Defective rechargeable floodlight

Thanks for the input.
There are 12 cells indeed.

Going to try the second one.
Rather have the light turn off before completely empty than to burn stuff. And since the driver is enclosed in the battery compartment cooling is an issue.
My friend is using the light while working. Don’t know if he will be attentive enough to notice the light needs to be turned off because he works with multiple lights at once.

What would be a nice voltage to set it on? Since the led runs from 30-36V. Lifetime is more important than brightest output so putting it on the lowest as possible? Or a little higher, at 32V so it has some margin of error?

With an adjustible boost, you might let heat be your guideline.
Crank it up so the light is bright enough without producing too much heat to cook things.

I wonder about the battery pack and charging.
It might be worth a look to see how the cells are aranged.
And if any cells seem out of ballance.
Looks like you are getting close to solving the puzzle.
All the Best,
Jeff

I think your friend will notice that the light is discharged.
The output power of the driver drops to 40% at a voltage of 9.80V. Then the brightness continues to slowly decline and can reach up to 20 lumens. Such brightness no longer illuminates anything, and it will be clear that it needs to be charged.

A few steps to configure the driver.

The driver has 3 trim resistors on board
“CC” (Voltage Regulation)
“CV” (current control)
“UVP” (Adjustment of undervoltage protection)
First you need to rotate all adjustment resistor counterclockwise 20-25 turns, at the end you can hear clicks.
Connect the driver as shown in the picture.

Turn the “CV” adjustment resistor clockwise and adjust the voltage to 32V.
Then connect the driver as shown in the picture.

Turn the “CC” adjustment resistor clockwise and adjust the current to 1.10A.
Slowly turn the “CV” adjustment resistor counterclockwise until the current drops to 1.08A, then slowly turn clockwise until the current rises to exactly 1.10A. At this point, the adjustment is complete.
Thus, you set the power to about 35 watts.
I think it will be optimal for runtime and brightness. If the brightness is not enough for you, you can increase the power, but I do not recommend increasing it more than 50 watts.

A few points:

  1. I do not recommend using, or turn on the light while charging.
  2. Do not enclose the driver in silicone or hot glue. You need to drill 4 holes and fix the driver to the screws, or wrap it with something and fix it with silicone to the back cover as the batteries are fixed. I recommend checking the silicone seal on the back cover.
  3. In the undervoltage protection mode, the light will not behave stably (nervously), this is normal.

I hope this helps you.
Waiting for the result…

Thanks for the input again!

The light works! But don’t know if it works as supposed. Don’t know how bright it was before and if this is what it’s supposed to be but the numbers aren’t right.
I can’t get a higher Amp output of 0.45A

I did as suggested. Dialed it in at 32V without load. Connected the light, it starts at 0.45A and no matter how far I turn it it stays there. The voltage stays at 28.6V at the output leads. I turned it all up until the clicks but that’s the maximum I get.
I measured voltage at the input leads and it’s at 9.8V. So I assumed battery pack was defective after all and it went into protection right away. But then I measured at the battery pack itself during the same time and it’s at 11.9V
To rule things out, I connected it to the 12V lead acid battery, and the 12V 6A powersupply and the exact same results.
Around 0.45A and 28.6V output. A measurement of 9.8V at the input side.
I tried to see if I can change some values if I change the UVP resistor. At some point the light turns off, measured voltage shoots to 12.4V so I assume the undervoltage protection is set at above 12V at that point.

Oh, and I wish I could get the battery pack out, trying to measure cells individually. I tried but it’s so glued to the case I’m not able to get it out easily. No space to get under it. Tried to wiggle to get it loose but no luck. I’m afraid to damages the cells if I try something else. Tried to put a spoon on the side to have some leverage but it looked like I was going to dent and damage the cells if I used any more force.

Try to pry it off with a hard plastic item, for instance an old creditcard or old membership card or equivalent.

Yes you are right, the driver works in protection mode.
Turn the “CC”, “UVP” resistor fully counterclockwise until it clicks. Connect to a 12V 6A power source or lead battery and try increasing the output current again.
And do not short-circuit the driver output.
With an input voltage of 12V and an output power of 35 watts, the input current of the driver is about 3.20A. This should not be a problem for a good lead battery or 12V 6A power supply.
The minimum value for undervoltage protection is 9.80V, you cannot set it lower, but you can set it higher using the “CV” resistor.

To measure the cells in the battery you need to remove the blue film. In this case, it is not necessary to tear off the battery from the cover, you can cut the film gently and remove the cells.

It’s strange.
I began to doubt, maybe the old driver is working.

Just tried again. Same results.

12V 6A power supply.
Dialed everything CCW until clicks.
Connected PSU, ramped up voltage to 32V, measured voltage at input 12.1V.
Connected light. Slightly turned up CC, lights goes on at 0.4A, immediately voltage on input side drops to 9.8V.

Am I unlucky? Do I have ordered a defective driver? Should I just give up :confounded:

This is really weird.
Can you show the photo:
new driver (on both sides),
connection photo
12V power supply
Lead battery.

It’s too early to give up

@RD, your English is perfect. Most of us don’t speak 2 or more languages, so you are doing great.

@johnny, you have done a great job at troubleshooting. Considering all the strange results i would recommend a simple approach to start at the input and work to the output.

0. Remove all the goo and glue around the connectors and switch and any other place in which the wiring solder joints are covered. Inspect and touch up any cold or broken solder joint. Replace wires if necessary to ensure good path and eliminate the wiring or joints as a culprit.

1. Slice the blue film so you can verify the configuration of the cells, to measure and compare the individual cell voltages (looking for laggards), to load test and check capacity of individual cells, and to look for some sort of BMS board for the cells.

2. Rebuild the pack (replace defective cells) and BMS as necessary to eliminate that as a culprit of the problems.

3. Charge the pack and measure/verify the voltage and current while charging, if possible. Measure the pack voltage after charging to verify that the charger is working properly, no over or under charge, cuts off at limit, etc. Eliminate the charger as a culprit. [and like RD said, don’t try to run any load from a charger, not designed to work that way and possible to damage something.]

4. Test the driver and LED with this known-to-be-good pack. If the results are flaky with good solder joints, wiring and pack, then the driver is suspected as a culprit. Repair or replace.

5. Now the light has been rebuilt from front to end, and should give good service, especially considering the price.

Here is just an example of some various drivers: open boards, enclosed, and waterproof.

Good Luck and Enjoy.

The wiring looks like a mess but I know where everything is going. Don’t have any better way of attaching everything and being able to switch to the different parts and power supplies easily.
The 12V lead acid photo will have to wait if necessary. Put it back in the storage downstairs of my appartment building. It’s an 12V 12AH battery used in a mobility scooter. I believe from powercell.

@Kenny
Right now I’m not dealing with any solder joints. I have taken everything apart as far as possible to have quicker and more room to work with.
In this I have fully eliminated the switch and charge port.

Don’t know if I am able to rebuild the battery pack. I can try and slice it open, but there is not much room on one side to measure things. Sure can’t measure the bottom row without touching the top row without taking the whole battery pack apart.
But since it’s not working properly with the power supply I think I can hold of messing with the batteries until that issue is resolved?

Your mistake is that you use wires that are too long on the driver input.
Connect the driver cable directly to the connector as shown in the picture, and try to adjust the driver again.

The battery in your current meter is indicating low and should be replaced.

The red lead on the current meter is cracked and broken right at the strain relief. This could be a high resistance junction or go open intermittently causing additional issues.

I forgot to add, the driver output wires to the LED should be as short as possible. I recommend to remove the factory probes (wires) of the multimeter, and connect with short good wires as shown in the photo.

I see some soldering defect, I recommend cleaning it.

A photo of a lead battery is not necessary, if it is used for a scooter it can give a lot of current. I wanted to see why this did not help you.

And for the future.
When measuring current, it is recommended to use as short wires as possible and short connections. Otherwise, you may get a big measurement error. Factory probes (wires) of the multimeter are not always suitable for measuring high currents
For a better current measurement, I recommend buying a “banana” plug and soldering short thick wires to them.

It will also allow you to measure high currents of flashlights.

And as @ Kenny said it’s better to replace the multimeter’s battery later. With a low charge, the multimeter may give incorrect values.

I have a question. How did you connect the old driver? If you connected it through long wires, maybe check it again?

Oops. I figured the quality of my test materials would influence the readings, all cheap chinese stuff. Didn’t figure it could have this much impact.
I do have a lot thicker wire, even thicker than the regular pieces of wire I stripped out of a 230V power cord, and a LOT thicker than the wires inside the alligator clamp leads.
I’ll make some better equipment.
I have some banana plugs lying around used for a stereo. It’s also cheap chinese stuff. Would it work and be good enough if I soldered the thick wire to it? Otherwise I will order real multimeter plugs


Also found these, if it works these might be better quality?

The second ones look good. They also have a screw, that can fast connect the wire without soldering. You can try using thick wires with a length of about 300mm. In any case, it will be better than the factory probes.
But if the covers are metal, you should be careful with high voltage measurements.

Alright, this is my new test equipment. Will need to redo it. The alligator clamps lost their clamping power. Probably have overheated it. Also replaced battery in multimeter.

Also replaced the wires going to the LED with this thick wire. Might try to rewire the battery pack but don’t know if I’m confident enough to do that.

With this new short leads, the light works! Can amp it up a lot more. Way brighter. Only thing I still noticed is the output seems to hang at 28V, might be my multimeters? But tried both.
With the 12V 6A power supply the light has an awful amount of flickering. Almost nauseating. This does not happen with the battery pack attached.
Also tried the old driver. It works………Draws 0.68A, output of 28.8V, nothing to adjust here. Didn’t replace any more wires here so still the very flimsy thin wires on the output.
So…. Don’t know what to think of it now. Battery pack is the culprit? And with the newer thicker wires it is able to draw more and keep up?

Good. It looks like the Alligators are a bit overheated.
Voltage 32V-36V for COB LED is for reference only. It does not matter what voltage you get on the LED, it matters what current you give to the LED. It’s hard to explain. You can see the electrical characteristics of the CREE XML2 LED, other LEDs behave in a similar way.

What current did you install on the driver output, and to which battery did you connect the driver?

Johndoe

What power supply are you using? is it AC or DC? Ac will result in a flicker of 25 Hz of course

It’s an AC/DC adapter.

I stopped at 1A because I did not know if I could trust the voltage output and didn’t want to break anything.
I connected it to it’s original battery pack. So in this result with the old driver everything essentially is connected as it was in the first place, but with some better cables and without switch and charge port.

Next step is to hook it up to its original connectors again, with the added better wiring as far as possible. Maybe my out of the device testing with the bad long wires has thrown all issues to another point and the switch is defective in the original issue.

You have done a lot of work with this light.
The old driver gives out only 20W of power. Original wires may be enough, but if you want you can change.
If the old driver will work and only the switch is faulty, you have a few steps left.

- Fully charge the battery, and check the runtime.

  • Compare this light with others that your friend has.

But we learned that this light was sold as 100W, it looks like 50W, and works on 20W. Marketing.