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Not sure what thread you'd be referring to since that was ages ago - but usually people round here measure current with a shunt and a voltmeter. Something like a big wirewound 1ohm resistor makes it easy, so 1A=1VCyparagon
What did you used to measure the current on your 2013 post ?
He posted this , but i want to know how he got this , i know that its an oscilloscope but its a current clamp plugged in or else ?Startup spikes are downright terrifying. And it would probably be worse (to the point of blowing up my test load perhaps??) If the voltage set point was higher. As always, note the time base in each image because they change to show detail.
At 1.8A switched before the driver:
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Not sure what thread you'd be referring to since that was ages ago - but usually people round here measure current with a shunt and a voltmeter. Something like a big wirewound 1ohm resistor makes it easy, so 1A=1V
I have some 1% 1 ohm resistors in power ratings from 5 watts up to 100 watts. It is important to get the most accurate resistors you can to measure current using a shunt resistor. It is easier to incorporate either a 1 ohm or a 0.1 ohm resistor in a dummy load to measure the current as you don't have to interrupt your circuit to put an ammeter in series with it. Also, you needn't worry about blowing a fuse in your ammeter if you select the lower range than the current passing through your circuit.
I have found a 3w 0.1ohm 1% resistor .Yes, you should be able to see noise on your line if it exists, but you won't have an accurate measure of your current. In order to get that you need large, short connections between components in your dummy load and the most accurate resistors you can find.
Should do nicely - Specially made shunts work even better - but that'll be perfectly accurate to see what you need here. There are extremely high-precision high-current shunts avaliable but it's total overkill for a laser.I have found a 3w 0.1ohm 1% resistor .
Resistor way (used a potentiometer set to 1ohm)
It is important to get the most accurate resistors you can to measure current using a shunt resistor.
In order to get [accuracy] you need large, short connections between components in your dummy load
for currents exceeding 4 amps where small, long conduction paths can add resistance and inductance to your circuit.
Cyparagon
What did you used to measure the current on your 2013 post ?
Hey , i just want to check the input current for a brief moment , i dont need a ultra precise measurement. Just on/off for 2 s.