1000ma

[cannondalecaad]

I recently purchased a light, a MX Power Cree Q5 180 lumens it said it was regulated 1000ma but when I checked it for amps it says it is pulling 1.5 on hi and 450ma on low beam does this mean that on high it is pulling more than it should ? could the driver board be bad ??? this was checked with a 18650 bat it runs a 1AA or 1 CR123 3.7 is it pulling more because of the battery or not?? I am new to this stuff so sorry if this is a stupid question.

 

[Norm]

The 1000mA will be to the LED, because the driver isn't 100% efficient you are measuring 1500mA at the tail.
So everything is OK.
Norm

 

[cannondalecaad]

Thanks that helps! so do I need to disconnect the led and check that to see what it is actually pulling or is there another way to do this.

 

[yellow]

I see that different:
when You measured 1.5 A at an 18650, there is definitly something wrong!
As Led and Batterie are pretty much the same voltage, the input current is very equal to the led current.
(no need to solder around at led, rough guess is enough. If You want to check with current meter, sure You may)

let the light run for 10 mins and then check, again after 1/2 hour and 1 hour.
Possibly its just high initial current.

could the driver board be bad ???

every cheapo from DX is "bad", the question is, what measurement one uses:
Thats mostly very, very cheaply made - often copied form "better" makers, or at QC rejected parts, ... something like that - and do have some negative points.
BUT most of them at least work and those special points (reliability and machining to be concrete) is something one can learn with some time of usage ...
... then switching to other makers - more realible, better made, but thus costing more.



PS:
18650 is Li-Ion, CR123 is about similar.
AA cell is only 1/3 of the voltage, so would need 3 times the current for same led power

 

[HKJ]

I recently purchased a light, a MX Power Cree Q5 180 lumens it said it was regulated 1000ma but when I checked it for amps it says it is pulling 1.5 on hi and 450ma on low beam does this mean that on high it is pulling more than it should ? could the driver board be bad ??? this was checked with a 18650 bat it runs a 1AA or 1 CR123 3.7 is it pulling more because of the battery or not?? I am new to this stuff so sorry if this is a stupid question.

My guess is that the light has a boost only converter. When you uses a 18650 the voltage is higher than the Vf of the led and the light goes into direct drive.
I have written about different types of drivers here.