SSP Co-simulating two FMUs creates "Unknown signal" error.

[opwwork]

Description

Hello All, please be lenient if I misposted this as a bug if it indeed is a "user error".
However I have tried to reproduce my current issue with OMSimulator in another tool (Matlab/Simulink as well as pyfmi), where it would principally work.

Basically: I have generated two FMUs

• a Dc motor and
• some simple Mechanics with a switch

which I would like to connect in an SSP to create the expected behavior:

1. The Mechanics send a boolean signal to the Dc motor
2. This causes the Dc motor to rotate
3. The rotation is a real signal sent back to the Mechanics that reduce an internal value
4. As soon as an internal limit is reached, the Mechanics switch the boolean signal off
5. The Dc motor should stop rotating

However running the same setup within OMSimulator always generates an error:

Looking for solutions, removing the rotation signal OR the boolean signal cause it to complete, removing the error (and of course also the expected behavior, becasue the motor never stops):

Steps to reproduce the behavior

1. Start OMEdit
2. New SSP Model
3. Add SSP Submodel "dcmotor.fmu"
4. Add SSP Submodel "newmechanics_inverted.fmu"
5. Connect Submodels accordingly (see 2nd image)
6. Execute simulation
7. Error: Unknown Signal "twofmu.Root.newmechanics_inverted.mechanicalsignalout"

(both FMUs are attached in the zip file as well as the working python code and the SSP)

2-fmu-test.zip

Expected behavior

Running the two FMUs in pyfmi generated the expected result:

Version and OS

• Version: OMS Server 2.1.1.post188
• OS: Win10, 64bit