Measuring flashlight current (pic included)

[reneki]

I can't seem to get an amp reading, I've got the multi in series and set to 20A. Maybe the wires are no good? I do get voltage readings when testing battery though.

It's a DD flashlight, with a P4 led and 18650 battery. (x2000, dx flood to zoom)

 

[xenonk]

It's a circuit; the electricity needs a return path.

You need something connecting the outer ring of the driver to the battery tube.

 

[Chodes]

This should work better.

edit: assuming that is your tailcap on the right in your pic?

 

[reneki]

It's a circuit; the electricity needs a return path.

You need something connecting the outer ring of the driver to the battery tube.

well when you put it that way, i see how it's not really a circuit when it's not all connected. I tried using the case instead and it works, got a 700ma reading.

 

[Bones]

Welcome to CPF reneki.

If you're interested in testing other components of your flashlight, HKJ has authored a most useful guide for using your DMM for measurement:

http://www.candlepowerforums.com ... post3015928

For future reference, it's linked in the threads of interest in the first post in this sub-forum.

 

[reneki]

Welcome to CPF reneki.

If you're interested in testing other components of your flashlight, HKJ has authored a most useful guide for using your DMM for measurement:

http://www.candlepowerforums.com ... post3015928

For future reference, it's linked in the threads of interest in the first post in this sub-forum.

thanks, that's a very informative thread.

 

[DonShock]

FYI: Another thing to remember when troubleshooting a "0.00" current indication is that the Amp jacks on most multimeters are fuse protected so if you accidentally short something you can blow the fuse. If this happens, the meter will be an open spot in the circuit and no current will flow giving you the zero reading.