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ArcticMyst Security by Avery

Build almost done!! 1 fast question.

Joined
Oct 5, 2012
Messages
99
Points
8
Well. I never tried to measure resistance lol.
Am just curious how much current will go to the diode.

Note.. i did not build the negative side of driver yet.. :p

if you want to measure your current then you need a test load.

EDIT- you can use just a multimeter for this driver too(no test loads needed for linears), but you have to have your multimeter set at C, and have the negative side hooked up (multimeter wont go above 1ma unless you have negative side hooked up too :D)

maybe look up how to use a multimeter... it seems that you might not fully understand, ohms law also, that helps get your resistors needed by plugging in your target current in equation (R=V/I) (I=current)
 
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tony1

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Joined
Jan 4, 2012
Messages
54
Points
0
You can buy a dummy test load.. These dummy test loads comes in various input Current. If you use a low one it may blow. Use a higher capacity. Don't use a multimeter. Buy an ammeter, connect it in series to the load. If you know the total value of the resistor and the voltage supply , you use Ohm's law to calculate the Current. You can goggle for constant current calculator and a table with various resistors and the current output. Good luck.
 
Joined
Oct 5, 2012
Messages
99
Points
8
You can buy a dummy test load.. These dummy test loads comes in various input Current. If you use a low one it may blow. Use a higher capacity. Don't use a multimeter. Buy an ammeter, connect it in series to the load. If you know the total value of the resistor and the voltage supply , you use Ohm's law to calculate the Current. You can goggle for constant current calculator and a table with various resistors and the current output. Good luck.

you actually can use a multimeter for linear drivers :) but a dummy/test load is always good. you will have other builds that wont use linears at some point.

with x2 5 ohm resistors you will get 500ma which is a bit high. x3 10ohms resistors would work. i guess you have a pot so x2 5 ohm could work...
about the multimeter w/ linears if a vet or pretty expirenced could correct me if im wrong.(or say im right :))
:beer: Justin
and again you can look up lm317 calculator for current if needed
 
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tony1

0
Joined
Jan 4, 2012
Messages
54
Points
0
You can use a multimeter to measure the current. But if you use an ammeter to measure the current , you have a multimeter handy to measure other thing around the circuit.

Get the table at REUK.CO.UK. LM Current Calcultor
 




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