Aboutcleggsan Expertise All technical areas of Electronics Engineering.
Experience BSEE, MBA, Design, R&D, University Research.
Senior Life Member of IEEE. Life Fellow of AES.
Organizations IEEE, Consumer Electronics Society, Audio Engineering Society.
Broad teaching experience; work experience mostly in consumer electronics and conversion from analog to digital technologies. Pioneer in digital audio at all levels.
Question If I have a series circuit with a DC source and say 4 resistors of varies ohms and I want to test for voltages at different points in this circuit say if point A was at the top left hand corner with 1 resistor between it and the source and then I want to check the voltage at point B with a resistor between point A and point B and so on how would I hook up my meter to get the correct readings.
Answer Most circuits; that is, for the sake of uniformity, are drawn to have a common or ground line at the bottom of the view; then all voltages are taken with reference to that. In other words, the ground or black lead of the volt meter is connected to the common/ground line and the red probe is connected to the various nodes of the circuit.
That being said, in some cases, for sake of education and investigation, sometimes the voltage may be taken directly across the component in question - but only for battery driven voltmeters which do not have a chassis ground problem.
If you have a simple resistive network, with all of them in series, you can either connect the voltmeter across each one of the resistors and add up the voltages, or you could connect the gnd lead of the volt meter to the negative side of the battery supply and take the voltages across each resistor and show how it drops from the max to the various points in between.
Does that help? Let me know if you need further explanations. This is Kirchoff's law of series voltage drops; the sum of the drops across the resistive elements must equal the battery emf potential.
