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Hi,

What does this error mean: "Error creating Bode Solver non-finite scale"? I've created a circuit with a parallel R (2.2k) L (46m) C (22n) circuit with a sine-wave voltage source; nothing spectacular.

The DC solver thinks everything is OK, but when I try to run a frequency sweep from 10Hz to 10e6 Hz, I get this Bode Solver error.

When I put the RLC elements in series, it works just fine.

Anybody can point me in the right direction? Thanks in advance!

If you'd like to post a link - which can be to an unlisted rather than public circuit - then people may be able to offer help more easily.

Ah, I didn't realize the difference. So, here it is:

Um,

No it isn't ...

Ahum, I'm sorry. It should be visible now?

The error message is really not very helpful is it?

It is trying to tell you that you have an ideal voltage source shorted out by an ideal inductor. If you put some ESR in the inductor then the error message goes away and the circuit simulates.

However, the V(out) plot shows silly numbers because you can't attenuate the output of a pure zero impedance voltage source by putting a finite impedance across it.

The signal source needs to have a finite source impedance.

You need to either add some series resistance between the V sine source and the rest of the circuit or replace the V source with an I source with a source resistance in parallel with it.

Two things:

1. This case and some others seems to suggest that a non-zero default ESR for inductors would be helpful to many users.
2. @olafz, you may wish to try plotting the current (for example "I(V1.nA)") since you're looking for an impedance local maximum at resonance. Alternatively, you can use a current source to drive into your parallel RLC system, and then plot the voltage.

Thanks everybody!

@mrobbins,

1) Good plan.

I thought I'd raise a bug report for inductor ESR but I can't find one from me.

The suggestion of non-zero inductor resistance did come up in:

https://www.circuitlab.com/forums/support/topic/qgs9898s/bug-report-series-switches/#comment_1483

and

https://www.circuitlab.com/forums/support/topic/zruexp65/beware-inductors-in-cl-do-not-properly-conserve-flux-if/#comment_1962