cant find the answer

Hi once again my friends

trying to find the answer but cant find it in any if the posts i have searched

my question is

are the Amps i get at the tail cap the same as the driver is giving to the LED

i have put XM-Ls in a few lights i have but dont want to change the drivers if the ones in the lights are already as good as the ones i have

cheers Barrie

Basically yes…although the amperage at the led will be slightly less from driver efficiency loses…or so I’ve read…

On average about a 20% difference between what is measured at the tailcap and what is delivered to the emitter.

If you have a single cell light, then the above is roughly true for linear regulator based driver (eg 7135 based).

When you have multiple series cell lights, then the tail cap current may be a lot less than the LED is receiving. This is true whether you are running a buck driver or a linear regulator driver

Tailcap current will be within a couple percent of what the emitter is getting with linear drivers, regardless of voltage.
Switching drivers, will have a current flow that is very dependent on the voltage, following an inverse relationship if its running within its design voltage range (i.e. In regulation)

What batteries are you using?

in my tank-tk 566 1x 14500 or 3xAA NiMH with extension tubes

in my ultrafire A10B 1X 18650

i ask this because KDs sent me 1.4 Amp drivers instead of 2.8

and the ultrafire is pulling 1.5-1.6 at the tail so no point changing the driver if it is already at 1.4 Amp or above

You could sacrifice one of the drivers and remove the 7135 chips and stack them on the other driver making it into a 2.8 amp.

Not my crazy driver but just so you get the idea.

thanks for the help guys

and thanks for the suggestion E1320

i think it is best that i wait for the correct drivers to arrive my soldering is nowhere near that good