HELP with automating LED lights


Old 03-26-11, 08:30 PM
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HELP with automating LED lights

Ok I replaced our Front outdoor foyer light fixture (2 13watt CFL) with a bathroom vanity style fixture with 3 1 watt LED's

the 3 1 watt bare bulbs are actually producing more light than the 2 13watt CFL behind the translucent glass housing. IE the foyer is now brighter :-) nice :-)

but I want to go EVEY FURTHER than saving 23 watts of power here. I want to save 25 watts.

I want to use ONE 1 watt LED bulb and then have a motion sensor kick on the other 2 bulbs when anyone is in or near the foyer. so when I turn on the light 1 bulb turns on and if anyone is in or near the foyer the other 2 bulbs would turn on for X time and then off going back to ONE bulb.

rigging this up so it randomly selects which 1 bulb is on and which 2 are the "on off" for motion sensing would be even better (even out the wear and tear on the bulbs)

would be even cooler if it shifted which ONE bulb was on when the motion sensor is not tripped so think every 20 minutes it would change which single bulb was "on"

would also love to hook this to a light sensor so the light comes on at dusk and "goes off" at 0200 but turns back on if it sees motion. IE this would make it 100% transparent it would "just work" automatically.

Suggestions on how to do EITHER of these methods?

#1 dumb on off but 2 only when motion triggered.

#2 the intelligent shifting timer getup

any help would be greatly appreciated! oh and it needs to consume less than 1 watt otherwise it would be cheaper to just leave them on :-) hehe

I am going to try and find a cheap motion sensor that will work with such low power (2 watts)

any suggestions would be wonderful and appreciated !!
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Old 03-27-11, 06:03 AM
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Are they screw-in LED bulbs or did they come as part of the fixture?

If bulbs, two screw in motion-sensing light sockets will accomplish the first. Each motion sensor will draw about 1 watt in off mode.

I know of no off-the-shelf devices that will do the intelligent shifting. Worse, if you use the screw-in sensors it will prevent those lamps from turning on as part of a switching circuit. To accomplish both you would need to add some fairly advanced circuitry. The power supply for that circuitry would definitely wind up using more power than the lamps themselves.
Old 03-27-11, 10:11 AM
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yeah no point at 1watt the bulb only consumes .9watts each :-)
Old 03-27-11, 01:30 PM
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Hi, Nerys, long time, no read.

What you propose could be done but as Rick points out it would be a one-of-a-kind engineered system, fairly complex and somewhat costly to implement. The motion sensor would indeed be using "vampire power" at all times so the savings would most likely be negative.

You could use a pair of time clocks to have the entire system come on at dusk and off at dawn (or some other time frame) while the second time clock would have the second and third LED come on during more normal visiting hours. Or you could use a manual switch to turn on the second and third LED when answering the door. The trouble with this is that you need an astronomic time clock that will automatically adjust to sunset/sunrise or else adjust it manually every few days. Another problem is that the time clock will also take some "vampire power" to operate which might be more than the LEDs.

Yet another idea would be a three-wire photocell to turn on the light and then a time clock to turn it off before dawn. Trouble with ALL these ideas is that they will likely take more power than just leaving all three LEDs on 24/7/52.

So, how much have you been able to reduce the electric consumption and have you calculated the capital cost to produce the savings and payback time? I finally got my LED night light installed in my kitchen ceiling but so far I just turn it on and off manually and have it connected to a sealed lead-acid battery than I recharge about every two weeks. Between health problems and working on my sister's home (she doesn't want anything but plain old incandescent lights ) I haven't made any more progress in my LED experiments.
Old 03-27-11, 02:22 PM
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The savings are pretty dramatic. of course hard to "see" since there is no "line item" on the electric bill that says Front Door Light :-) but some quicky math.

I pay 14.8c/kw delivered in the summer 11.6c/kw in the winter or an average of 13.2c/kw (I am assuming 6 months winter 6 months summer rate I don't actually know when it changes or if its gradual or sudden I will figure that out later)

so switching from 26watt CFL to 2.7watt LED's.

CFL cost $2 LED cost $18 difference $16. this is what I need to save in E to make it worth while.

if we assume 10 hours per day running thats 3650 hours or for the CFL's $12.53 per year and the LED's $1.30 per year.

SO I save $11.23 per year JUST from the front porch light so 17 months to break even.

the LED should last at LEAST 10 years if they are designed properly 20 years if they are designed REALLY well.

if we assume 10 years they will pay 7 times over PLUS I won't have to goto the store and buy 3 more "sets" of CFL's in that time span so add in gas time and cost of more CFL's and they pay for themselves almost 10 times over in their minimum lifespan.

SO good fast ROI and significant savings that are measurable. ie will save me well over $100 in their lifespan.


I have a little over 50% of the house all LED now. Kitchen is LED (went from 85 watts to 18watts at a cost of $60)

Bathrooms (3) are 100% led. Laundry room is LED. 2 bedrooms are LED and both hallways are LED and now the front porch is LED.

As money permits I will convert more of the rooms to LED until there is nothing but LED bulbs in the entire house except one room. The garage. We use that light SO little that there is simply no logical reason to goto LED at my currentl budget limitations. 23watt CFL's just make more sense in their.

otherwise I will 100% convert to LED. I do NOT LIKE any led less than 70 lumens per watt. This means I avoid those expensive worthless phillips bulbs etc.. like the plague. They are like hybrids. made to make you FEEL good without actually doing anything good or saving you any money. :-)

Also working on making the CAR all LED as well. including the headlights if I can manage it. save gas :-)

the hard part is finding good LED with nice warm light where they are NOT over driven IE getting "HOT" (anything over 100'F is "bad bad bad" for LED's ie slightly more than your skin temperature.

Most run WAY to hot and don't last a year if not a few months.
Old 03-27-11, 03:10 PM
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Sounds good! Of course the lack of any individual usage hours or actual "before and after" kWh readings makes it a bit harder to make verifiable observations.

My electrical rate is significantly less than your, 8.362 cents per kWh winter rate with the summer rate a few hundredth of a cent less. No transport charges and the only additional cost is a 6% municipal tax that I should be able to get a rebate on after next year due to age and income. I live alone and my consumption is pretty close to an average of 9-10 kWh per day year round unless we get unusually hot weather for the area and I need to run A/C. This gives me a fairly constant billing of about $28 a month (billed every other month) so not a whole lot of incentive for major conservation projects.

I have three, 13 watt CFLs on the front of my house that run dusk-to-dawn on a photocell. If you remember I tried some LEDs I got at Sam's Club that stated they were equivalent to 40 watt incandescents and while I could certainly see the lamps from the street (maybe fifty feet away) they offered almost NO illumination to the area so I took them back. I figured roughly that using the CFLs instead of 60 watt incandescents saved me about $2.50 a month averaged over the course of a year plus the CFLs would last anywhere from one to four years vs. about three months for the incandescents. The last CFLs I bought were about $5 for a pack of six so that makes them considerably less expensive than incandescents.

I am always checking the Lumen output of "comparable" CFLs vs. LED and incandescents and it just fries my 'nads how they can state that an LED of 400 Lumens is"equivalent to" a CFL putting out 600 Lumens or an incandescent putting out 750 Lumens. I'd like to replace my bedroom lights (65 watt incandescent R-30 recessed) with LEDs but the cost is outrageous and I don't think I would like the greatly reduced light output. The recessed CFLs are okay for light output ONCE they come up to full brightness but the bulb (only one right now since my sister has all my ladders) takes five fricken' minutes for that. The two CFLs I have in the bathroom take less than thirty seconds to come full bright.

The rest of the house just doesn't make much sense in changing the lighting except maybe the kitchen. Everywhere has recessed R-30 incandescents but with the exception of the kitchen the lights are rarely on for more than a few hours a month and it would take forever to payback any retrofit. I often think about a Solatube skylight for my kitchen so I didn't have to turn on the lights during the day but at my electrical rates it would take about ten years to see any payback on electrical consumption.
Old 03-27-11, 06:41 PM
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before and after are not relevant. 2 13watt CFL's consume 26 watts. 3 .9 watt LED's consume 2.7 watts.

there is nothing to verify or get before and after for here. They are verified by their very existence.

HAH our average bill is around $200-300 a month !! before I started going LED and CFL we were pushing $300-$400 OR MORE a month.

we have a large household with 8 people living under one roof. so yeah our power usage is orders of magnitude higher.

the trick with LED is low wattage arrays. ie for my front porch I use 3 .9 watt LED's they are claimed to put out 270 lumens.

the 2 CFL's claim what?? 800 lumens? so 1600 lumens but by the time the light escapes from he translucent enclosure etc.. you end up with less light than the 2.7watts in LED put out.

replacing CFL or INCANCES with LED 1:1 is near impossible and IS impossible financially (IE to save anything)

Home Depot has some nice 8 watt LED bulbs that put out around 40-50 watt equiv lumens (and it really does too)

its expensive at $17 a pop but the light is very good and very clean.

remember LED is highly directional so you need DIFFERENCE fixtures. they don't work well on bottom socket fixtures. you need fixtures where the socket is in the TOP so the bulb faces DOWN and where there is almost ALL GLASS at the bottom so not structure to "block" the light.

works much better that way.

if your doing $28 a month you don't really need to do much. ROI for you is going to be incredibly long because of your crazy low usage (though I guess its actually that my usage is crazy high)

Check out the bulbs if you can find them a walmart. $6 a pop they are fiet electric "accent" lights. .9 or 1.1 watts each 70 lumens and very tiny.

I will post pictures later. You might also want to check out the 2 watt LED bulbs at SAM's Club. $20 for a two pack so they are $10 a pop.

you won't save money too fast in electricity but you will save money in gas by not having to go get and replace bulbs so often (they appear to be working very well so far)

I use 2 in my hallway and they work very well. not super bright but more than bright enough. I would prefer 3 but can live with 2 (I will goto 3 if I can find a nice 3 bulb ceiling lamp fixture) or 4 of the 1 watters. (they put our more lumens per watt than the 2 watters at least visually)

Stay away from the lights of america LED's I have had nothing but bad luck with them.

CFL is a no brainer switch any incans you have left to CFL. you can get VERY nice very good soft white good color fast warm up CFL's at Dollar Tree for $1 a pop. they are rated for 12,000 hours and so far they seem to be holding true to that.

Your savings won't be huge but just ONE GAS trip to go get more Incans will cost more than the CFL costs its so cheap now.

we have a lot of lights 3 stories and everyone LOVES leaving the stinking lights on. Grrrrr :-)
Old 03-27-11, 08:31 PM
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We're probably going to be shut down for going "off topic" but this is interesting.

I'm an engineer, or was before I retired. Verifiable field evidence was absolutely necessary for me to convince accounting personnel and often even fellow engineers. You might be surprised at the number of otherwise intelligent people that simply refuse to believe anything on a product package such as energy consumption vs. light output. I also had the problem that my (now former) company wanted a 12 month payback on any capital project. They would sometimes go for an 18 month payback but the savings after would have to be really large.

Turning off lights is a HUGE problem. My company spent tens of thousands, maybe hundreds of thousands, of dollars installing occupancy sensors and also breaking large areas into "lighting blocks" and having them computer controlled. Even then it was disgusting to me how some people would go into a mechanical space and immediately turn on every light in the space just to use the restroom and then leave with all the lights (MH) still not even up to full brightness. Closer to home, my sister (who is in love with incandescents and hates CFLs) is very bad about turning lights off. Since I suspect I will be paying her electric bills for some time I just have to do something.

Yes, LEDs are highly directional and that was as much the problem with my outside lights as their (relatively) low lumen output. My fixtures ARE the type with the socket in the upper half and they are open on the bottom with glass sides but with the LED lamp having the individual diodes perpendicular to the base it threw no light out the bottom and a goodly portion towards the wall. Unlike CFLs and incandescents, light from an LED just doesn't seem to reflect from anything but a mirror.

The biggest reason why I don't change most of my lighting to CFL is that the majority of my lighting is on dimmers and unless I buy "dimmer rated" CFLs (at a lot more money) they don't "play well" with the dimmers. I did change out the dimmers in my hallway (three lights) for switches and that alone was nearly $20 and I still have the same 65 watt R-30s. Since I don't use the hallway lights much (don't need it except when vacuuming) Slow-to-bright CFLs would just not work. Plus the forty-two cents a year it costs for electricity would make the payback something like 10,000 years! (Okay, that's an exaggeration but you see my point in not changing.)

Nor does it cost that much in automobile fuel since my R-30s seem to last forever. I think I have replaced five in the last ten years. I suspect it is the slow-start due to the dimmers.

Oh, I agree with you about anything that has "Lights of America" on it; their stuff is garbage in my opinion.

What do you have that is using so much electricity? Is it that there is at least someone up 24 hours a day? Electric kitchen and or water heating? Electric heat during the winter? Air conditioning? As I recall you live in southern California.
Old 03-27-11, 09:05 PM
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Yes everything in the house is electric. We switch from Electric to "gas" heat (still have electric heat too as backup) no cost savings. We save in E but pay for Gas and its about the same. although the gas heat is "faster" and "dryer" which everyone seems to like so whatever :-)

but yeah electric stoves oven hot water dryer washer etc.. all electric.

our largest expensive is probably hot water and dryer. 8 people take a lot of showers use a lot of hot water and wash a lot of clothing :-)

Lumen output means nothing to me (as long as its GOOD per watt otherwise it won't beat CFL) I just keep adding LED's till everyone agree's "ok thats bright enough" Then I do a watt for watt comparison.

in the bathroom I had to remove 2 LED bulbs from each fixture because everyone said it was too bright. oddly enough those are the 1.5 watt Lights of American bulbs that I can not get any longer Grrr. but bathroom lights have such a short duty cycle that they have not died on me.

the problem is we use WAY more light than we really need. for example in the bathroom I replcae 4 13watt CFL's behind translucent glass (52 watts of power consumption) and replace it with 5 1.5 watt LED's for a total of 7.5 watts and its BRIGHTER than the 52 watts of CFL's

is 7.5 watts of LED brighter than 52 watts of CFL? NOT A CHANCE.

but the LED's are BARE facing straight out and ALL the led face straight out SO you are utilizing almost 100% of the light almost 100% efficiently.

While the CFL's you were lucky (fixture design etc..) if you got 40% of the created light to actually do work.

BARE CFL's are ugly. because of the LED bulbs I chose bare LED's are beautiful.

in the kitchen (was running 12 1.5 watt LED bulbs) they died inside a year slowly but surely. the 2 watt GE bulbs are doing VERY well so far and I only need 6. I still plan to add 6 more and then use a variac to cut the lumens in half (so 12 are as bright as 6) this way I UNDER-UTILIZE all the components and get rid of any heat that might be generated IE double or triple the lifespan of the bulbs.

The kitchen was the same problem. I replaced a 85watt 4ft FL fixture. probably 60-70% of the light it produced did NO WORK AT ALL. it was a fancy BOX with a "window" like pane translucent milky white covering. most of the light was wasted BLASTING the inside of the fixture.

so when I hooked up 12 watts of LED's almost 100% of the light went in the RIGHT direction and did WORK.

now both have issues (I am fixing) in the kitchen you have less EXCESS light so under the cabinets is a little dark. MORE than enough to see by without issue but not as "pretty" so I am going to rig up 2 warm white 2.4 watt Christmas light strings under the cabinets to "fill" that shadow void. I got 25 boxes of them for 75 cents a pop on clearance :-) hehehe

in the bathroom at night the SHOWER STALL can be a little "dim" when you close the curtain. SO I am going to install a single 1watt down facing LED in the ceiling in the stall. to "fill" the shadow void.

for me anything less than 40k or 50k hours is a FAILURE in LED lighting.

its just a BIG house lot of computers lot of lights lot of people.

I am trying to AUTOMATE as much as I can to make it more user transparent. the wall I am running into is that I am getting the power for lighting SO LOW that sometimes (as in this example) the automation takes as much if not more power than just leaving the light on. !!! :-)

My ultimate objective is to REMOVE lights from the grid all together. while there is NO practical means for me to remove the house from the grid IF I can go all LED I can bring the wattage for the entire house down to around 350-400 watts (with every single light on except the CFL's in the garage)

so my "real time" watt usage would be around 50-100 watts max at any one point in time.

suddenly at this level running solar and battery becomes feasible. 40% of the countries power goes to lighting. if we could not only reduce power to lighting but REMOVE IT FROM THE GRID all together. well WOW. 40% reduction in power consumption nationwide is something to be impressed about :-) if everyone did it that is.

SO automation becomes important. if people have to WORK at it they just won't do it. people like me might people like you might but not your average joe. No way :-)

OUTDOORS is very very tricky. in a fixed space like a porch its easy. in an OPEN space its a lot harder to use effectively. the LED lumen limit rears its head and the light is just EATEN UP by the darkness.

for now your probably better off dollars wise going with CFL's

I am going 100% LED to make a point. to be an example. so I don't mind spending a little more to "do it" for the sake of doing it.

you should see my place christmas time. about 4500 LED's :-) hehehe

One other trick is to not just use less light but lower HOW MUCH LIGHT you actually need to use.

remove ABSORPTION mediums. WHITE appliance reflect more light. always use GLOSSY paints they reflect more light and are easier to clean too.

the BRIGHTEST WHITE glossy paint you can buy for the CEILINGS. any light absorbed by your ceiling is 100% wasted doing NOTHING the more you can reflect back INTO the room the less actual lumens you NEED to do the same work.

ie "light" the room more efficiently so you actually need LESS LIGHT to begin with.

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