understanding balancing grade numbers 1

[BrianE22]

I'm trying to understand how balancing machines report "amount of unbalance". I understand a mass at an eccentricity, say so many grams at so many millimeters. But balance quality grades seem to be in units of velocity, say mm/sec. My confusion is this:

Is the balance quality grade a "velocity" in the sense of a velocity of a typical compliant bearing support that supports the spinning unbalanced armature?

 

[Tmoose]

Here is info based on IO 1940.

http://www.irdbalancing.com/downloads/techpaper1balqualityreqmts.pdf

BALANCE QUALITY GRADES
"Table 1 shows the balance quality grades for a variety of rotor types. The "G" number is the product of specific unbalance and the angular velocity of the rotor at maximum operating speed
and is a constant for rotors of the same type.
G = e x v = constant "

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If the rotor was in a weightless fixture AND mounted on SUPER critical (soft) springs the eccentricity and velocity might approach the theoretical values. If the balance machine (or actual machine) mounting is resonant it could be even higher.