Keeppower Protection Circuit Issue

md17

Newly Enlightened
Joined
Oct 28, 2023
Messages
190
Location
usa ct
What are my other options that aren't primaries in an md3 sized body? It's really that size that I like the best. I have a cr123 spacer and can use an 18650, but that won't give me full output with a hound dog.
 

F89

Flashlight Enthusiast
Joined
Mar 15, 2014
Messages
1,420
Using 2x18500 is a perfectly cromulent choice, so I don't think it's unreasonable for you to stick to your preferred option.

At this point, you've put in a fair amount of effort and received plenty of decent feedback, so if the new 18500s you have on the way play up then I can only assume that the light most likely needs to be sent back to Gene for evaluation.

Whatever the case, I'm certain you can get your MD3 running with 2x18500 and the heads you mentioned.

I hope this gets a solid solution/conclusion to the issue for you post haste.
 

knucklegary

Flashlight Enthusiast
Joined
Feb 11, 2017
Messages
4,196
Location
NorCal, Central Coast
@md17 ,, much clearer video.. unmistakable now, and apparently a short

Did you try running the same suspect duds 2x 18500 with a different module?

If you have the same issue, I'd dispose (dig a hole and bury) or find recyclers for the lithium
 
  • Like
Reactions: F89

desert.snake

Flashlight Enthusiast
Joined
May 8, 2017
Messages
2,064
Location
Eastern Europe
Feeling like there is a bad spring in the head. I had an HD Super, the head spring of which was not hardened and did not spring, it was flattened and there was unstable contact. You can put a round neodymium magnet between your batteries, after wrapping it on the sides with electrical tape or tape to increase the length of the batteries. Or the spring becomes soft when heated and contracts, losing contact.. I think need to remove and stretch the derailleur spring and add a neodymium magnet so that the head spring is fully compressed and cannot come loose and check again how the rear derailleur is screwed inside the button, could it come unscrew? No other thoughts yet
 
Last edited:

vicv

Flashlight Enthusiast
Joined
Mar 22, 2013
Messages
2,934
Location
Southern Ontario
Ya. Because, from what I can remember.(I know this is long post.) he tried primaries, and it worked fine. I've never seen protection circuits act like this, but that must be it
 

md17

Newly Enlightened
Joined
Oct 28, 2023
Messages
190
Location
usa ct
I received the new batteries. They work, but my last question before I'm totally done with this…is flickering when voltage is very low a normal thing with Malkoff lights? One measurement of 18500 cells when flickering started was 2.5 and 2.7 volts on each cell and I'd assume there'd be even more voltage sag when the cells get put under load.

or is it possible protection circuits cause flickering before shutting down completely?

Just to clarify, the flickering occurs with multiple lights same batteries
 

Attachments

  • IMG_5190.mov
    13.1 MB

thermal guy

Flashaholic
Joined
Jan 28, 2007
Messages
10,004
Location
ny
i Have many malkoffs and many 18500. When protection circuit kicks in the light shuts off. None of mine flickers on low voltage and I have done many runtime tests.
 

Lips

Flashlight Enthusiast
Joined
Mar 14, 2005
Messages
1,462
Location
Louisiana - USA
2.5 is too low


LI.jpg



LI2.jpg
 

vicv

Flashlight Enthusiast
Joined
Mar 22, 2013
Messages
2,934
Location
Southern Ontario
You're not really supposed to be using the protection circuit as your LVP. It's only there, just in case. I would say open circuit voltage should never be below 3.2 V. Which would work out to something like 2.5–2.8 underload
Malkoff lights (some exceptions) do not have low-voltage protection. So it should just keep gradually dimming no flickering.
It does not change when you are running cells in series. The discharge voltage is the same.
 

Lips

Flashlight Enthusiast
Joined
Mar 14, 2005
Messages
1,462
Location
Louisiana - USA
What he said...

Your just taking life off the cell by going so low. 3.3v they are essentially dead of power. Zebralight will flicker when Eneloop or Li Ion get to low.
 

vicv

Flashlight Enthusiast
Joined
Mar 22, 2013
Messages
2,934
Location
Southern Ontario
Yeah, if this is the way you normally treat your cells, it makes sense why they are dying. You would be lucky to get 50 cycles out of them with this treatment. If you're just doing it as an experiment but you normally look after them better, then it's no problem.
Now, if you are OK with knowing that, and that's just the way you want to use the cells, that's fine. But if I were you, I would definitely charge those outside under supervision. Deeply discharging them like that is what causes vent with flame when you charge them.
 

md17

Newly Enlightened
Joined
Oct 28, 2023
Messages
190
Location
usa ct
Yeah, if this is the way you normally treat your cells, it makes sense why they are dying. You would be lucky to get 50 cycles out of them with this treatment. If you're just doing it as an experiment but you normally look after them better, then it's no problem.
Now, if you are OK with knowing that, and that's just the way you want to use the cells, that's fine. But if I were you, I would definitely charge those outside under supervision. Deeply discharging them like that is what causes vent with flame when you charge them.
They're brand new and I do not do this normally, but what I am trying to determine at this point is if my lights are defective and flickering. They're all only a couple months old if that.
 
Top