to define any periodic
waveshape. The harmonic order or number is the integral number defined
by the ratio of the frequency of the harmonic to the fundamental
frequency (e.g., 150 Hz is the third harmonic of 50 Hz; n = 150/50). A
second harmonic is therefore two times the fundamental frequency of
the supply line volt current. If the supply voltage had been generated
by an ideal source (zero impedance), the current distortion would have
little effect on the supply voltage sine wave. However, because a
power system has a finite impedance, the current distortion caused by
a nonlinear load creates a corresponding voltage distortion in the
supply lines. This voltage distortion can subsequently disrupt
operation of other sensitive equipment connected to the same line.
Voltage distortion can also cause motors operating on the line to
overheat


The only thing I can add to that is that really high THD can cause a
fire (really)!

Bill

Yes, on 3 phase supplies due to overloading of the unprotected
(unfused) neutral due to triplen harmonics
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wrote:
On Thu, 2 Dec 2010 16:44:29 -0500, "Mike Marlow"
wrote:

wrote:
On Thu, 2 Dec 2010 14:21:02 -0500, "Mike Marlow"
wrote:

wrote:


When Dad, an electrician, had to do it he pulled the wire through
the conduit before installing it - goes through the bends and LBs
a lot easier that way. Using stranded wire involves junction
boxes and joints when transitioning from "protected by conduit"
to "not requiring protection" or "protected by existing structure"


You are quite correct in that, but it's not a big deal to hang the
boxes and tie in inside them. Using THHN offers many advantages
over pulling NM through conduit, and makes the transition matter of
little real value.


Residential electriciand don't usually have rolls of individual wire
on the truck as (at least here in Ontario) it is VERY seldom used -
and was used even less back before Dad retired.


I'd be surprised if residential electricians did not have THHN on
the truck. There are times and places for it even in residential
wiring. If they don't - Home Depot is just down the road. I'll
agree that it is not a significant percentage of residential wiring,
but it's not at all an uncommon occurrance, either. No matter - for
the job at hand, any residential electrician would not find it
unreasonable to use conduit and THHN in a given application. I
don't know when your dad retired, but I've been wiring for over 25
years, and I'm way older than that implies, and I've seen plenty of
conduit with stranded wire that pre-dates my arrival on earth.


Pop is 82 next week. He retired when Mom died - that's 20 years ago
now.
Here in Ontario, very little conduit was/is used in residential other
than main power feeds. Not much 12 or 14 guage undividual cable, and
less yet in stranded (flexible) wire that small.

The main use of conduit was protection on concrete basement walls,
where the junction box would be inaccessible if a cieling was
installed, making an illegal concealed junction.
Running romex directly into the EMT strapped to the wall eliminated
the connection, making it fully code compliant, and legal. (even if
the cable entered the conduit through a box - as long as there were no
connections in the box)

Of course, if there was an issue with pulling the romex, the sheath
could be stripped off, producing separate conductors to pull through
the conduit. - again with no connections in the box.
Impractical for mor than 6 or 8 feet


I have to say, regardless of whether we get to any further point of
understanding on this little piece of this thread, I am finding that I am
enjoying your posts in this thread. I'm enjoying the way your talk about
"dad", "mom", etc. Screw all the other details - I'm just enjoying reading
your responses. That probably does nothing to advance this thread, but I
don't really care. Just enjoying what you're writing.


--

-Mike-



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Bill wrote:
wrote:
On Thu, 2 Dec 2010 14:36:55 -0800 (PST), Robatoy
wrote:

On Dec 2, 3:47 pm, Larry wrote:
On Thu, 02 Dec 2010 14:10:40 -0500,
wrote:

On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, wrote:
I had to move a few bit to accommodate obstacles (like garage
door opener). The luminaires with electronic ballasts
featuring "instant start" and less than 10% THD are about $40
each--lamps extra.

Total harmonic distortion in fluors? New one on me.

Wikipedia says 1% THD is supposed to be inaudible to the human
ear. "Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10%
THD.

So they're saying that these babies HUM LIKE HELL, or what?
WTF is an audio distortion figure doing on a light fixture?!?


Don't get me started. THD is a useless spec. It 's like a single
number indicating impurities in ice cream. Some impurities are
straw, some are bat ****.

'Even order' harmonics are much easier to put up with than 'odd
order' (not related to the fundamental note) harmonics. (Please, all
you musicians and psycho-acousticians keep your shirts on, I know it
is an over simplification.)
Even order harmonics is how we tell instruments apart, odd order
is ..is.. like..Celine Dijon (without AutoTune.)



THD is not so much about accoustics as it is about "dirty power".
Low TDH ballasts are becoming much more common in
industrial/commercial lighting applications (specifically those with
3 phase power)

according to ITS Intertek Testing Services (Boxborough, MA)

Power line harmonics is just one of the many power quality issues
that arise with public utilities. Effectively, current harmonics
represent a distortion of the normal sine wave provided by the
utility. When a product such as an SCR switched load or a switching
power supply distorts the current, harmonics at multiples of the
power line frequency are generated. Two significant consequences
arise as a result of harmonic generation. First, because of finite
impedances of power lines, voltage variations are generated that
other equipment on the line must tolerate. Second, when generated in
a three-phase system, harmonics may cause overheating of neutral
lines. Power line harmonics are generated when a load draws a non-linear
current from a sinusoidal voltage. The harmonic component is an
element of a Fourier series which can be used to define any periodic
waveshape. The harmonic order or number is the integral number
defined by the ratio of the frequency of the harmonic to the
fundamental frequency (e.g., 150 Hz is the third harmonic of 50 Hz;
n = 150/50). A second harmonic is therefore two times the
fundamental frequency of the supply line volt current. If the supply
voltage had been generated by an ideal source (zero impedance), the
current distortion would have little effect on the supply voltage
sine wave. However, because a power system has a finite impedance,
the current distortion caused by a nonlinear load creates a
corresponding voltage distortion in the supply lines. This voltage
distortion can subsequently disrupt operation of other sensitive
equipment connected to the same line. Voltage distortion can also
cause motors operating on the line to overheat


The only thing I can add to that is that really high THD can cause a
fire (really)!

Bill


You guys are all really screwed up. Please explain to me how a really high
The Home Depot can cause any of these concerns. Boy, sometimes...

--

-Mike-



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On 12/02/10 10:08 PM, Mike Marlow wrote:
Bill wrote:
wrote:
On Thu, 2 Dec 2010 14:36:55 -0800 (PST), Robatoy
wrote:

On Dec 2, 3:47 pm, Larry wrote:
On Thu, 02 Dec 2010 14:10:40 -0500,
wrote:

On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, wrote:
I had to move a few bit to accommodate obstacles (like garage
door opener). The luminaires with electronic ballasts
featuring "instant start" and less than 10% THD are about $40
each--lamps extra.

Total harmonic distortion in fluors? New one on me.

Wikipedia says 1% THD is supposed to be inaudible to the human
ear. "Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10%
THD.

So they're saying that these babies HUM LIKE HELL, or what?
WTF is an audio distortion figure doing on a light fixture?!?


Don't get me started. THD is a useless spec. It 's like a single
number indicating impurities in ice cream. Some impurities are
straw, some are bat ****.

'Even order' harmonics are much easier to put up with than 'odd
order' (not related to the fundamental note) harmonics. (Please, all
you musicians and psycho-acousticians keep your shirts on, I know it
is an over simplification.)
Even order harmonics is how we tell instruments apart, odd order
is ..is.. like..Celine Dijon (without AutoTune.)


THD is not so much about accoustics as it is about "dirty power".
Low TDH ballasts are becoming much more common in
industrial/commercial lighting applications (specifically those with
3 phase power)

according to ITS Intertek Testing Services (Boxborough, MA)

Power line harmonics is just one of the many power quality issues
that arise with public utilities. Effectively, current harmonics
represent a distortion of the normal sine wave provided by the
utility. When a product such as an SCR switched load or a switching
power supply distorts the current, harmonics at multiples of the
power line frequency are generated. Two significant consequences
arise as a result of harmonic generation. First, because of finite
impedances of power lines, voltage variations are generated that
other equipment on the line must tolerate. Second, when generated in
a three-phase system, harmonics may cause overheating of neutral
lines. Power line harmonics are generated when a load draws a non-linear
current from a sinusoidal voltage. The harmonic component is an
element of a Fourier series which can be used to define any periodic
waveshape. The harmonic order or number is the integral number
defined by the ratio of the frequency of the harmonic to the
fundamental frequency (e.g., 150 Hz is the third harmonic of 50 Hz;
n = 150/50). A second harmonic is therefore two times the
fundamental frequency of the supply line volt current. If the supply
voltage had been generated by an ideal source (zero impedance), the
current distortion would have little effect on the supply voltage
sine wave. However, because a power system has a finite impedance,
the current distortion caused by a nonlinear load creates a
corresponding voltage distortion in the supply lines. This voltage
distortion can subsequently disrupt operation of other sensitive
equipment connected to the same line. Voltage distortion can also
cause motors operating on the line to overheat


The only thing I can add to that is that really high THD can cause a
fire (really)!

Bill


You guys are all really screwed up. Please explain to me how a really high
The Home Depot can cause any of these concerns. Boy, sometimes...

You haven't seen some of the really high Hope Depot employees?

--
Froz...


The system will be down for 10 days for preventive maintenance.


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On Thu, 2 Dec 2010 22:05:52 -0500, "Mike Marlow"
wrote:

wrote:
On Thu, 2 Dec 2010 16:44:29 -0500, "Mike Marlow"
wrote:

wrote:
On Thu, 2 Dec 2010 14:21:02 -0500, "Mike Marlow"
wrote:

wrote:


When Dad, an electrician, had to do it he pulled the wire through
the conduit before installing it - goes through the bends and LBs
a lot easier that way. Using stranded wire involves junction
boxes and joints when transitioning from "protected by conduit"
to "not requiring protection" or "protected by existing structure"


You are quite correct in that, but it's not a big deal to hang the
boxes and tie in inside them. Using THHN offers many advantages
over pulling NM through conduit, and makes the transition matter of
little real value.

Residential electriciand don't usually have rolls of individual wire
on the truck as (at least here in Ontario) it is VERY seldom used -
and was used even less back before Dad retired.

I'd be surprised if residential electricians did not have THHN on
the truck. There are times and places for it even in residential
wiring. If they don't - Home Depot is just down the road. I'll
agree that it is not a significant percentage of residential wiring,
but it's not at all an uncommon occurrance, either. No matter - for
the job at hand, any residential electrician would not find it
unreasonable to use conduit and THHN in a given application. I
don't know when your dad retired, but I've been wiring for over 25
years, and I'm way older than that implies, and I've seen plenty of
conduit with stranded wire that pre-dates my arrival on earth.


Pop is 82 next week. He retired when Mom died - that's 20 years ago
now.
Here in Ontario, very little conduit was/is used in residential other
than main power feeds. Not much 12 or 14 guage undividual cable, and
less yet in stranded (flexible) wire that small.

The main use of conduit was protection on concrete basement walls,
where the junction box would be inaccessible if a cieling was
installed, making an illegal concealed junction.
Running romex directly into the EMT strapped to the wall eliminated
the connection, making it fully code compliant, and legal. (even if
the cable entered the conduit through a box - as long as there were no
connections in the box)

Of course, if there was an issue with pulling the romex, the sheath
could be stripped off, producing separate conductors to pull through
the conduit. - again with no connections in the box.
Impractical for mor than 6 or 8 feet


I have to say, regardless of whether we get to any further point of
understanding on this little piece of this thread, I am finding that I am
enjoying your posts in this thread. I'm enjoying the way your talk about
"dad", "mom", etc. Screw all the other details - I'm just enjoying reading
your responses. That probably does nothing to advance this thread, but I
don't really care. Just enjoying what you're writing.

Thanks,
We lost Mom way too young. 3 months before her 63rd birthday, 2 years,
almost to the day, after her breast cancer diagnosis. Same age my good
wife is now - - -
Dad remarried - gal with 12 kids who lost her husband to leukemia.
Added to his 8, there were lots of kids and grandkids to keep him
occupied. She died 5 years later, also of cancer, and a few of her
kids made it pretty rough on Dad. He still stays in contact with a
few, and has been married 10 years to his third wife - his "unclaimed
jewel" - no encumberances in the way of kids, exes, etc.
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FrozenNorth wrote:
On 12/02/10 10:08 PM, Mike Marlow wrote:


You guys are all really screwed up. Please explain to me how a
really high The Home Depot can cause any of these concerns. Boy,
sometimes...

You haven't seen some of the really high Hope Depot employees?


You have to get THD in there. (The Home Depot...)
xis


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On Thu, 02 Dec 2010 19:33:27 -0500, wrote:

On Thu, 2 Dec 2010 14:36:55 -0800 (PST), Robatoy
wrote:

On Dec 2, 3:47*pm, Larry Jaques wrote:
On Thu, 02 Dec 2010 14:10:40 -0500, Bill
wrote:

On 12/2/2010 8:23 AM, Larry Jaques wrote:
On Thu, 02 Dec 2010 02:02:06 -0500, *wrote:
I had to move a few bit to accommodate obstacles (like garage door
opener). *The luminaires with electronic ballasts featuring "instant
start" and less than 10% THD are about $40 each--lamps extra.

Total harmonic distortion in fluors? *New one on me.

Wikipedia says 1% THD is supposed to be inaudible to the human ear.
"Standard" (Lithonia) electronic ballasts are 20% THD
"Instant on and Rapid start" electronic ballast by Lithonia are 10% THD.

So they're saying that these babies HUM LIKE HELL, or what?
WTF is an audio distortion figure doing on a light fixture?!?



Don't get me started. THD is a useless spec. It 's like a single
number indicating impurities in ice cream. Some impurities are straw,
some are bat ****.

'Even order' harmonics are much easier to put up with than 'odd
order' (not related to the fundamental note) harmonics. (Please, all
you musicians and psycho-acousticians keep your shirts on, I know it
is an over simplification.)
Even order harmonics is how we tell instruments apart, odd order
is ..is.. like..Celine Dijon (without AutoTune.)



THD is not so much about accoustics as it is about "dirty power".
Low TDH ballasts are becoming much more common in
industrial/commercial lighting applications (specifically those with 3
phase power)

according to ITS Intertek Testing Services (Boxborough, MA)

Power line harmonics is just one of the many power quality issues that
arise with public utilities.


Major understatement. Talk about dirty power nowadays...


Effectively, current harmonics represent
a distortion of the normal sine wave provided by the utility. When a
product such as an SCR switched load or a switching power supply
distorts the current, harmonics at multiples of the power line
frequency are generated. Two significant consequences arise as a
result of harmonic generation. First, because of finite impedances of
power lines, voltage variations are generated that other equipment on
the line must tolerate. Second, when generated in a three-phase
system, harmonics may cause overheating of neutral lines.


So, how much of this affects the generation of clean light in fluor
instances, generally on 120v single phase systems?


Power line harmonics are generated when a load draws a non-linear
current from a sinusoidal voltage. The harmonic component is an
element of a Fourier series which can be used to define any periodic
waveshape. The harmonic order or number is the integral number defined
by the ratio of the frequency of the harmonic to the fundamental
frequency (e.g., 150 Hz is the third harmonic of 50 Hz; n = 150/50). A
second harmonic is therefore two times the fundamental frequency of
the supply line volt current. If the supply voltage had been generated
by an ideal source (zero impedance), the current distortion would have
little effect on the supply voltage sine wave. However, because a
power system has a finite impedance, the current distortion caused by
a nonlinear load creates a corresponding voltage distortion in the
supply lines. This voltage distortion can subsequently disrupt
operation of other sensitive equipment connected to the same line.
Voltage distortion can also cause motors operating on the line to
overheat


Thanks, clare. That will certainly trump any answer I get from my
request about the subject in an email to Lithonia.

--
"Human nature itself is evermore an advocate for liberty.
There is also in human nature a resentment of injury, and
indignation against wrong. A love of truth and a veneration
of virtue. These amiable passions, are the latent spark. If
the people are capable of understanding, seeing and feeling
the differences between true and false, right and wrong,
virtue and vice, to what better principle can the friends of
mankind apply than to the sense of this difference?"
--John Adams
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On Thu, 2 Dec 2010 22:46:01 -0500, "Mike Marlow"
wrote:

wrote:

Thanks,
We lost Mom way too young. 3 months before her 63rd birthday, 2 years,
almost to the day, after her breast cancer diagnosis. Same age my good
wife is now - - -
Dad remarried - gal with 12 kids who lost her husband to leukemia.
Added to his 8, there were lots of kids and grandkids to keep him
occupied. She died 5 years later, also of cancer, and a few of her
kids made it pretty rough on Dad. He still stays in contact with a
few, and has been married 10 years to his third wife - his "unclaimed
jewel" - no encumberances in the way of kids, exes, etc.


You gotta have a talk with your dad...



Rather a wife looking after him than me having to.
The one he's got now is another "keeper" and something like 6 years
younger than him.


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On Thu, 02 Dec 2010 19:54:01 -0800, Larry Jaques
wrote:


So, how much of this affects the generation of clean light in fluor
instances, generally on 120v single phase systems?


For all you ever wanted to know about power line harmonics, go to:
http://ewh.ieee.org/conf/tdc/elimina...t_Problems.pdf

The problem is also very real in single phase distribution systems
(120/240). The flourescent ballasts are electronic, just like the
computer power supplies referenced in the above-mentioned article.

The harmonics can be REALLY nasty.
Which is why, for computers (particularly servers and high power
workstations), I STRONGLY recommend DUAL CONVERSION UPS units - which
totally decouple the harmonics from the power line, and vise versa.

Power line harmonics are generated when a load draws a non-linear
current from a sinusoidal voltage. The harmonic component is an
element of a Fourier series which can be used to define any periodic
waveshape. The harmonic order or number is the integral number defined
by the ratio of the frequency of the harmonic to the fundamental
frequency (e.g., 150 Hz is the third harmonic of 50 Hz; n = 150/50). A
second harmonic is therefore two times the fundamental frequency of
the supply line volt current. If the supply voltage had been generated
by an ideal source (zero impedance), the current distortion would have
little effect on the supply voltage sine wave. However, because a
power system has a finite impedance, the current distortion caused by
a nonlinear load creates a corresponding voltage distortion in the
supply lines. This voltage distortion can subsequently disrupt
operation of other sensitive equipment connected to the same line.
Voltage distortion can also cause motors operating on the line to
overheat


Thanks, clare. That will certainly trump any answer I get from my
request about the subject in an email to Lithonia.


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Subject

It is absolutely amazing all the B/S to relight a 2 car garage, quasi
whore house (stippled ceiling), maybe workshop.

Close to 100 posts, most totally crap.

IES recommendations for a machine shop/wood shop call for 100 foot
candles maintained.

Using 2 lamp fixtures, approximately 19 fixtures are required for 100
FC maintained.

Given the geometry of the room and fixtures, 19 fixtures would be
difficult to maccomplish.

16 fixtures gives a good fit and still provides 71-72 FC maintained.

Run 1 x 4 x 24 ft furring strips equally spaced on 5 ft centers,
nailing or screwing thru drywall into ceiling joists. (4 runs)

Prime and paint when finished to match whore house ceiling.

(Since these furring strips are 30" from the side wall, they will miss
the overhead garage door tracks by at least 12" on each side.)

Mount 4 fixtures directly to furring strips with screws on 5 ft
centers leaving 2-1/2 space at beginning and end of runs and 12"
between for the 3/4" EMT.

Install 1 ft lengths of 3/4 EMT (Thin Wall Conduit) between fixtures.

Pull 12-3 /W/ ground THHN (Blk, Red, White, Green) for each run (L1,
L2, N, G).

Stagger fixture wiring as follows:

Row 1: L1, L2, L1, L2
Row 2: L2, L1, L2, L1
Row 3: L1, L2, L1, L2
Row 4: L2, L1, L2, L1

The above uses two (2), 1P-20A c'bkrs and provides two levels of
lighting, 50% & 100%.

At this point, two (2) wall switches can be added so the c'bkrs do not
have to be cycled.

Don't sweat covering fixtures with the garage door.

At most, two (2) fixtures get covered, but you still get some diffused
light from them.

Enough bull **** already.

Spend a few bucks, you can't take it with you.

Time for the next job.

Lew


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On Thu, 2 Dec 2010 20:25:52 -0800, "Lew Hodgett"
wrote:

Subject

It is absolutely amazing all the B/S to relight a 2 car garage, quasi
whore house (stippled ceiling), maybe workshop.


He called it a stippled ceiling - my best guess is it is rough-coat,
or sand-coat plaster. My whole garage is finished that way. Ceiling
and walls.

I'd pretty well agree with the rest.
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Mike Marlow wrote:
FrozenNorth wrote:
On 12/02/10 10:08 PM, Mike Marlow wrote:


You guys are all really screwed up. Please explain to me how a
really high The Home Depot can cause any of these concerns. Boy,
sometimes...

You haven't seen some of the really high Hope Depot employees?


You have to get THD in there. (The Home Depot...)
xis



THA, THB, THC, THD ?

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On Thu, 02 Dec 2010 23:58:18 -0500, Bill wrote:

Mike Marlow wrote:
FrozenNorth wrote:
On 12/02/10 10:08 PM, Mike Marlow wrote:


You guys are all really screwed up. Please explain to me how a
really high The Home Depot can cause any of these concerns. Boy,
sometimes...
You haven't seen some of the really high Hope Depot employees?


You have to get THD in there. (The Home Depot...)
xis



THA, THB, THC, THD ?



Methinks a few guys on the list have had too much THC.


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"Lew Hodgett" wrote in message
b.com...
Subject

It is absolutely amazing all the B/S to relight a 2 car garage, quasi
whore house (stippled ceiling), maybe workshop.



I've only see a couple whore houses - overseas at that - but I don't recall
stippled ceilings. Is that common?

--
If your name is No, I voted for you - more than once ...

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Lobby Dosser wrote:
"Lew Hodgett" wrote in message
b.com...
Subject

It is absolutely amazing all the B/S to relight a 2 car garage, quasi
whore house (stippled ceiling), maybe workshop.



I've only see a couple whore houses - overseas at that - but I don't
recall stippled ceilings. Is that common?


Generally speaking - you wouldn't notice...

--

-Mike-



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On Thu, 2 Dec 2010 22:08:47 -0500, "Mike Marlow"
wrote:

Bill wrote:


The only thing I can add to that is that really high THD can cause a
fire (really)!


You guys are all really screwed up. Please explain to me how a really high
The Home Depot can cause any of these concerns. Boy, sometimes...


C'mon, Mike. THD stands for Theoretical Hormonal Discharge and has
nothing to do with Homey's Despot stores or their empl...er, stores.

--
"Human nature itself is evermore an advocate for liberty.
There is also in human nature a resentment of injury, and
indignation against wrong. A love of truth and a veneration
of virtue. These amiable passions, are the latent spark. If
the people are capable of understanding, seeing and feeling
the differences between true and false, right and wrong,
virtue and vice, to what better principle can the friends of
mankind apply than to the sense of this difference?"
--John Adams
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Larry Jaques wrote:
On Thu, 2 Dec 2010 22:08:47 -0500, "Mike Marlow"
wrote:

Bill wrote:


The only thing I can add to that is that really high THD can cause a
fire (really)!


You guys are all really screwed up. Please explain to me how a
really high The Home Depot can cause any of these concerns. Boy,
sometimes...


C'mon, Mike. THD stands for Theoretical Hormonal Discharge and has
nothing to do with Homey's Despot stores or their empl...er, stores.


There is nothing theoretical about Hormonal anything. Just ask any of us
with wives who are.... ummmmm, well, you know...

--

-Mike-



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On Thu, 02 Dec 2010 23:08:01 -0500, wrote:

On Thu, 02 Dec 2010 19:54:01 -0800, Larry Jaques
wrote:


So, how much of this affects the generation of clean light in fluor
instances, generally on 120v single phase systems?


For all you ever wanted to know about power line harmonics, go to:
http://ewh.ieee.org/conf/tdc/elimina...t_Problems.pdf

The problem is also very real in single phase distribution systems
(120/240). The flourescent ballasts are electronic, just like the
computer power supplies referenced in the above-mentioned article.


Tanks. Will peruse. Hmm, I didn't see any single phase info the first
time through.


The harmonics can be REALLY nasty.
Which is why, for computers (particularly servers and high power
workstations), I STRONGLY recommend DUAL CONVERSION UPS units - which
totally decouple the harmonics from the power line, and vise versa.


I've had a UPS on the computer since the early '90s, after losing the
best sales pitch I ever made to an instantaneous glitch which rebooted
my computer on me. I vowed that it would never happen again.

Are they really causing problems in fluor fixtures? I don't recall
ever having heard that before. Symptoms, besides fire?

--
"Human nature itself is evermore an advocate for liberty.
There is also in human nature a resentment of injury, and
indignation against wrong. A love of truth and a veneration
of virtue. These amiable passions, are the latent spark. If
the people are capable of understanding, seeing and feeling
the differences between true and false, right and wrong,
virtue and vice, to what better principle can the friends of
mankind apply than to the sense of this difference?"
--John Adams


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On Thu, 2 Dec 2010 20:25:52 -0800, "Lew Hodgett"
wrote:

Subject

It is absolutely amazing all the B/S to relight a 2 car garage, quasi
whore house (stippled ceiling), maybe workshop.

Close to 100 posts, most totally crap.

IES recommendations for a machine shop/wood shop call for 100 foot
candles maintained.

Using 2 lamp fixtures, approximately 19 fixtures are required for 100
FC maintained.


The future's so bright, I GOTTA WEAR SHADES.

--
"Human nature itself is evermore an advocate for liberty.
There is also in human nature a resentment of injury, and
indignation against wrong. A love of truth and a veneration
of virtue. These amiable passions, are the latent spark. If
the people are capable of understanding, seeing and feeling
the differences between true and false, right and wrong,
virtue and vice, to what better principle can the friends of
mankind apply than to the sense of this difference?"
--John Adams
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On Thu, 2 Dec 2010 22:08:47 -0500, "Mike Marlow"
wrote:

The only thing I can add to that is that really high THD can cause a
fire (really)!

Bill


You guys are all really screwed up. Please explain to me how a really high
The Home Depot can cause any of these concerns. Boy, sometimes...


Add in triboelectric current and boy.

Mark
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On Fri, 03 Dec 2010 07:56:28 -0800, Larry Jaques
wrote:

I've had a UPS on the computer since the early '90s, after losing the
best sales pitch I ever made to an instantaneous glitch which rebooted
my computer on me. I vowed that it would never happen again.

Are they really causing problems in fluor fixtures? I don't recall
ever having heard that before. Symptoms, besides fire?

A normal cheapy UPS doesn't help at all - it needs to be an "on-line"
or "dual conversion" UPS to do the job.

Google it.
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In article ,
Larry Jaques wrote:

Are they really causing problems in fluor fixtures?


Large installations get nasty-grams from the power company. That's rare
at the home installation scale, but not impossible. Depending how things
are coupled and designed, the (electrical) noise thrown off can affect
other systems that want or assume "clean" power. And (again, usually
more of an issue on large installations, or ones with load metering) you
can run into being limited on how many fixtures you can hang off a
circuit due to poor power factor (which goes along with high distortion)
causing the fixture's VA to be far larger than its wattage - and you
have to size the wiring for the VA.

In most home setups none of this matters enough to worry too much about,
but I'm still fairly confident that my 0.99 power factor GE replacement
ballasts really are better ballasts than the 0.5 PF ones that some of
the cheap lights I've bought have. From the right source, they don't
even cost much more. But trying to buy a fixture with a specific ballast
is a real pain in the wallet (or information that's not provided and
needs to be hunted down) much of the time.

Going back earlier in the thread, the electrical distortion has nearly
nothing to do with the audible noise a fixture may make. Look for an "A"
sound rating if that's your concern, and avoid the old-style magnetic
ballasts.

--
Cats, coffee, chocolate...vices to live by
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"Lew Hodgett" wrote

Close to 100 posts, most totally crap.

IES recommendations for a machine shop/wood shop call for 100 foot
candles maintained.

Using 2 lamp fixtures, approximately 19 fixtures are required for 100 FC
maintained.


I agree with the point that it is tough to get enough light for a shop.

I would say that he should check out the high output 8 foot fixtures,
though. It is amazing how much light they put out. It may be more
economical to go that way.
--
Jim in NC



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In article ,
"Morgans" wrote:

"Lew Hodgett" wrote

Close to 100 posts, most totally crap.

IES recommendations for a machine shop/wood shop call for 100 foot
candles maintained.

Using 2 lamp fixtures, approximately 19 fixtures are required for 100 FC
maintained.


I agree with the point that it is tough to get enough light for a shop.

I would say that he should check out the high output 8 foot fixtures,
though. It is amazing how much light they put out. It may be more
economical to go that way.


For a low ceiling, HO fixtures are dubious - hard to get the light
evenly distributed if there's only 5 feet or so between the fixture and
the bench-height. At about 10 feet and up they make more sense (but
stick with low bay fixtures until you get to 16 feet or more). For any
ceiling, 8 foot bulbs are a pain to transport, have shipped, etc. .vs. 4
foot bulbs, and don't offer much, if any, improvement in efficiency. You
can get a boat-load of light in a high-output 4 foot fixture, and get
bulbs shipped UPS...

--
Cats, coffee, chocolate...vices to live by
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Someone suggested (I could not locate the post) that if I wanted quiet
fluorescent lights, then I should look for those with an "A" rating.

Putting that detail aside temporarily. What would be the practical
differences between a "standard electronic ballast with 20 THD"
and an "instant on electronic ballast with 10 THD"?

Bill
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On 12/6/2010 10:50 AM, Bill wrote:
Someone suggested (I could not locate the post) that if I wanted quiet
fluorescent lights, then I should look for those with an "A" rating.

Putting that detail aside temporarily. What would be the practical
differences between a "standard electronic ballast with 20 THD"
and an "instant on electronic ballast with 10 THD"?

Bill


Trying, usually, to answer questions for myself before and after I post,
I ran across the following tidbit. It isn't that helpful though. BTW, I
have no reason to believe THD is accumulated if fixtures are wired in a
series, but I would certainly be interested in knowing if anything of
that nature is true.


THD stands for Total Harmonic Distortion. The distortion is feedback
caused by deviation from the sinusoidal waveform. The industry standard
is less than 20%. If the THD is very high (around 150%), an electrical
fire can occur. Magnetic ballast run 90%-120% THD.

The information above was copied from :
http://www.ace-ballast.com/articles/...last_Questions

Bill
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