# MATLAB: Basic help with simulink model

I am trying to run this model but what are the PIn and POut blocks in the image below. Also how do I create the efficiency block? Please help as I am new to this.

• Hi,
to measure an efficiency of a technical structure you have to calculate the ratio of the power you get out of this technical structure (Pout) and the power you put into this technical structure (Pin). If you have both of these values you can calculate the ratio of them
eta = Pout / Pin
and you have the efficiency of this technical structure. So these values are the power values of your system.
When you double click on the Pin or the Pout Blocks in the Simulink example the corresponding subsystems open and you see whats going on in there. For Pin and Pout it are power sensors:
Same when you click on the claculate efficiency block - the subsystem opens and you find how the block was built.
Another way to built this function would be
matlabFunctionBlock
command - if you have symbolic toolbox.
Best regards
Stephan