KD Driver Issue

Flashlight Modding and DIY Parts
1

Hi all,

I bought this driver from KD and am having an issue with it's high mode, so I'm wondering if anyone has firstly used this driver and secondly if they are aware the problem I appear to be having...

Firstly I'm using this in a 6D maglite (9V total) to power a 6V MT-G2. The light functions well on low and medium modes (though it takes a while to actually react to my switch) but when I turn it on high it runs for 2 or 3 seconds but then it drops to medium for half a second, then back to high for half a second, and then repeats. After 2 or 3 times doing this it then goes high, medium, and not-quite-low, and then repeats this behavior until I turn it off totally. When I say not-quite-low I mean it goes slightly dimmer than medium but definitely not low.

It can't be the low voltage protection as firstly the batteries are brand new and secondly it's not the behavior the KD page states will happen in a low voltage condition.

It's odd. Is it the driver bust or am I using it incorrectly?

Any suggestions would be appreciated. This build is not for me but a friend and I'm trying to avoid buying a new driver, though if it comes to that I'm happy to hear some recommendations.

Thanks,

- Matt

2

try feeding a couple of li-ions and see if it operates normally, I’m wondering if the cells are sagging under load.

MrsDNF reported its slow on its mode changing I seem to think, I think he’s using it in his defiant build.

3

Hmm, I wouldn't think D cells would sag under as little as 3A but I'll try and then report back.

4

It was the IOS driver that was slow on the mode change. The IOS will do something similar to this problem when the voltage is to low. On the Defiant 3C light I recently modded I had trouble driving the IOS driver with one King Kong at just over 5 amps. It would jump all over the shop with 4 C cell batteries.

I have this driver in my 2 x 26650 HD2010 and it pulls over 6 amps on high and 5 amps on med using it on a single XM-L led at the tailcap. I dont know if all the KD drivers are like this or just the one I have.

Comparing the two drivers, apart from the slow mode change on the IOS one I much prefer it over the KD driver because the current output is more sensible using a single LED.

5

Well using 2 brand new Panasonic NCR 18650 cells it works fine.

I don't understand how the D-cells can be sagging. I've pulled 4.5A from 3 D-cells in the past no worries (single emitter).

This driver provides 5A to a single emitter (lets say 3.6V) or 3A to a string with a voltage of between 10V and 14V. So how is it going to behave with a single 6V MTG-2 emitter?

6

hard to say, , I’m driving an mtg-2 with this one I read 3.something amp at the tailcap, not sure on emitter amps tbh but these mtg-2’s seem to be current hogs if you let them. Maybe you could run it on a series/parallel eneloop setup in d size holders.? or tenergy d size nimh cells?

7

The specifications and physical appearance of that driver and the one I am using suggests to me these are from the same family. Hell that one is called the FL-2 while mine is the FL-3.

I think I'm going to have to hunt around for a higher quality board...

8

I replied to your thread over at CPF. If your using Alkaline cells they will sag horribly under load. Nimh will do a much better job under load.

9

Yeah thanks for that. I posted and went straight to bed - I was fed up haha.

I'll have a look around for replacement cells, and weigh up the pros and cons of switching cell types or the driver itself.