Motion Sensor Light for Front Entrance

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My dad asked me to replace the light next to his front door with a
motion sensing unit. He bought a stock fixture from HD with the sensor
built into the fixture. There is no way to aim the sensor, it just
points straight out from the front of the fixture.

The instructions say that the sensor will work better if the "heat
source" moves across the coverage area as opposed to straight towards
it. They sure got that right!

The approach to their front door is straight up a ~40' walkway from
the sidewalk. Even set at the highest sensitivity, which should allow
for a ~30' range, the light doesn't come on until the person is right
at the stoop, ready to lift their leg onto the first step.

However, if you walk across the yard the light will come on anywhere
in the 5' to 30'+ range. In fact, 1 out 3 cars going down the street
activate the light.

Unfortunately, "across the coverage area" is not how they (or anyone
else) would approach their front door.

What kind of fixture/sensor does he need so that it will pick up
people walking straight towards it?

BTW, it's an old brick house with a shallow box for the fixture cut
into the brick. A one-for-one swap is easy, but mounting a separate
sensor someplace else and running wires back to the fixture would be a
pain. I'd really prefer something built into the fixture if possible.

Thanks!

Re: Motion Sensor Light for Front Entrance
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One alternative is to use X10.   These are electrical products that
communicate via the existing house wiring.   They have a motion sensor
that is wireless, operates on batteries, and can be mounted outdoors
anywhere.   So, you could mount it so that people will walk across in
front of it as they come up the sidewalk.

The wireless unit transmits a signal that is received by a small
module that you plug in to any nearby AC outlet in the house.   That
module puts the communication signal on the AC house wiring, where it
should be able to be picked up by any X10 device that is connected to
the AC wiring anywhere in the house.

So, the next part you need is an X10 wall switch.  It replaces a
standard wall switch and can be turned on/off manually like a regular
switch, or via the X10 AC signals.

So, when someone walks by, the wireless sends the turn-on signal to
the wireless receiver.  The receiver puts the signal on the AC line
and the switch receives it and turns the light on.

The motion sensor also has a light sensor, so it can be programmed to
always turn the light on at dusk, or to only turn it on after dusk if
motion is detected, etc.  You can also program how long it stays on
after motion is sensed.

The modules are cheap and can be found for under $10 on Ebay.  I put
one in for a friend recently similar to what you want to do.  The
motion sensor is located on the outside garage wall, so when you drive
up, it turns on the 3 lights outside the garage.   The same sensor
also sends a dusk signal to a switch that works the front door lights
on the other side of the house.   It turns those lightsm which are CFL
on at dusk and off at dawn.

Some caveats:

X10 is not always 100% reliable, but I've used it for this kind of
application and it works fine.  Also the outdoor module probably has a
life of a couple years, but then they only cost $10 and you can even
use double sided velcro tape to attache them.

Any of the X10 modules will work with incandescent bulbs.   If you
want to use CFL, you need to get a module that says it will work with
any loads.  For example, they have modules that are specd for
appliances, so they have a relay inside, as opposed to electronic
switching and will work with CFL.

As with any motion sensor, you can get false turn-on from moving
shrubs, etc.

Re: Motion Sensor Light for Front Entrance
On Sep 7, 11:11=A0am, trad...@optonline.net wrote:
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Thanks. I'll look into it.

The fixture dad bought has all of the dusk-to-dawn, timer, etc.
features that you mentioned, which is what he wanted, so that's good.

re: "The next part you need is an X10 wall switch...when someone walks
by, the wireless sends the turn-on signal to the wireless receiver.
The receiver puts the signal on the AC line and the switch receives it
and turns the light on."

I assume the switch fits in a standard box, right? The current switch
setup is 2 switches in one box: A STSP switch for the outside light
and a 3-way switch for a switched outlet. Best case is both switches
fit in the existing box - and still match. Is that doable - barring
any "this is an old house" - issues?

One more question: With most motion detector set-ups, you can override
the sensor by toggling the switch within 3 seconds to force the light
to be on all the time. Does it work the same way with the x10
switches? Can you turn the light on constantly with a toggle and then
reset it to motion-sense with another toggle?




Re: Motion Sensor Light for Front Entrance
On Sep 7, 11:11 am, trad...@optonline.net wrote:
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<Thanks. I'll look into it.

The fixture dad bought has all of the dusk-to-dawn, timer, etc.
features that you mentioned, which is what he wanted, so that's good.

re: "The next part you need is an X10 wall switch...when someone walks
by, the wireless sends the turn-on signal to the wireless receiver.
The receiver puts the signal on the AC line and the switch receives it
and turns the light on."

I assume the switch fits in a standard box, right? The current switch
setup is 2 switches in one box: A STSP switch for the outside light
and a 3-way switch for a switched outlet. Best case is both switches
fit in the existing box - and still match. Is that doable - barring
any "this is an old house" - issues?>

I think you're best served by not using X-10 - and this advice comes from
someone who owns every piece of X-10 gear ever made and uses it daily (along
with Jeff Volp's XTB booster - a must for any X-10 setup).  It's overkill
for this app and is likely to introduce more problems than it solves.  One
thing you might find is that there's no neutral at the switch - although the
presence of a nearby switched outlet means there's probably one nearby.
It's also important if you're going to use CFL bulbs.

CFL's don't play nice with X-10 (as well as a lot of other devices that draw
power from 110VAC line).  If you intend on using them, beware that many take
a long time to warm up and are basically unsuitable for walkway lighting.
Some CFl's even relight themselves when you turn them off under X-10
control - very annoying!  By the time the bulb comes up to max illumination,
you're long past the sensor and the light.

I'd pigtail the unit you have with some lamp cord to see if it works with
CFLs before going through the hassle of mounting it.  If the lights are
going to be on for a few hours, it would pay to use CFLs.  If the lights
will be strictly motion sensor operated, then normal floods would be the
choice of bulb.

<One more question: With most motion detector set-ups, you can override
the sensor by toggling the switch within 3 seconds to force the light
to be on all the time. Does it work the same way with the x10
switches? Can you turn the light on constantly with a toggle and then
reset it to motion-sense with another toggle?>

Ha.  Not that I know of, but there's always something new under the sun.
X-10 just requires too many pieces to do what a dedicated motion sensor
light does.  I have a full set of X-10 motion detector floodlights sitting
in a box in the attic because they were not as easy to use as dedicated
motion detector floods.  I use dedicated, self-contained units for the
driveway fitted with tungsten floods, but I also have CFL fixtures that are
X-10 controlled that I had to run new wire to get them to function
correctly.  None of my circa 1940 house's built-in fixtures have neutral
wires and CFLs just flash away like strobe lights in such circuits with X-10
switches.  X-10 trickles a tiny bit of current through tungsten filament
bulbs to operate.  CFL don't pass that trickle current - they just absorb it
until enough builds up to flash the lamp.  Very annoying.  Sometimes, the
flashing is enough to activate the X-10 "current sense" switching and the
light comes back on several seconds after you turn it off.

It could be that your units will be mounted so that they really will detect
motion where you want it detected, but units that allow you to swivel the
detector head are much better.  Read the instructions carefully regarding
neutral connections.  I think you're going to be good to go because the
switched out *should* require a neutral in the same gang box, but only your
tester knows for sure.  Beware that lots of tyro electricians mistakenly use
a ground wire when they should be using a neutral - your box may be that
way - it's a sin I've seen too many times to count.

--
Bobby G.



Re: Motion Sensor Light for Front Entrance
[snip]

 CFL don't pass that trickle
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X10 RECEPTICLE modules don't have the current sense "feature" but for
some strange reason still have the trickle current. A CFL won't be
completely off unless you have some other load connected too.

[snip]

--
108 days until The winter celebration (Saturday December 25, 2010
12:00:00 AM).

Mark Lloyd
http://notstupid.us

I believe in life before breakfast.

Re: Motion Sensor Light for Front Entrance
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But not another CFL load!  I just tried running two CFLs from a splitter
plugged into an appliance module and "bang-bang" both turn themselves back
on, in serial order.  The load has to be something that absorbs the trickle
current completely, and that's usually a tungsten lamp, although it can be a
non-PS power supply or other type of device.

While there are many "mods" listed for turning off local current sense, I've
found that they don't eliminate the flow of trickle current into a CFL and
thus, they still flash but at least they won't spontaneously relight.  It's
such a bummer that X-10 should really come out with a CFL-friendly control
module.  I am surprised they haven't, given the potential scope of the
problem with the phase out of tungsten bulbs.  Hmmm.  Years of Usenet have
taught me to Google before bashing.

OK - just checked with X-10's live support.  They are still pushing AM466
modules which flash and relight like crazy!  The actually called me on the
phone (sales, not techie) sent me three useless links, said it was "noise on
the line" (tell that to three different X-10 meters I own that say "no
noise") and were pleasant, friendly and yet totally unhelpful in solving the
flashing problem.  Google seemed to intimate there was a new, CFL-friendly
module, but it had actually done the annoying trick of turning my search
words into a mis-labeling of a link to the plain old
flash-like-a-turn-signal AM466 appliance mod.

--
Bobby G.





Re: Motion Sensor Light for Front Entrance


[snip]
 
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Right. The setup in my bedroom is a lamp with 100W CFL and a TV (I got a
small Visio LCD TV that is not "power amnesiac" (comes on with power))
connected to a receptacle module (SR227) which does not have "local
control" and the TV provides enough load.

[snip[

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I seldom find "customer service" to be helpful, but at least you got
someone you could talk to. I just had a really bad experience with a
wireless (CDMA) broadband carrier, where the person ignored 90% of what I
said.

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--
108 days until The winter celebration (Saturday December 25, 2010
12:00:00 AM).

Mark Lloyd
http://notstupid.us

I believe in life before breakfast.

Re: Motion Sensor Light for Front Entrance


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The Green Police are making those non-amnesiac devices harder to find.  My
RCA TV is one, and when you turn it back on with the IR after shutting it
down via X-10 it covers the lower half of the screen with a whiny warning
about the clock losing its settings.  Hey, you're a TV, not a clock!!!!
STFU. (-:

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"Flashing" is also dependent on the type of lamp.  I have some GE's that
don't flash but that are X-10 signal suckers and some N:Vision (HD brand)
bulbs that flash like demented fireflies.  X-10 needs to make a CFL friendly
control module.

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I've found if you're even moderately knowledgeable about a product it takes
two escalations to get someone who's not reading from an IF THEN ELSE chart
and who can actually troubleshoot.  X-10's tech support came in as "Unknown
name/Unknown number" on caller ID, FWIW.  Once I heard her speaking I knew I
was not going to get a good answer.  I hope I don't regret giving them my
phone number.

--
Bobby G.



Re: Motion Sensor Light for Front Entrance


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And I have two settups using X10 with CFL and both work perfectly.
One uses the plug-in appliance module with a 100W CFL in a desktop
light.   The other is the X10 wall switch that powers 4 small candle
type CFLs, maybe 25W each at the front door.  Both go totally out when
off.

I guess it could depend on the design of the CFLs.

Re: Motion Sensor Light for Front Entrance


On 9/9/2010 12:43 AM, Robert Green wrote:
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Two possibilities here:
I have a whole load of the Universal
Modules, which I used in a previous
life, for Halloween animation.  I
modified the UM to remove the screw
terminals and I then added a 1 foot
pigtail with a female receptacle.
Actually, it was cut off from an
extension cord, so there were 3 outlets.
  The wire went into the place where the
screws were, formerly.  I've read that
the contacts are rated for line voltage,
but because of the exposed screw
terminals, the unit was only rated for
low voltage.  Anyway, as this is just a
plain make contact in series with the
load, it works good on the CFLs that
where blinking with the module off.  I
am now presently using this on in my
living room.  One sort-of problem, these
modules click REAL LOUD.

The 2nd possibility is regular
lamp/appliance module modification.  I
have seen modifications that make a lamp
module into a click-free appliance
module.  One uses a solid state relay.
The other uses some other parts.  These
modification eliminate the sense current
completely.  Google click free or quiet
module modifications.


Re: Motion Sensor Light for Front Entrance


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a
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knew I
my

I have a bunch of UM's, and they do indeed clack, but I am too much of a
pussy to pass 110VAC through a contact spec'ed for 33VAC.  You're proving
that it can be done.  I'm saying "Hey, X-10, why are you forcing people like
Art to do your design engineering for you?"

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The SSR mode looked interesting, but I am reluctant to do much more than
snip a wire or cut a surface trace.  X-10's final solution was to use a 7W
nightlight to counteract the flashback of a bulb I am using to saving
electricity.  Add in the 4 watts for the X-10 module and another 4 watts for
the controller and the economics start to sour.  A fully equipped X-10 house
draws considerable standby current.  I remember measuring mine at close to
400 watts.  In a lot of places, the flashing hardly matters and it's
actually the most efficient low leveling night lighting you can get (if
you're not epileptic).  I''ve tried a lot of the mods, and while they do
eliminate the local control, they don't stop the current trickle!!!!!

The twin bulb 40W fixture in the workshop finally failed so I replaced it
with a new, high eff. unit.  Now it flashes with the same intensity as
nearby lightning does.  Surprisingly, you can navigate quite easily if you
move slowly.  More than enough light to see a black cat sleeping on a dark
rug.  Seeing a white dog is no problem.  Low SAF and neighbor approval
factor, though.  Went back to a manual switch (shudder) for the time being.

--
Bobby G.




Re: Motion Sensor Light for Front Entrance


On 9/9/2010 7:30 PM, Robert Green wrote:
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As for the UM, yes the click is horrible
... worse than the generic appliance
module.   I'm not sure where I found it,
but, someone reported that the relay
contacts were actually rated at line
voltage.  The exposed screw terminal are
what actually made them put a spec of
33VAC on the module.  As you said, I'm
proof that it works but I don't have any
hard documentation showing the contact
rating.

Also, when you said your house had an
X10 standby load of 400 watts, I can't
see how.  I am assuming you mean from
modules and such.  Today I connected 8
generic lamp modules to a Kill-A-Watt
unit.  The 8th module made the display
go from 1 watt to 2 watts.


Re: Motion Sensor Light for Front Entrance
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Yes and no. It doesn't indicate fractional watts so you need to use the kWh
mode and measure over a long time frame. I measured several X10 modules this
way for ~100 hour periods. See...

     http://davehouston.org/x10-power.htm

NOTE: The readings were under no load conditions but I doubt that the
trickle current will be that significant.

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In-line amperage measurements are worse than useless with non-linear loads
like these. The Kill-A-Watt takes thousands of instantaneous readings of
both voltage and curreny each second and then averages them to get a very
accurate reading. The kWh mode has 30ppm accuracy.

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I've neen dealing with major health issues (and have additional surgery
scheduled). As for my measurements, I did exactly the opposite, refuting
numerous people who were claiming X10 modules used 5-10W based on ammeter
readings.

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Don't waste your time - this method is, as noted above, worse than useless -
worse because it is extremely misleading.

Re: Motion Sensor Light for Front Entrance
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they've
kWh
this

Yes, senility strikes again.  But I demand half credit - I remembered that
it happened and that you were involved and believe me, like the Langoliers,
things out beyond a certain distance are getting all dark and hazy and a
little bit scary.

I did recall the most important result of your research to me, at least
concerning the Kill-a-Watt.  For low end reading to be accurate, low power
loads needed to be measured over time and there was a reason that you
couldn't just take the Kill-a-Watt's low current, instant readings as
gospel.  Thanks for correcting my "holey" memory.  One hole filled means
something else just leaked out, though.

The amount of trickle current - do you think it varies in some way with the
nature of the load connected to it?  Does the current that causes CFL's to
flash also heat a tungsten filament slightly or does the differing nature of
the load affect how much current is passing?

I get some pretty serious flashing of two hi-eff 34W fluorescent tubes in
the workshop - enough to see by if you move very slowly (-;  It would be
easy enough to first to compare an appliance module's power consumption
without such a load and then with.  In about 200 hours or about 8 days from
now.  (-:

So, 100 hours reading an appliance module, no load v. 100 hours reading
appliance module with the two bulb shoplite that flashes more brightly than
any other fluorescent in the house.  I can even supplement those with
readings of an appliance module with a small CFL and another with a 100W
tungsten bulb.  I also want to see what it costs to run a 7W nitelight with
a CFL load since it's now X-10's tech support recommendation to cure the
flashing problem.  No wires monsters, no lights in boxes - it should get
safety approval.

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power

The issue I ran into was the limit imposed on the plug in outlet on Jeff's
XTB.  It's got a wattage limit for plug in devices, I believe it's either 10
or 15W, but I could be wrong. I measured the devices with a Kill-a-Watt (2
Maxi's, 1 ControlLinc Maxi, 1 Mini controller and a Mini Timer that uses a
wall wart transformer and not the standard X-10 type power supply).  The
Kill-a-Watt gave me a very low number that was below the limit imposed by
the XTB, and so I plugged them all into one unit and it worked. I did not
measure it using the accumulation kWh mode because waiting around for 100
hours to get a reading is not very practical, but alas, seems necessary when
dealing with low wattage items using the Kill-a-Watt.  FWIW, the
ControlincMaxi's nameplate lists 100mA, the X-10 lamp and appliances modules
list no wattage information, and the X-10 Mini lists 2 watts.

The XTB operated quite well with 5 units plugged into the amplification
outlet UNTIL I removed the Mini-timer with the wall wart.  Then, it fried.
When it happened, I got into a discussion with Jeff Volp who immediately
went over my admittedly low altitude head with discussions of mixed reactive
and inductive loads on both his circuit and the metering methods I was using
to make sure I was within the wattage range specified on the XTB label.  It
was, as they say in the Army, above my pay grade.

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Welcome back!  Been a while since we last heard form you.  Sorry that you're
still having health issues.  I hope all goes well with your medical
procedure.

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<Sigh>  It seems I lost the decimal place in the fog of senility.  Your
figures were .4 and .5 and not 4 and 5.   I hopefully still have my notes
around, but I distinctly recall a metric you used was that they were much
cooler to the touch than a 7W nightlight, giving a "rough" reading that said
common sense dictated it had to be below 7W.  That's when I decided that
under careful enough controls, the relative amount of heat output between a
module and a 7W night lite could be used to verify readings with meters,
that for whatever reason, gave erroneous readings at the low end as when
used in a typical way.  (Like me!)

IIRC, and it's clear I don't "Recall Correctly" anymore, they did make the
heat in a closed, insulated box rise respectfully.  They were clearly
drawing power that could be measured as heat output.  I recall they differed
from your readings, but I also recall the experiment being shut down by the
resident safety engineer, Ms. Swmbo.  The idea of enclosing electronic gear
(especially lamps) in wooden boxes lined with Styrofoam did not pass muster,
even though it was "unlikely but not impossible" to start a fire.  I might e
ven have the readings saved in a draft message.

I believe the modules I was running were running under load because I wanted
to know the effect and size of the trickle current flow.  That was when
CFL's had just gone mainstream and  I first noticed the flashing problem.  I
began delving deeper into how to measure the trickle current flow, but
someone, I think it might have been Dan L. advised against it, charitably
citing safety concerns but more likely having to do with the primitive
equipment and skills I possess. (-:

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batch
useless -
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Certainly when using X-10 modules and their linear power supplies.  Am I
right to assume an in-line ammeter would be much more accurate with
inductive and purely resistive type loads?   I would assume by the short
time between the posts that Art took an instantaneous measure, and not an
averaged one.  But I'm Often Wrong, so only he say for sure.

At least all this is what I recall when I insisted to an incredulous Jeff
that the XTB had been running with no incident with all five X-10 items
listed above plugged in via power strip.  I am sure he'll be around to
correct me shortly as well.  As I said, this is really outside my bubble.
The XTB problem occurred AFTER I REMOVED the sole inductive load (a
wall-wart powered Mini-timer) from the powerstrip with the other four
components.  It seems quite counterintuitive that reducing the overall load
caused the XTB to burn up, but apparently the combination of inductive and
linear loads on the XTB was preventing the load from burning up the XTBs
input circuitry.  I won't paraphrase Jeff's explanation and embarrass myself
further.  Maybe he can reiterate for us.

I should note that Jeff both offered to repair the unit free and changed the
labels and instructions to accommodate the unusual results I discovered by
flagrantly disregarding the label warning.  Now, in addition to the wattage
limit, he indicates that no more than two X-10 devices be plugged into the
XTB's amplification outlet.  I think a lot of non-engineers and techies have
real problems understanding the intricacies of the different types of
devices as well as other concepts, like the PF (power factor), phase angles
and so on.  I know I do!

If reactive and inductive loads can interact as they apparently did with the
XTB, is it possible that measuring multiple modules and dividing that
outcome as both you and Art did is not actually equivalent to reading a
single unit?  I assume you did that because reading single units that draw
under a watt is problematical for the KaW, even in the kWh "accumulation"
mode.

Good to here from you again, Dave, even if you're still correcting the
living hell out of me and shaming my Mad Cow brain - that has to be it - Mad
Cow.  Anyway, that's how we learn, even if the ego gets a little burned
around the edges.

And again, here's to a good surgical outcome.

P.S. to Art.  Glad you asked this question, nothing at all's changed but I
feel alot better that X-10's not eating 400 watts just "being there."  I
feel a lot worse though, about where all those extra watts are going.  A
while back someone suggested that the older the house wiring, the more
likely substantial amount of juice are going up in heat in the wires.  That
would not be good. )-:

--
Bobby G.



Re: Motion Sensor Light for Front Entrance
Rather than further spaghetti-ize things by trying to respond inline to your
inline comments, I'll just p*ss off all the anti-top-posters and try to
respond to your major points here.

Inline ammeters only work for purely resistive loads where voltage and
current always remain in phase with each other. With reactive loads
(inductive or capacitive), voltage and current are 90 out of phase,
requiring multiple, simultaneous measurements. Power=Voltage*Current so
averaging each doesn't work. You have to average the products of the many
readings.

Non-linear loads are usually those related to power suplies with diodes that
tend to draw current only at certain points in the voltage sine wave. These
also require multiple, simultaneous measurements.

I'll leave it to Jeff Volt to explain why you had the problem with the XTB.

CFLs have non-linear power supplies which cause (small) surges, triggering
the X10 flashes.

You really don't need the closed box. Just put your hand on the 7W
nightlight. It should be hot enough to be quite uncomfortable. IIRC, I used
3W which was still uncomfortable. X10 modules (with no load) have to
dissipate the heat associated with the idle load they represent. They never
get too warm to touch (unless defective) so this is a quick and dirty sanity
check whenever someone suggests they waste significant power.


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Re: Motion Sensor Light for Front Entrance
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Most inexpensive X10 devices have transformerless power supplies, which use
a capacitor to drop the line voltage to the low level needed by their
electronic circuitry.  The charging current is reactive, which is not
in-phase with the applied voltage.  The Kill-a-Watt has two ways to measure
power consumption - watts and VA.

Watts is the "real" power that you pay the electric company for.  VA (volt
amperes) is the average of the real-time multiplication of voltage and
current over the entire AC cycle.  Purely reactive loads will draw current
charging up at one point in the AC cycle, and dump that energy back to the
poweline elsewhere in the cycle, resulting in no "net" power consumption.
However significant current can be drawn during the charge and discharge.

The amount that VA differs from watts is a function of the power factor of
the device.  When the power factor is 1.0, the VA and watts will be
essentially the same.  At lower power factors, the numbers can differ by
large amount.  For a Maxi Controller, the Kill-a-Watt reads 1.0 and 10 for
watts and VA respectively.  Even though the Maxi Controller label says it
only consumes 2.5W, the low pass filter in the XTB must deliver the same
current as if a 10W load was plugged in.

You can think about this in another way.  If you stick a big capacitor - say
2.2uF - into an AC socket, it will pull about the same current as a 1200 ohm
resistor.  If that were "real" power (watts), the capacitor would dissipate
about 12 watts.  However, the capacitor won't even warm up because the
current is "imaginary" (90 degrees out of phase with the applied voltage).
I just verified this with my own Kill-a-Watt.  It measured 0 for watts, and
11 for VA with a 2.2uF capacitor.

The power supply in a X10 transmitter functions a lot like that capacitor.
The only "real power" that the Kill-a-Watt measures is that actually
consumed by the module electronics.

It the case cited earlier wherein the XTB low pass filter was overloading by
removing one of the 5 loads, that one load had a power transformer.  So, its
"imaginary" inductive current was opposite that of the other X10
transmitters, partially canceling out their effect.  When that load was
removed, the current pulled by the 4 remaining capacitive loads (about 40VA)
exceeded the rating on the XTB low-pass filter inductors.  This is similar
to the issue that the power company deals with by placing capacitors in
their distribution network to balance out the inductive reactance from the
various motor loads.

I realize that this may be a difficult concept for some.  Hopefully, the
capacitor example above will help you understand the issue.

Jeff



Re: Motion Sensor Light for Front Entrance
 
Quoted text here. Click to load it

Which is why the power companies charge industrial and other customers, with
large reactive loads, a premium. They have to supply (and have the
infrastructure for) the higher current even though it does no work.

It is also why CFLs may not bring about as big a reduction in power usage as
claimed by those who foisted them on us. Instead of merely banning
(effectively) incandescents, they should also have mandated that CFLs have a
high power factor or, at least, require the manufacturers to put the PF on
the package.

Re: Motion Sensor Light for Front Entrance
Quoted text here. Click to load it
many
use
measure
say
ohm
dissipate
and
by
its
40VA)
Quoted text here. Click to load it

Thanks for the detailed explanation.  It's actually quite suprising how much
I've learned about the X-10 transmission process just following this group.

--
Bobby G.




Re: Motion Sensor Light for Front Entrance
I'll see your top-posting and raise you one.  It's amazing how the net was
really like Camelot.  For a little while it really did represent an amalgam
of viewpoints and information from across the world, a real roundtable of
ideas.  Then came the commercial corruption. And netcopping and lots of
other "badness."  IMHO, top posting is a very logical and "page down palsy"
free way of reading a thread.  Obviously not everyone agrees.  I guess
that's human nature.

Between the explanations both you and Jeff have offered, I understand better
what some of the issues are and why it's difficult to read the power
consumption of X-10 modules with garden variety meters.

I agree the hand method is clearly the best sanity check.  IIRC, I was
trying to determine the amount of heat generated by a lamp module in the
dimmed state, where they do tend to heat up quite a bit more than an
appliance module because of heat generated by the triac. When I went to look
up the phrase "Why do triacs get so hot" one of the first 10 Google hits
confirms my contention that the old WWW ain't what she used to be:

How Can I Become Hot? - GirlsAskGuys.com
I wanna be hot because then I will feel good about myself and get more
attention. The question is: what should I do? I was kind of a tomboy growing
up so I ...
www.girlsaskguys.com > Style Questions - Cached - Similar

<sigh>  How does something like that come back in a search that includes the
word triac?

I assume there's some resistance in the triac and some of the current
passing through it is dissipated as heat, and the more current the more
heat.   I am only curious because the lamp module I melted by running 1000W
through it still works.  It just looks like it's part of that Dali painting
with the distorted clock faces.  I assume the issue is that while the
circuit can handle the wattage, the case design can't dump the heat fast
enough to keep it from melting.

--
Bobby G.



Quoted text here. Click to load it
your
that
These
XTB.
used
never
sanity
devices
measure.
that
Langoliers,
power
the
to
of
from
than
with
the
loads
of
very
Jeff's
10
(2
Quoted text here. Click to load it
a
when
modules
fried.
reactive
using
It
you're
ammeter
said
a
the
differed
the
gear
muster,
might e
wanted
I
suitable,
load
and
myself
the
by
wattage
the
have
angles
the
draw
Mad
I
That



Re: Motion Sensor Light for Front Entrance
Not to further the off-topic but...

I totally agree with the reference material as an attachment (below)

The advancement to threading newsreaders has obsoleted the need to bottom
post and / or even attach reference materials, at all, except when the
previous post being responded to contains multiple ideas that could confuse
the isolated response idea.

Threaded response posting is even worse and can only survive a few
generations. It usually indicates "too much to say".

Top posting keeps the ID headers with the text they belong to. Note the
bottom posting confusion here at the bottom. Multiple colours and other
special reader techniques have been implemented in order to keep the bottom
posting confusion from happening over the years. Why bother?


I'll see your top-posting and raise you one.  It's amazing how the net was
really like Camelot.  For a little while it really did represent an amalgam
of viewpoints and information from across the world, a real roundtable of
ideas.  Then came the commercial corruption. And netcopping and lots of
other "badness."  IMHO, top posting is a very logical and "page down palsy"
free way of reading a thread.  Obviously not everyone agrees.  I guess
that's human nature.

Between the explanations both you and Jeff have offered, I understand better
what some of the issues are and why it's difficult to read the power
consumption of X-10 modules with garden variety meters.

I agree the hand method is clearly the best sanity check.  IIRC, I was
trying to determine the amount of heat generated by a lamp module in the
dimmed state, where they do tend to heat up quite a bit more than an
appliance module because of heat generated by the triac. When I went to look
up the phrase "Why do triacs get so hot" one of the first 10 Google hits
confirms my contention that the old WWW ain't what she used to be:

How Can I Become Hot? - GirlsAskGuys.com
I wanna be hot because then I will feel good about myself and get more
attention. The question is: what should I do? I was kind of a tomboy growing
up so I ...
www.girlsaskguys.com > Style Questions - Cached - Similar

<sigh>  How does something like that come back in a search that includes the
word triac?

I assume there's some resistance in the triac and some of the current
passing through it is dissipated as heat, and the more current the more
heat.   I am only curious because the lamp module I melted by running 1000W
through it still works.  It just looks like it's part of that Dali painting
with the distorted clock faces.  I assume the issue is that while the
circuit can handle the wattage, the case design can't dump the heat fast
enough to keep it from melting.

--
Bobby G.



Rather than further spaghetti-ize things by trying to respond inline to
your
inline comments, I'll just p*ss off all the anti-top-posters and try to
respond to your major points here.

Inline ammeters only work for purely resistive loads where voltage and
current always remain in phase with each other. With reactive loads
(inductive or capacitive), voltage and current are 90 out of phase,
requiring multiple, simultaneous measurements. Power=Voltage*Current so
averaging each doesn't work. You have to average the products of the many
readings.
Non-linear loads are usually those related to power suplies with diodes
that
tend to draw current only at certain points in the voltage sine wave.
These also require multiple, simultaneous measurements.
I'll leave it to Jeff Volt to explain why you had the problem with the
XTB.
CFLs have non-linear power supplies which cause (small) surges, triggering
the X10 flashes.

You really don't need the closed box. Just put your hand on the 7W
nightlight. It should be hot enough to be quite uncomfortable. IIRC, I
used
3W which was still uncomfortable. X10 modules (with no load) have to
dissipate the heat associated with the idle load they represent. They
never
get too warm to touch (unless defective) so this is a quick and dirty
sanity
check whenever someone suggests they waste significant power.



Quoted text here. Click to load it
devices
measure.
that
Langoliers,
power
the
to
of
from
than
with
the
loads
of
very
Jeff's
10
(2
Quoted text here. Click to load it
a
when
modules
fried.
reactive
using
It
you're
ammeter
said
a
the
differed
the
gear
muster,
might e
wanted
I
suitable,
load
and
myself
the
by
wattage
the
have
angles
the
draw
Mad
I
That




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