08/2008
2 Machine information
2.2 Measurements and measurement series
© Siemens AG 2008 All Rights Reserved
ePS Network Services, Function Manual (FH) - Release 08/2008
2-45
2.2.6 Universal axis test
Description of functions
With the universal axis test different characteristics are calculated which describe
the mechanical properties of an axis.
Characteristic Meaning
Residual torque (Res)
This characteristic is not supported.
Coulomb friction (Coul)
The Coulomb friction describes the proportion of the
friction which is independent of the speed.
Mixed friction (Mix)
This characteristic is not supported.
Viscous friction (Visc)
This characteristic describes the proportion of the
friction which increases linear to the speed
Moment of inertia (Inr)
The characteristic describes the entire moment of
inertia that needs to be moved by the electrical
drive. This includes the moment of inertia of the
motor.
Torque offset (Const)
With axes which are pretensioned in one direction
(e.g. vertical axes) the characteristic indicates the
torque required for compensating for this pretension.
Coherence (K)
The coherence indicates how much a model param-
eterized with the calculated characteristics can
simulate the measured torque characteristics.
Circular deviation (G)
The characteristic describes the maximum position
deviation with axis movement on the basis of a ve-
locity profile. The calculation of the characteristic is
based on ISO 230-4 as is the case with the circular-
ity test.
The measurement type-relevant parameters are also specified.