CESVA SC310, Руководство пользователя

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146
10.12 Function definitions
10.12.1 Average acceleration with frequency weighting W
m
and
evaluation time T
a
Wm
R.M.S. value of acceleration expressed in m/s
2
, defined by:
2
1
T
0
2
Wm
Wm
)d ( a
T
1
a
⎟⎟
⎠
⎞
⎜⎜
⎝
⎛
=
∫
t t
a
Wm
(t): instantaneous acceleration based on the time t and with frequency
weighting W
m
, in m/s
2
T: duration of the measurement (evaluation)
10.12.2 Acceleration level
L
Wm
R.M.S value of acceleration expressed in dB referred to 10
-6
m/s
2
, defined by:
o
Wm
a
a
log 20 L
Wm
=
a
Wm
: average acceleration with frequency weighting W
m
, in m/s
2
a
o
: reference acceleration 10
-6
m/s
2
10.12.3 Peak acceleration
PEAK Module maximum value of the instantaneous acceleration defined by:
( )
[ ]
T t
t
Wm
t a
=
=
=
0
max PEAK
a
Wm
(t): instantaneous acceleration based on the time t and with frequency
weighting W
m
, in m/s
2
T: duration of the measurement (evaluation)
10.12.4 Crest factor
CF Quotient between the peak acceleration and the RMS acceleration.
10.12.5 Maximum Transient Vibration Value
MTVV Maximum value of the acceleration with the frequency weighting W
m
and with
slow exponential averaging (
τ
= 1 s) in the evaluation time T. Expressed in m/s
2
.