Problem with 4.5A driver with series LED ~~~ need some advice ~~~ I got modes! Yikes! Now I have none!

Flashlight Modding and DIY Parts
1

I'm in the middle of modding a Tansfire 3XU2 and am having a bit of a problem that I'm not sure how to go about solving.

I swapped the LEDs with XM-L2 U2 on Noctigons wired in series with an IOS 4.5A driver Powered by 3 x 26650 KingKongs In series.

When I turn it on it works, but only one mode. The reading at the tail is 4.5A, but I can see it dropping. At first I thought I might have accidentally jumped something and am getting direct drive, but with 3x26650 wouldn't the reading be much higher?

I turn it on and get a solid output, but after about five seconds it starts flickering. Not flashing, but a visible pulse like a disorienting PWM. The light is still full brightness, but pulsing.

Can anyone advise me on troubleshooting.

PS. The light is friggin bright and I'd like to get it running right.

2

I picked it back up and it’s not pulsing anymore. Maybe it was just a glitch.
I did notice that the switch retaining ring unscrews itself when the tailcap is removed. I retightened it.

The drivers spect say 12V, so technically I’m running 12.6V. I don’t know if that matters. When the pulsing stopped, I checked the cells, and they were at 4V.
I’ve got them on the charger to check them again at 4.2.

I want my medium and low back. This light gets hot real fast on high.

3

I recharged the cells back to 4.2V and the pulse has not returned.

4

Mayby better to change the driver:

Xandre

5

It’s the same driver except mine is 4.5A. 3 LED at 4.5A gets hot really fast. 5A would kill the cells even faster.

6

Do you think that your ground connection is solid? It sounds like it may be a grounding issue, or a faulty driver.

7

I can’t think of anything else to look at but ground. I just hate taking it apart after it took me all morning to center the emitters. If it’s a ground problem I would have thought that I would be reading higher than 4.5A on direct drive.

Until then I’m going to play with it tonight as is. It’s friggin bright and the outside temp should help with the heat.

8

The flickering is why I suggested either bad ground or bad driver. I can't see it being much of anything else (the flicker).

9

It could possibly be the driver overheating. The temp protection on the 9 amp IOS driver was supposed to do all sorts of fancy things to protect itself but did nothing like advertised. It would go into a slow strobe and be stuck on high only allowing me to turn of the light. Turning it back on instantly it would do the same thing. Letting it cool down awhile the light would function correctly but after awhile it would start the same overheat cycle again. Good luck.

10

The pulsing stopped after I tightened down the switch retaining ring…I don’t know why. The driver is 19mm sitting on blob of Fujik in the middle of a 32mm board.
Maybe it is the driver. I’ll run some tests tomorrow.

I think TomE used this driver in a BTU Shocker.

11

Cool. So the pulsing probably was bad ground...now the issue of no modes.

12

Unscrew a bit the switch retaining ring and see if flickering is back!!!

13

Well, I used the driver when sold from IOS? Pretty sure that was 4.5A - he went thru one upgrade. Yes - you have the same setup and it goes direct drive, but modes always worked.

14

I got three modes…and now it’s not working.
I pulled the driver and looked it over, everything looked fine. I reinstalled it, turning the the opposite way to coil the internal wiring. It wouldn’t work at all.
I pulled it again and reinstalled it by twisting the other way…three modes.

Tail cap measurement shows Low- 0.12A Med-1.3 A and high starts out at 4.9A and kept dropping. At 4.3A it went out. I thought maybe it was a heat cutoff, but it’s been outside on my balcony in freezing temps and won’t come back on.

15

faulty driver I would say!

16

Thinking I had 1 or 2 bad - not sure if I was the cause or not...

17

Well I pulled it again and played with it and can’t get no satisfaction. Unless an emitter wire came loose it must be dead. I hate having to pull the reflector since it took all morning to center the emitters.

18

I removed the reflector and found one of the emitters is fried. I guess that would explain why the series isn’t working, and I don’t have anymore U2 1A emitters left.

19

Well, a wasted day. I touched battery leads to the emitters to test them. One was dead and the other two gave a quick flash. I tested again, and they were all dead.
I wasn’t thinking and forgot I had two cells in series from testing the driver. I guess just momentary contact was enough to kill them…rats.

I guess this mod is on hold until RMM can get me some new emitters. I might give the dry driver a try on my next go.

20

I had a similar day a few weeks ago. Had a rare day to kill and spent it working on a mod I had been planning for a while. One thing after another went wrong and by dinner I had to put it aside (to keep myself from tossing it out).

I came back to it a week or two later and now it’s one of my favorite lights. All part of the fun!