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Barry T Coles

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Joined: 30/07/2009
Location: Australia
Posts: 109

Posted: 03:11am 04 Sep 2009

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I will be building a home in the near future & will be going for solar connected to the grid & complemented by F&P wind power am seriously looking at all lighting being 12 volt LED.

The reason for 12 V lighting is three fold, the area I am in is subject to power outages during summer due mainly to bush fires in National parks bringing down the lines or the Power Authority shutting the system down during these fires & low powered LEDS are less power hungry than conventional lighting & when grid power is lost the inverter systems have to shut off feed to the grid.

I have managed to find this Co in South Oz & tried out this light below & I am pleasantly surprised with the output, it has 3 LEDS @1 watt/LED & outshines a 30 watt diachronic down light hands down, it fits into the standard down light fitting.

I�d like to hear from anyone who may have gone down this path before.

Cheers
Barry

http://www.digielite.com.au/LEDLampbulb2.htm?gclid=CJ7v24mY1 5sCFYctpAodCnbo_A

DLMR16-3X1W5 12V 3x 1W Power LED White (3500K, 6500K)

I need to learn from the mistakes of others.
I dont have the time to make them all myself.

rep334
Newbie

Joined: 04/09/2009
Location: Australia
Posts: 2

Posted: 09:12am 04 Sep 2009

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Hi Barry,
if 12 volt led `s are your fancy I have several options for you .
Have a look at the web address

http://www.hafele.com.au/isapi/online/reflections/reflection s.asp

There are several new options ,

This version is 240 volt but these are available in 12 volt DC.
There are 3.3 watts and 4.5 watts
I have samples and they are fantastic with the out put .

I run these in my house ( 240 volt ) but have 12 volt solar available .
To contact me fernbrae5@bigpond.com

rgds Greg

love life and still living

rep334
Newbie

Joined: 04/09/2009
Location: Australia
Posts: 2

Posted: 09:15am 04 Sep 2009

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I am sorry I forgot to tell you that the 4.5 watt is equal to a 11 watt cfl globe .( 60 watt incandescent )
these are a real eye opener and of course look better in some sort of light fitting where you cannot look directly at the globe.
Beleive me they are great.
greg

love life and still living

Bryan1

Guru

Joined: 22/02/2006
Location: Australia
Posts: 1344

Posted: 10:36am 04 Sep 2009

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Hi guys,
Dont bother buying 240 volt led lights checkout this circuit and the guy is not only a electrician but a decent guy on showing things not to do on utube. To check the voltage drop on a led just use the diode function on a decent Dmm. Thr 50 led's I got for $5 through Oatleys did provide a decent guide with forward voltage drop. 35 were 2.2550 volts 9 were 2 .45999 volts the rest didnt register but they did shine bright. My dmm is a fluke 865 and it preset on 3 volts so this weekend I'll try the rest on a 20ma current source to see if they are OK.

One thing if you are going to connect a heap of led's in series for AC use make sure you use a dmm to check the voltage drop.

Cheers Bryan

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 12:03pm 04 Sep 2009

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If I was to set up 12V LED lighting, I would be opting for a constant current source supply, rather than relying on a limiting series resistor.

Semiconductors often fail short cct. Take for instance a 12V battery and current limiting resistor sized for the 12V nom system. My battery when being equalized, has terminal voltage of 14.9V on a 12V nom system. Depending on wire sizing, and load connection point, the voltage could be higher. This could account for a current of 20mA set by limiting resistor, to actually be 20% higher. This will potentially damage a LED. worse case is LED's continue to fail, until the voltage across the resistor, exceeds the power rating.

Lots of LED's in series requires LED matching.

I have 7, 3W Luxeon 240VAC GU10 fitting LED lamps, and a bigger 10W Luxeon 240VAC Edison LED. These all have Aluminium heatsinked LED's, and SMPS in the fitting.

I have tested a lot of the different multi LED lamps, and the Luxeon have the more natural light. The myriad of 20-50 LED lights give an un-natural virgin white light. I prefer the sparkle single point type light of Luxeon warm white LED's.

A few resistors and an NPN transistor make a simple constant current source.

Gordon.

become more energy aware

MacGyver

Guru

Joined: 12/05/2009
Location: United States
Posts: 1329

Posted: 07:06am 05 Sep 2009

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I googled "LED lights" and came up with a good LED information source:

http://www.youtube.com/watch?v=TgphXf0qYeg

Give it a look-see. By the way, those LED bulbs are a bit pricey!

Nothing difficult is ever easy!
Perhaps better stated in the words of Morgan Freeman,
"Where there is no struggle, there is no progress!"
Copeville, Texas

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 07:55am 05 Sep 2009

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MacGyver said By the way, those LED bulbs are a bit pricey!

If you remember back when CFL's were introduced, the intro price of LED's is OK. I paid $22 ea for 11W CFL in early 80's. The $ is not worth as much now, so $40 ea for a top shelf 240VAC powered LED lamp is not that bad.

Gordon.

become more energy aware

Barry T Coles

Senior Member

Joined: 30/07/2009
Location: Australia
Posts: 109

Posted: 09:30am 05 Sep 2009

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Thanks heaps Guys.
Gives me something to work on.

Cheers
Barry

I need to learn from the mistakes of others.
I dont have the time to make them all myself.

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 11:50pm 05 Sep 2009

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Hi Barry,

Austria, or Australia?

Gordon.

become more energy aware

oztules

Guru

Joined: 26/07/2007
Location: Australia
Posts: 1686

Posted: 12:26am 06 Sep 2009

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Gordon.... his Coordinates: 20�44′11″S 116�50′47″E ... about 22m above sea level.

Mine are 40�00′S 148�07′E.... so he's where the water goes down the toilet the right way

Edited by oztules 2009-09-07

Village idiot...or... just another hack out of his depth

Barry T Coles

Senior Member

Joined: 30/07/2009
Location: Australia
Posts: 109

Posted: 01:16am 06 Sep 2009

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Australia

Thanks Gordon, a slip of the cursor one would guess & Oz was pretty close

actally 20 44 13.2S 116 50 45.6E @ RL 11.5m AHD.
Just checked the toilet for positive location identification & yes I am here

Cheers
BarryEdited by Barry T Coles 2009-09-07

I need to learn from the mistakes of others.
I dont have the time to make them all myself.

MacGyver

Guru

Joined: 12/05/2009
Location: United States
Posts: 1329

Posted: 02:10am 09 Sep 2009

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Barry:

I like your avatar!

Nothing difficult is ever easy!
Perhaps better stated in the words of Morgan Freeman,
"Where there is no struggle, there is no progress!"
Copeville, Texas

Barry T Coles

Senior Member

Joined: 30/07/2009
Location: Australia
Posts: 109

Posted: 01:17am 14 Sep 2009

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Thanks MacGyver

There's a heap on this site.
http://bestsmileys.com
Cheers
Barry

I need to learn from the mistakes of others.
I dont have the time to make them all myself.

Cornelius

Newbie

Joined: 26/12/2008
Location: Norway
Posts: 27

Posted: 06:46am 28 Sep 2009

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I'm working towards getting all the lighting in the house based on 12V leds. My living room are completely converted now, and the rest of the house use 220V led-bulbs.

There is a jungle out there regarding led-bulbs, and much of the cheaper ones are 'first generation' leds with a resistor in series with the leds; these doesn't handle voltage variations very much.

But the 'second gen.' leds are better; most of them have a small constant current controller embedded in the socket, and can often handle 8-30V.

Also, the Lumens/Watt are getting better; i would say that 70-120 l/W are good. The color temperature are also getting much better than the previous gen.; most of the better led bulbs today are available in the 2700K-3000K.

I got some led bulbs similar to the one Barry shows, but with 3x 3W leds and a temp at 2700K; not sure about the l/W, but it says 'similar to a 35W halogen'. Also, i just bought a bulb similar to the one Rep334 shows, but 220v at 8,1W with 82 l/W; excellent outdoor lighting.

Now, i bought these here in Norway, so i can't provide any useful links for shopping, but there seems like you are on the right track with the bulbs shown here in this thread.

Barry T Coles

Senior Member

Joined: 30/07/2009
Location: Australia
Posts: 109

Posted: 02:28am 02 Oct 2009

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Hi Cornelius

We are on the same wave length here, I want to be able to not rely on grid power for lighting.

I have been running the LED that I showed in my first post from a 12V 7aH battery for around 4 hours a night as a trial for direct lighting over the outdoor setting, its been there for three weeks now & there hasnt been a voltage drop yet.
If this is an indication of the sort of usable low votage lighting I am going to get then I think I will be happy with a full house installation.

Cheers
Barry

I need to learn from the mistakes of others.
I dont have the time to make them all myself.

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