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MXDL 3W "AAA" Driver Question

ColdStl

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Hello,

I picked up 2 of these LED flashlights off of ebay with the intension of using them as hosts with flexdrives and PHR803Ts.
I wanted to test the included driver first, so I used a dead PHR803T and a 1ohm resistor as a test load.
I attached my dmm, set to Volts, and got a reading of 4.98 volts.
When I placed the dmm leads, set to mA, in series with the 1ohm resistor, I got a reading of 0.00 mA.
I placed the dmm leads back into the parallel position and got a reading of 96.4mA. I know this isn't how it's supposed to be done, so I'm wondering what I did wrong.
First...Will this driver work with a PHR diode?
Second... Can someone tell me why I can't get a mA reading?

Here is a pic of the driver...
 

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ColdStl

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Pic of the dmm reading..
I used the electrical tape so the wires would stay separate.
 

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daguin

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To measure mA you have to place the DMM in series with one of the lines to the diode

Peace,
dave
 

daguin

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If you have a resistor in line, you measure voltage across the resistor.  Someone up on Ohms law will have to help with what the "scale" should be.  If that is a 1ohm resistor then I believe the scale should be 1mV=1mA

Leave it hooked up the way you have it. Switch your DMM to voltage. It should measure mV.

If you cut the line, remove the resistor, and place the DMM in series (between the cut lines), then you can measure mA directly.

Peace,
dave
 

ColdStl

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Thank you! I'm gonna try again in a bit.
It would be cool if I didn't have to use a lavadrive for this build. If I can get a good reading I will let everyone know what it is. These flashlights are under $10 for two, shipping was free.
 




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