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bailey · 10-30-2005, 10:03 PM

ok, lets try this.
the power supply has several sources12volts, 5 volts + 5 volts - , 3.3 volts. and so on, each one is able to deliver x amount of amps as stated on the lable. the total of all the sources will be the total that the supply can deliver.
and still be within the rated plus and minus rateing of the regulator.
each source is able to deliver the amount of power that is stated on the lable.

if you want to measure each load from the power supply one at a time, then you must place a amp meter in series with each one of the supply wires, true a MM will not be able to do this so you must use a bench meter that can do this or place a shunt across the meter and that will give the results your looking for, any electronics book can show you how to pick the proper shunt for your meter, itd the same standard ohms law use.
a good source for a 12 volt dc load would be to use some 100 watt 12dc lamps connected in parrlal to provide the desired load, then just measure the ampe or add up the 100 watt bulbs.

10-30-2005, 10:03 PM	#18
bailey Member (14 bit) Join Date: Mar 1999 Location: Christmas, Florida Posts: 10,661	ok, lets try this. the power supply has several sources12volts, 5 volts + 5 volts - , 3.3 volts. and so on, each one is able to deliver x amount of amps as stated on the lable. the total of all the sources will be the total that the supply can deliver. and still be within the rated plus and minus rateing of the regulator. each source is able to deliver the amount of power that is stated on the lable. if you want to measure each load from the power supply one at a time, then you must place a amp meter in series with each one of the supply wires, true a MM will not be able to do this so you must use a bench meter that can do this or place a shunt across the meter and that will give the results your looking for, any electronics book can show you how to pick the proper shunt for your meter, itd the same standard ohms law use. a good source for a 12 volt dc load would be to use some 100 watt 12dc lamps connected in parrlal to provide the desired load, then just measure the ampe or add up the 100 watt bulbs. Last edited by bailey; 10-30-2005 at 10:08 PM.