inst. panel LED warning.

[oregon-mike]

Yaric08,
You may want to check out that site again. The way I have read it is that those power pucks will run the LEDs in parallel as well as series. I've been looking at the Luxeon K2s for exterior & interior lighting in the horse trailer. I'm going to order a few of them and see how well the puck does for powering as well as see how bright the lights really are (do I *really* need 12 of those things on the outside & inside to be able to see at night?).

Here's the page with the power puck I'm looking at (they don't offer a 1.5A one for max brightness on the K2 yet):
http://www.luxeonstar.com/item.php?id=863&link_str=240::241&partno=3021DE1000

There's a link on that page with the data sheet. Here's the portion I'm talking about:
Figures 3 through 6 show 700mA and 1000mA rated units driving multiple LEDs. Note that parallel strings of LEDs can
be driven directly with no additional circuitry required to insure current sharing. The nature of the LEDs themselves
will provide good current sharing if the parallel strings comprise 3 or more junctions each.

Now I, so far, have yet to find on that page exactly how *many* strings in parallel that puck will run, but I'm hoping for 4 of them. Those K2s drop 3.85 V per LED. I'm going to try to run 4 parallel strings of 3 K2s in series for the lighting I want to accomplish on the outside/inside. First order of business is getting half that amount and seeing if the puck will drive 2 strings and see how much light I actually realize. I'll be using the spot mounts and the lenses as well. They only claim 85% of the light out of the lenses, and I'm already only getting 66% of the light based on the current I'll be feeding it (1A vs 1.5A).

I'll start a post later if anybody's interested in the results.

Mike

 

[tonkadoctor]

Heres something to consider with the voltage in a 12v automotive system that puts out usually 13.5 - 14.5 volts and can be more or less depending on the condition of the charging system and the load placed on it.

When I started replacing my marker lights as the burnt out I noticed that the automotive replacement LED lights have a small circuit board with more than just a resistor on it. I didn't look close at the micro components, and prolly could'nt read them if I tried without a microscope, but I would venture a guess that one of them is a voltage regulator to keep a constant voltage to the LED as long as the supply voltage is between a certain range.

 

[yARIC008]

Yaric08,
You may want to check out that site again. The way I have read it is that those power pucks will run the LEDs in parallel as well as series. I've been looking at the Luxeon K2s for exterior & interior lighting in the horse trailer. I'm going to order a few of them and see how well the puck does for powering as well as see how bright the lights really are (do I *really* need 12 of those things on the outside & inside to be able to see at night?).

Here's the page with the power puck I'm looking at (they don't offer a 1.5A one for max brightness on the K2 yet):
http://www.luxeonstar.com/item.php?id=863&link_str=240::241&partno=3021DE1000

There's a link on that page with the data sheet. Here's the portion I'm talking about:
Figures 3 through 6 show 700mA and 1000mA rated units driving multiple LEDs. Note that parallel strings of LEDs can
be driven directly with no additional circuitry required to insure current sharing. The nature of the LEDs themselves
will provide good current sharing if the parallel strings comprise 3 or more junctions each.

Now I, so far, have yet to find on that page exactly how *many* strings in parallel that puck will run, but I'm hoping for 4 of them. Those K2s drop 3.85 V per LED. I'm going to try to run 4 parallel strings of 3 K2s in series for the lighting I want to accomplish on the outside/inside. First order of business is getting half that amount and seeing if the puck will drive 2 strings and see how much light I actually realize. I'll be using the spot mounts and the lenses as well. They only claim 85% of the light out of the lenses, and I'm already only getting 66% of the light based on the current I'll be feeding it (1A vs 1.5A).

I'll start a post later if anybody's interested in the results.

Mike

yeah, i realize you can use the power pucks in series and parallel with the LEDs. The way i have it figured though i need at least two of them because you have to exceed the voltage drop to the power puck in the voltage in. From their site - DC input voltage from 5V to 32V. (The input voltage must be at least 1 volt higher than the forward voltage drop of all series connected LEDs.)

So that's pretty much a max of 3 LEDs per puck and i need five for the instrument cluster. So that's 60 bucks just to power them, after i spent 100 just for the LEDs.

The cool thing about those power pucks though is they have a dimmer feature on them and i believe you can just use a standard dimmer to control it.

 

[445TDF-series]

Wow those are some expensive LEDS... i think i may stay with the ones i have... I'll see what i can do to wire them up w/o frying... I may buy one of those fancy ones and see if there is a big difference...but right now the truck has bigger issues... Curious how the LEDS i have now will fare though... thanks for the help!!

 

[86 1 tonhauler]

i wouls never go with leds for dash light for one there hard to get to dim and two there probably to bright so they will be blinding u and three really tell me how often to cluster bulbs burn out " they burn out very very rarely unless ur voltage regulator goes bad and u get a high voltage spike and they blow but still
i have an old 86 and had an 83 s-10 with 300k on it and never had to replace a bulb in the dash

 

[445TDF-series]

I should have specified...i may do the leds for the warning lamps, not ones that dim. The illumination will be the bulbs. I just can't see the darn wrning lights when they come on, which usually isn't too often... good thing. But since the dinger doesn't come on when something is wrong, it is hard to tell.