Minimum Number of Samples per Signal with multirate model

Question: I am working on a multirate model, but why cannot I set the Number of Samples per Signal (NSS) to 1?

Answer: Due to the existence of blocks/parts running at a multiple of your fundamental time step, your model will actually have complete results and update to the console at a rate of the LARGEST time step in your model. Therefore, the minimum NSS should be given in the following equation:

NSS_min=Ts_max/Ts, where Ts_max is the largest sample time among all blocks in your model and Ts is the fundamental time step of your model. 

Also,  NSS should be also a multiple integer of the NSS_min.

For example, if your model has three sample times: 0.001s, 0.002s, and 0.004s, the minimum NSS is 4 and you CANNOT set an NSS to 25, which is not a multiple integer of 4.