Xhp70 driving problems

Hi guys,
I have ordered a Kaidomain 1-mode driver for my Xhp70,
wich i`ll be using in my new dive torch

The drivers input is 4-18v
The driver is suposed to provide 6v @ 4,5-5Amp.
I tested it with a power suply(15A max., 15v), and also 3 Panasonic NCR18650B(3400mAh) in series

well.... the driver is giving my led the 6volts, but only 2Amps, wich drop down to 1,6Amps after about 40 seconds runtime.
The same situation repeats on the power suply as on the batteries

Has anyone an idea why the driver isn`t working as it schould?
Thanks to you
Regards
Mark

Hi,
I have thought about that!
It might explain the drop from 2A to 1,6A after some run time,

but in my view this does not explain the inicial 2A when cold. (should be 4,5A minimum)
After testing it the first time, i waited about 30 minutes to ensure the driver was room temperature to test again, and the result was again a maximum of 2A current on the LED.
Has any one a nother idea?

Probably they just sent the wrong driver.
Thanks
Mark

How good are your multimeter leads? Try with pieces of thick wire instead of the leads.

you can tray ''load'' resistor instead of led : P=3,7V*5A= 18,5W ; R= 18,5W/25 ohm = 0,74 Ohm to test driver. Voltage drop U= 3,7V @ 5A.

thick wires ( from multimeter ) are good suggestion , I use clamp A meter.