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Question about multimeter and driver perfomance

jnrpop

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Re: Question about multimeter and driver perfomanc

When i measure the ma across the 1 ohm resistor, with my multimeter set to 2v setting it reads 0.050v
does this mean 50ma or 500ma??? this is with 9v in and a 100ohm resistor to substitute in for blu-ray diode.
 





Joined
Sep 20, 2008
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Re: Question about multimeter and driver perfomanc

jnrpop said:
When i measure the ma across the 1 ohm resistor, with my multimeter set to 2v setting it reads 0.050v
does this mean 50ma or 500ma??? this is with 9v in and a 100ohm resistor to substitute in for blu-ray diode.

That is a current of 50ma.... ;)
 
Joined
Nov 14, 2007
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Re: Question about multimeter and driver perfomanc

The only problem with using a 1-ohm resistor for current measurement is that the 1-ohm resistors are rarely 1 ohm! The ones that I've tried vary pretty wildly, with measurements of some being close to 1.2 - 1.3 ohms, which will screw up the one-to-one voltage to amp relationship.
 
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Dec 20, 2007
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Re: Question about multimeter and driver perfomanc

those 0.1-0.2 ohm is probably resistance of wires from multi metar.......put your multimetar to measure the resistance and shortcut the wires and you will see how much he lies in his measurements........mine lies 0.8-0.9 ohm.......that happened to me once when i bought 1.5 ohm resistor and when i test him with multimetar he showed 2.4 ohm.....later on i figured out that this is what it was about.............
I hope i helped you
 




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