Q8, PMS SEND TO THOSE WITH ISSUES BLF soda can light

I think the most amps the Q8 will pull with the best cells is about 16 amps. So that’s 4 amps per cell.

The protection circuitry adds some resistance so maybe you will see 14 amps? That’s 3.5A per cell. That should be no problem for those cells.

Oh thank you. I do not think these are crucial features I would need.

What??? Of course you need them. Everyone needs them.

Just curious, how does protection circuitry work?

For instance, I have the LiitoKala Panasonic NCR18650B protected 18650s, whose protection I have tested to trip at around 6A (tested in Astrolux S41S).

I tested using the same single protected Panasonic NCR18650B (only 1 battery) on the BLF Q8, and it does trip when I ramp up the brightness (trips not yet reaching max brightness). Then I tested just inserting 2pcs protected Panasonic NCR18650B in the BLF Q8 — I could turn on the BLF Q8 in Turbo mode and the protection circuit does not trip at all.

Since 1 protected battery trips at 6A, does that mean if 2 batteries used, they would trip at around 12A? Now since the BLF Q8 did not trip when using 2 protected NCR18650Bs at the same time, would that imply the BLF Q8 uses less than 12A at Turbo?

The protection circuitry in batteries do many things.

It protects against:

Over voltage (while charging)
Over discharge (when using)
Over temperature (sometimes)
Over current (limiting amps)
Short circuit

No. There are other factors at play. When you use only 2 of the protected cells you get higher voltage sag. 2 cells will droop down to a lower voltage under load, compared to 3 or 4 cells which limits the amp draw. Higher voltage equals higher amps. Remember Ohms law.

It would not surprise me to see 2 protected cells in the Q8 only draw 10 to 12 amps.

Battery chemistry also comes into play. The Panasonic B & GA cells at 3400mah and 3500mah are designed to give longer runtimes at the expense of max current output.

Then you add the extra resistance of the protection circuitry added to the cell and you just don’t get as many lumens.

It’s still plenty bright, but 4 high drain, unprotected cells will give you the max current and max lumens.

I kind of lost my train of thought here so hopefully I answered your question.

I just put cells back into my Q8 from the first batch, after not using it for a long time, and found that the switch light is no longer working. This is not really a major crisis, but is there a replacement available?

Is there any posibility that is just got disabled?

Yes, see this post.

I have a quick question. When I turn this Q8 on in moonlight, via long press from off, and then set it down still on my desk, it stays in moonlight from between 30 and 45 seconds, and then switches to turbo on it’s own. Sometimes, long press from off to attempt to enter moonlight will go to full turbo, too.

I timed the switch from moonlight to turbo with a stopwatch over and over, and it is consistently between 30 and 45 seconds.

Is this normal?

Settings are:
ramping - on
blinky modes - off
moonlight level - 2 (also repeated results in 3,4, etc)

There was a bug involving moonlight switching itself to turbo, but I thought that was fixed quite a while ago. IIRC it was something about moon being a separate mode with an index way above the top of the ramp, so if it tried to step “down” it would end up really bright. Does it continue to step down after that, if you leave it on? Are the batteries low, or perhaps does it think it’s overheating?

so far my Q8 is working flawlessly. I use it quite a bit and continue to be impressed by it every time i ramp it up :+1:
Worth every penny and even if ive said it before, thanks once again to everyone, awesome job!

I was worried mine would do the same thing as I received one of the first lights. Tried it and all is well thankfully. Sorry about yours.

Thank you for the reply, ToyKeeper. Here are the results:

Yes, apparently it does, about 30 seconds after turbo is unintentionally activated, it steps down again, also on it’s own.

Thanks for the idea. I’ve just now ruled this out with some fresh, fully recharged ones, so no. I used fairly new genuine Samsung 25r batteries for this test.

Results:
Disabling the thermal (setting 3, option 1) appears to make it go away. How interesting!
Setting thermal to “timed” (option 1, 60 seconds) also makes it go away.
After “re-calibrating” the temperature based to something so hot I can barely hold it and then allowing it to cool, the bug comes back.

The light shows 1 blink for firmware, which could mean version 1 or 1.1. Who knows. Did you guys install a way to flash this firmware?

I hope this helps narrow down the issue.

Okay, so it is the thermal step-down triggering when it shouldn’t. I don’t recall if that was one of the things Tom fixed in v1.2, but the Q8 is relatively easy to reflash if you want to try it. Remove two screws and the driver should pop out far enough to access the relevant parts.

More information on reflashing is in the firmware repository linked in my signature, in the “README” file.

Or, the timed step-down is probably good enough… no thermal measurements needed.

… and firmware is kind of a rabbit hole. Definitely try it if you’re interested, but be warned that it could turn into a new hobby. :slight_smile:

Thanks for the information. Yep, sure enough. The leads on the driver are plenty long enough. I must say that these solder joints are really smooth and pretty, too, with all residue removed. They’re really well done. Wow! I’ve seen some nasty, scary looking PCBs from China, but this one is fantastic.

I’m sure that in the next few weeks I won’t be able to help myself, although, as you suggested, it truly is a tiny problem.
I do need to thank you for all of your help. Without your help, I wouldn’t have been able to pinpoint it.

Thanks again.

@Longtom
The Firmware is v1.0
v1.1 was only for the BLF GT prototype.

This is an old bug fixed in NarsilM v1.2. The v1.2 HEX file and a v1.3 BETA hex file are posted on my google drive share, but of course this won't help those that can't download . Sorry bout this.

Here's the latest ReleaseNotes.txt file:

For Vers 1.3 2017-10-16:
tweaks made to battery voltage level readings:
- The single cell mode using the internal V ref and no resistors appears to be more accurate now, rounded to the blinked out value.
- for using R1/R2, it should also be more accurate now - still in testing


For Vers 1.2 2017-10-16:

ADDED : (from MAD777, maybe others) if strobes are disabled, a 2X click from 2X turbo should restore the previous level you were at
FIXED: 4X clicks in modes operation engages lockout - not supposed to
ADDED: operation change: make click&hold in MODES or STROBES wrap from 1st mode to last
FIXED: in LVP switch LED control: the LED sometimes is left on after an LVP drop, and is not blinking the way it should be. The "bug" is that I'm trying to control the switch LEDs from multiple places so it's getting turned off quickly after turned on, and left on when it should be left off. It's a timing thing, so has sort of a random pattern - sometimes left on, sometimes left off. The 8 sec LVP blink need to be qualified better, and should not be calling Setlevel() as is because it wants to control the LED
FIXED: temp stepdown should not happen right away from turn ON. Delay it by 15 seconds
FIXED: for temperature stepdown, in moon mode, a temp stepdown is actually done because moon mode is marked as special level 255, which is considered as a high level of output instead of very low. The stepdown results in the light switching much brighter. This should only happen id the temperature threshold is set to a low temp, or the light is still hot and not cooled down when moon mode is chosen. It can also result in an immediate jump to the stepdown level as soon as the light is turned on in moon mode. Might appear as a bright flash when ramping first starts.

There's more previously implemented:
- added momentary/tactical mode via 5X clicks in ramping mode - only active til a power reset (full turbo only when switch is held down) - It's only accessible from ramping mode, not Mode Set operation
- full BLF GT buck driver support
- capability of setting max ramping to less than full max FET (Hi mode), while the 2X click still goes to full FET turbo. This is being used for the GT buck driver configuration.
- added more compile switches, little better custom configuration of the source in header files

Teacher and Jason, thanks. I will check it out after work tonight.

TomE would you please check your PMs. It’s been over 11 weeks since your last response indicating you were finished modifying my q8. Thanks in advance.