Welcome to the TRNSYS Users Forum.
The forum is a place where people can interact and have discussions about different topics involving the use of the TRNSYS software package. Here you can post topics for discussion or questions on using TRNSYS and get advice from other users or TRNSYS experts. This forum is not intended for detailed technical support. Users should contact their distributor’s hotline for such assistance.
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Last seen: Jul 11, 2025
@danalee Dana, there are two ways that TRACE can be used. The simple way is to select the component whose inputs outputs, and parameters you want t...
@alish this is one of the stranger errors I have run into. My colleagues and I have run the project on a few different computers using exactly the ve...
@danalee The error would suggest that TRNSYS is sending a set of inputs to your *.m code that Matlab cannot solve. You might try adding a TRACE to you...
@alish Ali, it was probably me who suggested that over at techsupport! I'm sorry it didn't solve the problem. Are you just dragging out a Type33 (c or...
@soufiane_ze I am not aware of any freely available components. The TESS component is available at
@soufiane_ze warnings are designed to alert you to a potential problem in your simulation. If there are only a few then they can generally be ignored....
@soufiane_ze if you would like some more information about the commercially available TESS component that I mentioned in an earlier post, you can cont...
@soufiane_ze I don't think it is possible to model a VRF system with the components that are available in the standard library. You will need to get a...
@soufiane_ze It is not really possible to diagnose the cause of the problem from the screen captures. However, if I had to make a guess based on the...
@lisa there are a few models of PV/T in the TESS Electrical library. If you're modeling the building using Type56 you can look at Type563. If you're ...
@ashna Your equation uses some syntax that TRNSYS doesn't recognize. The "greater than" function syntax takes two arguments, returns a 1 if the first ...
@alirezakooshesh The heat pump model computes the required power consumption. That value would have to be given to Type48 using whatever sign conven...
@juanf-belmonte Juan, I would guess that the TRNSYS engine is finding the HVAC library DLL before it finds the Type506_x64.dll file that you're crea...
@juanf-belmonte thanks for pointing this out. Oddly the code that is being distributed is correct. If you recompile that dll using the distributed cod...
@gehadrabee24 Gehad, the fields on the "derivatives" tab allow you to set the initial temperature of each node in the tank. A "derivative" in a Trn...