Connect with us

problem with AC analysis in SwCadIII

Discussion in 'Electronic Design' started by Geert, Aug 19, 2006.

Scroll to continue with content
  1. Geert

    Geert Guest

    Hello,

    I wanted to analyse (AC) an R L C chain (serie) with one voltage
    source.
    The result were good when measured between an node and ground.
    Does anyone know how to measure between nodes?
    Is a common grond really necessary in this case?
     
  2. Genome

    Genome Guest

    Right click on the circuit. At the bottom of the pop up menu there is an
    item 'set probe reference' click that and click on a node in the circuit to
    set your new reference point.
     
  3. Or. Left-click on the first node, hold the button down,
    drag the mouse to the second node, release the button.
     
  4. There is a mailgroup devoted to SwCAD, and it's better to ask there. But
    when you click on 'Run' and the panel asks you to choose what to output,
    double-click and enter Vn(00x)-Vn(00y), with your node references for x
    and y.
     
  5. Hello Tony,

    How to do this with cursor and mouse has been already answered
    by the others.

    You can also enter a difference directly in the "Add Trace"
    dialog. Just enter the following (replace netname1,2 with
    your nodenames).

    V(netname1,netname2)

    You could also enter this in the long form, but the previous
    method is more elegant and shorter.
    V(netname2)-V(netname2)


    You always need at least one GND in your circuit in every SPICE.

    A DC-path to GND is necessary from every node.
    This is important if you simulate isolated circuits.
    You have to add then a resistor to GND at one point
    in the isolated section, e.g. 1000GOhm.
    Best regards,
    Helmut
     
  6. Sorry Tony,

    I should have written Geert.

    Best regards,
    Helmut
     
  7. New glasses (asap) Helmut, please. :)
    There is one other method, very useful when the plots
    have to be shown to others, so a less cryptic syntax is
    desirable.

    Put a x1 VCVS across the two nodes, -output to earth
    and +output appropriately labelled. In this case the
    OP could (say) have an output labelled "L1". The plot
    would then display V[L1]. This is nicely consistent
    with LTspice's labelling of currents, eg I[L1].
     
  8. Geert

    Geert Guest

    Helmut Sennewald schreef:
    Thanks Helmut,

    My problem is solved.

    Best regards
    Geert
     
Ask a Question
Want to reply to this thread or ask your own question?
You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.
Electronics Point Logo
Continue to site
Quote of the day

-