Please Help With a Little Info

[Knifefeak]

I have a couple v54 lights (which are awesome) but i have always been curious about how much amp draw they are pulling off the batteries. I want to know this so if i take them camping or use them for emergency situations I know how long a set of batteries will last. I asked Vihn and he never did a test other than how many amps with the lights on high.

These are the lights that I have

tn31vn
mvnVostro
k40vn

I have a good digital Multimeter so if you don't have this info and know how to measure this i would be equally grateful.
Knifefeak

 

[Norm]

Simple-guide-to-using-a-DMM-for-measurements

Norm

 

[Knifefeak]

are you saying just to run and time it

 

[Knifefeak]

Simple-guide-to-using-a-DMM-for-measurements

Norm

I tried taking off the tail cap and putting one lead on the centre of the battery carrier and the other on the inside of the flashlight body, my meter will measure up to 200amps. but nothing

it is also the clamp type, is using the wire inside the clamp a better method

 

[Norm]

You need to check your connections and meter settings. The linked instructions are correct. You don't need a clamp meter.

Norm

 

[Norm]

are you saying just to run and time it

Whats the formula to calculate a rough estimate of run time?

Norm

 

[Knifefeak]

I think I must have the wrong type of multimeter or something, because it doesn't matter how I try I get no reading

 

[Norm]

Do you have your meter leads in the correct sockets?

Norm

 

[Knifefeak]

Ya,red in red socket and black in black socket

 

[Norm]

Ya,red in red socket and black in black socket

There's often a separate socket for higher current.
From the first link.

 

[Knifefeak]

upon a little more research, my meter doesn't measure DC current so i don't think it is sensitive enough to read when the leads are on the right spots. i bought it today just for this purpose,ill try to exchange it for a proper one. Because it should be giving me a reading. Ill keep you posted
thank you

 

[chops728]

Better be careful--all your listed lights have 3 cells--the only way I've found to test them is --put the battery carrier in the tube with the switch plate screwed on the tube--therefore the light is separated at the head--- then you have to clamp red meter lead to head ground plate-- connect black lead to the tube edge (you can see where the edge is bare no anno and when screwed to the head it will contact the plate your red lead is touching--then you have to use a wire to connect center of battery carrier to the center spring on the head--confused yet plus you have to grow a third arm--- pretty simple once you grasp how the power flows from one point to the other--- once you know your amperage draw you can use this calculator to figure runtime
http://www.powerstream.com/battery-run-time-calculator.htm