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I am setting up an example for my students in my scientific computing course, and have a basic question about sign conventions.

I have a single loop below:

My question is, what sign convention is being used here? It seems as if flow from negative to positive is the positive flow direction. Or is my ammeter just upside down?

Any help would be greatly appreciated!

@donna,

Welcome to CL.

CL indicates "conventional" current flow from positive to negative (this is the same as in spice).

So your ammeter indicates negative current (i.e. it is upside down).

Note that the indicated current through all components in spice and in CL depends on the orientation of the component.

Try plotting the current through R4.

Note the the polarity of the current.

Then cut R4, paste it back onto the page, do "H" to flip it horizontally then, if necessary, move it back into the circuit.

Run the sim again and note the polarity of the current.

That can lead to confusion if you forget to keep track of pin (node) numbers on devices!

:)

Thank you for your help. The class went great, even if half the students (mostly engineering students) knew more about circuit diagrams than I do. I am in a math department.