Malkoff legos

kerneldrop

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Thanks for the info, any chance to see the setup in action?
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thermal guy

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Ya I’m not sure but 2.6 or so is what you should be getting with 2 primary 123’s. I wish it wasn’t but….
 

kerneldrop

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The LED is an XP-L High Density, a 3 volt LED

The driver malkoff uses is a buck driver that only pumps up to 3v to the LED. This allows multiple batteries to be used.

so at 3 volts pushed to the LED by the driver, the LED is pulling ~2.5amps without any help from the driver, which is 7.5 watts
1657294053404.png


at 2.5 amps, the LED is outputting around 200% of it's lumens when at 1amp. 200% is around 920 lumens.
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When at 1 amp the LED is putting out around ~460 lumens
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All that is what's happening on the LED side of the driver.

Here is what's happening on the battery side of the driver:

Malkoff's top secret driver at 9 volts is pulling 1.4 amps, which is 12.6 watts.
Amps = Watts / Volts

So, 12.6 watts from 6 volts = 2.1 amps that only increases during use. So like Thermal said, 2.5 is around where you should be with steady use from a 6v setup.

the LED only needs 3v @ 3 amps (9 watts) to reach the 1,000 lumens that Malkoff advertises (per the graph above).
so that shows you how much "power" is lost between the batteries and the LED.
 

kerneldrop

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I tested my M91.

These are at turn-on readings:
~2.50 amps at 6.5 volts
~2.67 amps at 5.7 volts

I drained two new battery station CR123 almost 1 volt in 10 seconds.
 

fulee9999

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now I got curious, so I unpacked three brand new CR123s, to see what's what, here are my results with my M91BN:
1xCR123 - 3.23V - 0.24A
2xCR123 - 6.47V - 1.48A
3xCR123 - 9.71V - 2.52A
 

Mr. LED

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Yesterday, using my new M91BN and MD2 body, on a fully charged 18650 GA unprotected, 6 minutes drew exactly 240mA from the battery. Should I assume exactly 10 times more for a full hour, is it that simple and linear?
 

kerneldrop

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now I got curious, so I unpacked three brand new CR123s, to see what's what, here are my results with my M91BN:
1xCR123 - 3.23V - 0.24A
2xCR123 - 6.47V - 1.48A
3xCR123 - 9.71V - 2.52A

Oh wow, your 9v would be 24.5 watts. That would put 8 amps going to the LED.
I'll test mine at 9v later tonight.

My assumption was that your 9.71v readings would be lower than Malkoff's since your 6v readings are lower.
Do you have readings from any Malkoff lights that agree with Gene's numbers?

The only light I've been significantly off on is his MDC AA 3 mode. I'm no where close.... so you being off is certainly possible.

Is there a significant brightness difference in the 6v vs 9v?


Yesterday, using my new M91BN and MD2 body, on a fully charged 18650 GA unprotected, 6 minutes drew exactly 240mA from the battery. Should I assume exactly 10 times more for a full hour, is it that simple and linear?

Yes, for just conversational ballpark accuracy....BUT -- as volts decrease the mA increase. The volts will decrease under load and from usage. That is why @thermal guy does runtime tests the old fashion way by sending lumens until it doesn't.
Assuming an unprotected battery, eventually there won't be enough volts to power on the driver.
 

fulee9999

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Do you have readings from any Malkoff lights that agree with Gene's numbers?

The M61N according to Gene draws 0.8 amps at 6V, I measured 0.91A at 5.26V. So that would put it 4.8 watts officially, and 4.78 watts what I measured. I'd say that's well within measuring error margin, so pretty much perfectly the same.

Is there a significant brightness difference in the 6v vs 9v?

No, not really. To my eyes they are both pretty damn bright.
 

thermal guy

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now I got curious, so I unpacked three brand new CR123s, to see what's what, here are my results with my M91BN:
1xCR123 - 3.23V - 0.24A
2xCR123 - 6.47V - 1.48A
3xCR123 - 9.71V - 2.52A
Interesting. Your draw reading for 2X123 and 3X123 are basically the exact opposite of what I’m getting. 2X123 I’m getting 2.5A 3X123 I’m getting 1.5A. Your volts seem high. Are you testing them in your light or just sitting out? 2X123 should be 5.8-5.9 volts and 3X123 should be around 8.5.
 

fulee9999

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Interesting. Your draw reading for 2X123 and 3X123 are basically the exact opposite of what I’m getting. 2X123 I’m getting 2.5A 3X123 I’m getting 1.5A. Your volts seem high. Are you testing them in your light or just sitting out? 2X123 should be 5.8-5.9 volts and 3X123 should be around 8.5.

Actually I'd like to revise the voltages, I forgot that I noted down only the unloaded voltages, so voltages under load, and amps:
1xCR123 - 2.19V - 0.18A
2xCR123 - 4.43V - 1.40A
3xCR123 - 7.26V - 2.53A

So yes, the voltages are now the proper in-use voltages, but the amps are roughly the same.
 

:)>

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No love for the MDC unshrouded bidy with the Surefire Tactician head? This combo is incredible…
 

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