Magtrol TM 301, Руководство пользователя

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. The natural torsional frequency of the drive train is lower due to the presence of the TM
Torque Transducer. The system’s own natural frequency must then be recalculated to de-
termine the influence of the TM Transducer.
The torsional spring consists only of the deformation zone of the measuring shaft. The torsional stiffness
values (C
t
) are indicated in the technical data sheets (
see section 1.3 - Datasheet
). J
1
and J
2
are the two mo-
ments of inertia acting on each side of the deformation zone. They can be calculated by adding the mo-
ments of inertia of each individual element. The moment of inertia of the measuring shaft is also indicated
in the data sheet. Consult with the suppliers of the couplings, driving element(s) and driven element(s) in
order to obtain the inertia ratings of these drive train components.
The natural torsional frequency (f
0
) determines the following:
▪
the frequency response of the torque measuring system
▪
whether or not rapid variations in torque can be accurately sensed
▪ whether or not the torque signal is amplified or attenuated by the dynamics of the drive train
The transfer response is plotted (
see Fig.2-9
) for various quality factor values (Q), which are dependent
upon the amount of damping in the torsional system. The graph charts the factor by which the torque will
be amplified, depending on the frequency of the torsional oscillations.
Fig.2-9 Frequency Response Graph
. The system should be configured and operated in a manner so that the natural frequency
is avoided in everyday operation. The transfer function should be as close to 1 as possible.
Consequentially, the frequency of the drive train torsional oscillations should be less than
~0.5 f
0
.
NOTICE
0
2
1
4
6
8
10
12
14
16
18
20
22
0.2 0 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
F
F
0
A(f)
A
0
Q = 30 Q = 30
Q = 10 Q = 10
Q = 3 Q = 3
Q = 1 Q = 1
NOTICE
21
TM
series
INSTALLATION / CONFIGURATION