# \*EQUATION and node set

**URL:** <https://calculix.discourse.group/t/equation-and-node-set/3923>\
**Category:** Analysis issues\
**Created:** [April 22, 2026, 6:19am UTC](https://calculix.discourse.group/t/equation-and-node-set/3923 "2026-04-22T06:19:58Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![linth](https://avatars.discourse-cdn.com/v4/letter/l/898d66/32.png) [@linth](https://calculix.discourse.group/u/linth)\
**Post date:** [April 22, 2026, 6:19am UTC](https://calculix.discourse.group/t/equation-and-node-set/3923/1 "2026-04-22T06:19:58Z")

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Hi there,

I have problems setting up \*equations using node sets.

There is somewhat different documentation for different ccx versions on setting up equations using node sets but there is an example input file beamequset.inp and the according reference output beamequset.dat.ref, e.g. in \CalculiX\ccx\_2.23\test\ which contain the lines

\*NSET,NSET=LOAD  
±- 20 lines: 5,----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------  
\*EQUATION  
2  
LOAD,3,1.,100,3,-1.

Running with a precompiled 2.23 linux executable the example runs just fine. However, when I run the example beamequset.inp using ccx for Windows (as in PreProMax or from bConverged) and also on [FEA Cluster](https://www.feacluster.com/web_calculix.php) I got the following error:

\*ERROR reading \*EQUATION. Card image:  
LOAD,3,1.,100,3,-1.

STEP 1

\*ERROR in calinput: at least one fatal  
error message while reading the  
input deck: CalculiX stops.

Does anyone experience that problem and is there a simple fix other than not using node sets?

Thanks,

Thomas

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<div class="post-metadata">

**Author:** ![Calc\_em](https://avatars.discourse-cdn.com/v4/letter/c/43a26b/32.png) [@Calc\_em](https://calculix.discourse.group/u/Calc_em)\
**Post date:** [April 22, 2026, 6:51am UTC](https://calculix.discourse.group/t/equation-and-node-set/3923/2 "2026-04-22T06:51:49Z")

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Support for node sets in equation constraints was added in ccx 2.23. Any older version (such as likely the one on that website) won’t allow it.

See: [CalculiX: New features in Version 2.23 of CalculiX](https://www.dhondt.de/new_calc.htm)

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<div class="post-metadata">

**Author:** ![linth](https://avatars.discourse-cdn.com/v4/letter/l/898d66/32.png) [@linth](https://calculix.discourse.group/u/linth)\
**Post date:** [April 22, 2026, 7:37am UTC](https://calculix.discourse.group/t/equation-and-node-set/3923/3 "2026-04-22T07:37:50Z")

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Thanks for the hint, running with win executables from [https://www.dhondt.de/calculix\_2.23\_4win.zip](https://www.dhondt.de/calculix_2.23_4win.zip) does work