How Do I Solve AC Nodal Analysis Equations on an HP 50g Calculator?

AI Thread Summary
To solve AC nodal analysis equations on the HP 50g calculator, users should enter the equations in matrix form rather than using the MSLV solver. The equations should be formatted with the voltage values in polar coordinates, ensuring to use the correct syntax for matrices. The user needs to input the constants on level 2 of the stack and the coefficients on level 1, then perform matrix division to find the solutions. It’s important to refer to the calculator manual for specific instructions on entering matrices. This method effectively resolves the simultaneous equations for unknowns V1 and V2.
trinidad2099
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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 into 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

V1(2.5∠-29.9)-V2(0.5∠0)=24∠0
V1(0.5∠0)-V2(0.539∠21.80)=4∠0

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(2.5∠-2.29)-Y(0.5∠0.)=(2.5∠-2.29)']
['X(0.5∠-2.29)-Y(0.539∠21.80)=(4.∠0.)']
{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.
 
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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.
 
Thanks! Didn't know that that was possible.
 
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