For the SI units dialog box: the combined machine and load inertia coefficient J (kg.m2)

Hello.

I´m working with the asynchronouis mashine Block: https://de.mathworks.com/help/physmod/sps/powersys/ref/asynchronousmachine.html?searchHighlight=Three-Phase%20Asynchronous%20Machine&s_tid=doc_srchtitle and have a question about the parameters for the inertia.

In the description it says: For the SI units dialog box: the combined machine and load inertia coefficient J (kg.m2). So If I put on the shaft a disc with a weight of 27 kg, do I have also add the inertia of that disc in the parameters of the ASM block or is it enough just to put it as a load on the shaft?