Measure current and voltage using DMM sharing one port

[livermor]

I want to measure the voltage at several points on a pcb, where I connect the DMMs ports to the pcb using simple plugs. The switching between the different voltages is done using muxes. So the black port of the DMM (the second from top in picture) is connected to ground to give correct volt measurement.

And then I want to measure current through different lines. The problem arises here. Since the two measurement types share a port, how to get the correct current and voltage measurement? The second port from top would be connected to ground, so I can't use the method of measuring the voltage across the line through a resistor with known value, since then the second port should not be connected to ground. How can I use the current measurement state of the DMM? How does it measure current? Are there any practical examples of this? Tried looking through the manuals, but couldn't find any good starting points.

 

[Omar_II · Accepted solution]

so I can't use the method of measuring the voltage across the line through a resistor with known value, since then the second port should not be connected to ground.

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On all of my test sets I have to mux my ground signal along with the hi side of my signals.

All my test sets mux are set up for 2-wire topology because there is no other way to do it without switching the low side also.