How do I measure m43 amperage?

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trailhunter
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How do I measure m43 amperage?

I see 4 screws exposed once I remove the tail cap, can I safely test from screw to body?

DB Custom
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Nope, that won’t do it. Those screws in the tail cap hold the negative end PCB down and help achieve ground.

The best way I know is to use a clamp meter from the top, after removing the bezel and lens and the cover board then also removing the 4 triple optics, this requires de-soldering the negative lead at the MCPCB and soldering in a loop of wire sufficient to get the clamp meter around it. This will tell you how many amps the LED’s are actually pulling. Remove the loop and solder the black lead back down, replace the optics and the cover board then reassemble the bezel.

The leds aren’t set up in 3V configuration so you may want to measure on voltage at the MCPCB at some point, to know just what those amps are actually doing wattage wise. (VxA=W)

trailhunter
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DB Custom wrote:
Nope, that won’t do it. Those screws in the tail cap hold the negative end PCB down and help achieve ground.

The best way I know is to use a clamp meter from the top, after removing the bezel and lens and the cover board then also removing the 4 triple optics, this requires de-soldering the negative lead at the MCPCB and soldering in a loop of wire sufficient to get the clamp meter around it. This will tell you how many amps the LED’s are actually pulling. Remove the loop and solder the black lead back down, replace the optics and the cover board then reassemble the bezel.

Thanks!

DB Custom
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You may also want to measure Voltage in the on state while you have it apart, the emitters are not configured in 3V arrangement so it will help to know the actual working Voltage so you can figure what the amp reading means. Remember, VxA=W. Wink

trailhunter
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DB Custom wrote:
You may also want to measure Voltage in the on state while you have it apart, the emitters are not configured in 3V arrangement so it will help to know the actual working Voltage so you can figure what the amp reading means. Remember, VxA=W. Wink

Thanks dale’s, I actually put up a separate thread to help me troubleshoot testing the mcpcb. I’m testing all emitters on the mcpcb at 4.10v but none of them turn on. Do I need to test mcpcb at 12v? Each emitter individually lights up when testing each one.

DB Custom
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Each triple board is wired in series, two of the 4 are wired together and the other 2 remaining are wired together, so it probably works at around 11V. (Technically 12V)

DB Custom
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I rewired mine to all work in parallel, built an FET driver for it, with slaves, and run Anduril. It’s very powerful but of course it gets stupid hot very fast, hot enough to glitch the driver as it tries to deal with the heat. I can only run it about 15 seconds and then if I don’t turn it off it will lock up, in the on position… have to remove the tube to kill it. It’s making some 12,000 lumens though, if I recall correctly.

DB Custom
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With it assembled but naked (optics removed) turn it on to the highest level and read Voltage across the two wires, that will tell you exactly what it’s running at in the Voltage department.

trailhunter
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DB Custom wrote:
Each triple board is wired in series, two of the 4 are wired together and the other 2 remaining are wired together, so it probably works at around 11V. (Technically 12V)

Ah ha! That’s the reason then. Ok tested at 11V and it almost knocked the socks off. I tested at 6.9v just enough to see visible light coming out of each emitter and it’s good, thanks for helping! Thought I blew an mcpcb

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Ultra compact powerhouse, they are. Took me a while to figure out the four triples namesake, 43, but I finally “saw the light”. LOL