Why does my MCE light come on ?????

[H20doctor]

this is my soon to be light of death.... each mce has its own 700Ma luxdrive driver... Now it should not light unless i have 14.2 volts going into it ?? right??
well guess what it lights up when I put 1 utrafire 18650 3.7 2400 ma battery on it.... why ? does it come on ?

yes i am a newbie and yes i dont understand voltage..

2nd question..... How long will this light burn with 6ea 18650 ultrafires 2400ma ....

 

[Dr Jekell]

AFAIK most LED's are able to utilise under voltage quite happily but it won't be @ the full brightness that the LED is capable of.

Someone who is more knowledgeable than me will pass by soon.

 

[H20doctor]

Ok thanks dr j.. We will wait

 

[H20doctor]

Any one ??? Hello ...

 

[divine]

How did you wire the LED's?

All in parallel?

I'm guessing you wired all of the terminals on one side to one wire and all of the terminals on the other side of the led to another wire. (Parallel)

The driver is putting out 700mA to each MC-E (this is pretty underdriven) or about 130mA to each of the four die. In reality, each MC-E will be a little brighter than a normal Cree at 700mA (which isn't even high for a single die).

I guess it depends on what the driver is looking for on the input side.

Can you give us a link to the driver you're using?

 

[H20doctor]

http://www.ledsupply.com/03023-d-n-700.php

The dies in the MCE are in series..
1 driver to one MCE ..

Here is how its installed
http://m.flickr.com/photo.gne?id=3020400859&

 

[yellow]

possible that Your Step-down driver goes into direct drive mode, when input voltage gets too low.
Still wondering that the ME-C lights up. You are right: it should not
is it bright?
did You measure current from battery?
I could also just guess that the MC-E must be wired in parallel to light up brightly but You certainly would see that wiring on the star and did state it is series.

2nd question..... How long will this light burn with 6ea 18650 ultrafires 2400ma ....

6 cells?
Sounds unusual, how do You want to wire them?
With 6 in series, the three MC-E light @ 700 mA should run for :thinking: about 1.5 hours.

(expl: 6 cells in series is 6/4 the voltage needed --> thus 700 mA equals for ~500 mA draw on batt pack. Three times that and a single cell has 2200 mA.
Losses are exaggerated)