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AC nodal analysis with a HP 50g, help needed

  1. Mar 15, 2008 #1
    I've got a small issue at hand right now.

    I need to solve simultaneous equations with unknowns in order to do mesh and nodal analysis problems. The issue is, i can't figure out how to enter the equations in to get an answer out. My previous calculator was a t183+, so i'm not that well acquainted with the 50g or HP calculators in general.

    I read https://www.physicsforums.com/showthread.php?t=190871" thread, but can't seem to wrap my head around it.

    The set of equations i'm trying to solve is


    solving for V1 and V2.

    I'm using RPN mode as mentioned in another thread i found, and for the ∠ symbol i'm using the alpha+Rshift+6 insertion.

    So far i've tried entering the following without success.

    {X Y}

    I keep getting "invalid syntax" on the angle symbols when entering the equations, yet when entered as just (2.5∠-29.9) on the stack, they auto-convert to rectangular form.

    I've also tried with the rectangular equivelents like so.

    ['X(2.5,-0.099)-Y(0.5,0.)=(2.5,0.099)'] ENTER
    ['X(0.499∠-1.99)-Y(0.5,0.2)=(4.,0.)'] ENTER
    {X Y} ENTER

    That enters in properly and displays on the stack, but when i use Rshift+NUM.SLV MSLV i get "Bad Argument Type"

    Please let me know what i'm doing wrong, and feel free to ask for any other information or screenshots if needed.
    Last edited by a moderator: Apr 23, 2017
  2. jcsd
  3. Mar 16, 2008 #2

    The Electrician

    User Avatar
    Gold Member

    Don't use MSLV or other solvers to solve this type of problem; use the matrix arithmetic capability of the HP50.

    Put on level 2 of the stack:

    [[ 24 ]
    [ 4 ]]

    and on level 1(in polar and degrees mode); read the manual for info on how to enter matrices:

    [[ (2.5∠-29.9) (0.5∠180) ]
    [ (0.5∠0) (0.539∠-158.2) ]]

    Then press the divide key and see (in polar and degrees mode):

    [[ (10.089∠35.570) ]
    [ (5.448∠66.182) ]]

    or in rectangular and degrees mode:

    [[ (8.207,5.869) ]
    [ (2.200,4.984) ]]

    On the HP50 you won't see the double square brackets I've used here for a matrix; it will look more like standard matrix notation.
  4. Mar 16, 2008 #3
    Thanks! Didn't know that that was possible.
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