Noob needing help with a flashlight repair

[Raftingtigger]

Hi all,

This is my first post at CPF, and CPF was suggested as a resource from ScubaBoard members. I'm an accomplished DIYer, but my electronics knowledge is limited to soldering and remove and replace. I've done a quick perusal through the forum, but don't have the knowledge to see if there are approximations to my question(s).

I bought a http://www.linkdelight.com/DC080-200m-Underwater-Diving-CREE-XML-T6-LED-Torch-Flashlight.html and loved the light, but found the switch unreliable. To make a long story short I now have a nice light that I can't turn on. I have managed to completely disassemble it. A complete and ongoing discussion (with pictures) of the innards is found at http://www.scubaboard.com/forums/li...w-how-dismantle-1000-lumen-chinese-light.html

ScubaBoard is predominately divers that some dabble in lights. CPF is probably light enthusiasts that might dive. I think that is what is needed at this point.

My goal is to make the light functional, even if that means ON/OFF is putting in the batteries while above water and removing them after the dive.

An alternative solution is to increase the luminosity of the lights currently on my GoPro tray. They are http://www.linkdelight.com/DC079-20m-Underwater-Diving-CREE-Q3-LED-Torch-Flashlight.html I really don't want to buy anything from them anymore.

My two questions:

1. Any suggestions to fixing and or replacing the led circuit board and or module for the 1000 lumen light.
2. Can I replace the 180 lumen led with a higher output one using the same module for the yellow lights?

Thank you, Raftingtigger

 

[AnAppleSnail]

First step to repair: What is broken?

Put the batteries in. Wave a powerful magnet (Do you have one of those rare-earth ones?) near it. Does some position activate it and leave it on? If so, the hall sensor works and the current magnet does not. In theory, any ring that holds the magnet still until you turn it will work to replace that. If the hall sensor is damaged, you'll have to fix that. I do not know how to do so.

 

[Thr3Evo]

My two questions:

1. Any suggestions to fixing and or replacing the led circuit board and or module for the 1000 lumen light.
2. Can I replace the 180 lumen led with a higher output one using the same module for the yellow lights?

My two cent two answers:
1. Find what the diameter of your existing board is, and find a 3 amp(or close to that) buck driver(because the light runs on two cells) and make a direct replacement by soldering the wires to the new board. See shiningbeam, deal extreme, kai domain or international outdoor for starter to see if they carry something for your needs, if not search here or maybe someone else can recommend a better place.

2. Ask the supplier for the specs of that driver and how those batteries are used(series/parallel)...so you know how much voltage and current you are working with and then maybe come back with that info....
It's probably going to be a pain to mod that light tho, any emitter that will provide more light will also provide more heat and drain those batteries with the quickness.

 

[DIWdiver]

Definitely the broken part is an inductor, not a magnet. I don't know how many of them I've replaced doing repairs. With that much of it missing, it will not make the light intermittant, but if the light continues to work (which it seems to, at least now and then) it will very likely make it less efficient, so it will drain the batteries faster.

I agree with the previous posters as well. My magnet-ring light has seen the magnets start to disintegrate after being in salt water. It also tends to collect iron dust from wrecks, which short out the magnetic fields. Fortunately, those can be cleaned off. It still works, but I know I'll eventually have to replace the magnets. And a few tests to see what's actually broken can help tremendously in fixing it.

A 2.8 or 3 amp driver from the sites mentioned above would do a good job if you could fit them in the light. They might be sold as P7 or X-ML drivers. The problem you'd have is the switch, as you already know. If you find a driver that fits, it's conceivable that you might also find a reed switch that fits and could be activated by the magnet. The dimensions don't look promising, but keep a positive attitude and all. Also, none of the sites mentioned above sell any higher quality product than where you bought the light in the first place. I take that back. I don't know anything about International Outdoor.

Taskled makes a hall switch board that could help, but again the dimensions don't look promising.

While you're at it, you may want to consider changing the o-rings in your light. The really low-cost lights have notoriously poor o-rings.

 

[Raftingtigger]

I'm learning more, but not there yet. This is what I've gleaned so far about my broken light.

LED is a Cree XM-L T6 with a max output of about 1000 lumens at 3 amps, and about 290 lumens at 700 milliamps.
Batteries are 2 18650 cells in series for about 8.4 volts Figuring that the driver delivers 1/2 that voltage forward I tested the LED driven directly from 3 AA batteries in series (4.2 Volts). It worked - very bright. So my LED emitter is good.

The Hall sensor (magnetic switch) appears to be a Winson WSH315 (Linear Hall Effect Sensor IC: Features:z Wide operating range 3.0~12V, -40℃~125℃ z Wide output voltage range 0.2~4.8V (at Vdd=5V) ±1,500 Gauss on 5V supplied voltage). Center contact connects with the negative battery terminal. Vdd connects to the positive battery terminal sometimes. I then connected the negative battery terminal to the circuit board terminal and the positive battery to the emitter positive terminal. This gives me a weak light. Clearly something in the ground circuit of the driver board is lowering the current, but not the voltage (tests as 4.2V). I get no response to the magnet touching the Hall sensor either with or without the power on.

Conclusion: I have a bad driver circuit and possibly a bad Hall sensor.

Solutions:
1. Find a replacement driver board that has the same Hall sensor location (haven't found one)
2. Install a driver board that has the switch permanently closed and turn the light on/off by putting in the batteries - not my favorite idea, but the simplest to do.
3. Install a driver board and use the head for the start of a can light - intriguing idea - I could even mount the larger battery pack under the GoPro as a stabilization weight. Since this is a longer DIY project...
4. Install a driver board and install a mechanical switch into the tail cap. I'd probably have to find a waterproof push on/push off to fit in the space available, although a toggle with a waterproof cap is my preference.

IDEAS anyone??? Point me to other threads? Suppliers? (DX looks intriguing) I even thought about taking the Cree XM-L T6 and moving it over to the 180 lumen light (I have 4), but wonder about the heat dissipation and battery life. Might melt the plastic housing of the light even in the water

but then again DX has a 1000 lumen diving light in a plastic housing for $15.50.

For the wonderful people who have posted some suggestions -- a few more details: the 1000 lumen light I'm trying to fix uses 2 18650 cells in series. driver board diameter is about 20mm (I don't have my notes with me) and there should be many choices at DX. The light I might increase luminosity in uses 4 AA cells in series. I don't think I would use a 1000L emitter, but maybe double what it currently has. In that case I would just swap the emitter and star and leave the driver alone. I run time of 60 min would do, and 2-3 times that is more than enough.

Lastly, any ideas for a SMALL mechanical waterproof switch that could be installed in a tailcap?