Hi Mukendi,
I understand that you are getting error as you have not added the solver configuration block to your physical network.
Each physical network represented by a connected Simscape block diagram requires solver settings information for simulation. The Solver Configuration block specifies the solver parameters that your model needs before you can begin simulation.
Every physical network needs a Solver Configuration block. If you have several physical networks and some Simulink Blocks in between you will have to use one Solver Configuration for each physical network.
Refer to following documentation for further understanding on Simscape and Solver configuration:
I hope this helps.
Warm Regards,
Pranjal.
