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I'm using ammeters as simulated light bulbs for learning basic circuit design and it helps to have voltmeters at various locations. The voltmeter resistance is allowing extremely small currents to show on the ammeters when I would like to show a zero value.

You cannot set a resistor in CL to infinite resistance. Therefore you cannot set a voltmeter to have infinite resistance.

You can set the CL voltmeter resistance to an arbitrarily high value but values above about 1T (1e12) may cause simulation problems.

You could put a VCVS across in place of the voltmeter and either read the voltage at the output directly or measure that with the voltmeter.

That works because a VCVS does have infinite input resistance.

However ...

Real Voltmeters do not have infinite input resistances and it might be as well for your students to understand that sooner rather than later because that is what they will see in the real world.

If you want zero leakage currents then don't confuse them by using a voltmeter. If you want to demonstrate ideal voltage measurements then use an ideal voltage measuring device - the VCVS - to measure it.

:)

Appreciate the detailed response and reinforcing that we must consider the effects of measurement (quantum mechanics students take note.)

@dnharris,

May Heisenberg smile down on you!

:)

You could run the DC simulation, then subtract voltage from one wire to another. Alternatively, if you want to figure out the Vdrop for a certain component, you could add the expression P(Name)/I(Name.nA) where Name is the the name of the component.