M. To add a mass model reference load

A mass model reference load is added in the same way as any other reference load, but with the Loading Type set to Mass.

Either:

on the Loading ribbon tab, select the Reference Load Case tool in the Loading Specifications group

or
select the Definitions > Reference Load Definitions section of the Load & Definition dialog box and then click Add.

or
s

The Add New: Reference Load Definition dialog box opens.
(Optional) Type a reference load identification number in the Number field.
Tip: This number is incremented by one from any previously defined reference loads and typically does not need to be changed.
Select Mass as the Loading Type.
(Optional) Type a label in the Title For example, you may want to label the reference by typing Mass Model.
Click Add. The dialog box closes and a new reference load definition is added to the input file.