Effective and modal mass for a cyclic symmetric model

Question - Why effective mass does not match total modal mass for a cyclic symmetric model? 

Answer - We can’t use the same guidelines about effective mass ratio for cyclic modal as we would with non-cyclic models. The effective mass won’t match for cases other than Harmonic Index=0.

As per the help document: For cyclic symmetric models, the participation factors are only provided for HI=0 and 1, and these values are multiplied by sqrt(N) and sqrt(N/2) to match a full 360-degree model.

This is described In Section 4.1.7, please see the section below:

Ansys Help : Modal Cyclic Symmetry Analysis .