Hello Eric ,

Thank you for your reply. You mentioned -  " *You should read the voltage
across the resistor, not measure on both sides and take
the difference."  *I did not quite understand this line. Where exactly
should I place the resistor ,

Is something wrong with my arrangement - one side of the resistor on the +ve
terminal of the battery , the other side on the PCB ?
If yes - where do i exactly place my resistor ?

As far as the multimeter is concerned , I will try and get hold of a scope
by tomorrow.

Thanks ,

Somnath

> Yes, it's because you are using a multimeter.   With a 1 ohm resistor, you
> will be reading about .02 volts difference.   You should read the voltage
> across the resistor, not measure on both sides and take
> the difference.  Most multimeters do some autoscaling.
>
> You may have more success using the ammeter
> function if the only instrument you have is a multimeter.  We have one
> of the better
> Fluke hand held multimeters, and it measures the on current fairly
> well, but the current
> when the mote is sleeping is way off.
>
>
> Eric


On Thu, May 29, 2008 at 9:27 PM, Shomnat Mitra <[EMAIL PROTECTED]> wrote:
> Hello ,
>
> I have gone through several help archives to find a way to measure the
> current draw of the motes.
>
> All suggest using a 1 ohm resistor  in series with the + ve terminal of
the
> battery and the other end of the resistor attached to the PCB,
> and measuring the voltage across this resistor.
>
> The readings are 1.5V which is the battery voltage.
> I have tried several positions on the mote to attach the resistor, but
none
> show any change.
>
> The reading also doesn't show any change when I use HPLPowerManagement in
my
> programs.
>
> Is it because i am using a Multimeter ?
>
> Can anybody suggest the exact way to do this ?
>
> Thanks in advance ,
> Somnath
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