Svantek SVAN 958A - D.2. VIBRATION LEVEL METER

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SVAN 958A User Manual
D.2. VIBRATION LEVEL METER
D.2.1 Basic terms and definitions (VLM mode)
T
Current time period of the measurement in seconds.
T
0
Reference duration of 28 800 seconds (8 hours)
T
E
Exposure time

Exponential time constant in seconds for the giving time-weighting. The following time
constants are available: 100 ms, 125 ms, 200 ms, 500 ms, 1.0 s, 2.0 s, 5.0 s, 10.0 s.
W
Frequency-weighting filter (HP, HP1, HP3, HP10, Vel1, Vel3, Vel10, VelMF, Dil1, Dil3, Dil10,
or Wh).
( )
ta
W
Instantaneous frequency-weighted signal with the weighting filter W.
( )
ta
W 
Instantaneous frequency and time-
weighted signal with the weighting
filter W and time constant

calculated from the equation:
( ) ( )
( )

−
  =
 − −


t
/t
dea
1
ta
2
WW
,
where:

– variable of integration.
( )
tv
Instantaneous vibration signal
depends on the
<RMS Integration> parameter:
( )
( )
( )



=
=

=
Exp nIntegratioRMS
Lin nIntegratioRMS
ta
ta
tv
W
W
AEQ
Acceleration Equivalent Vector of
RMS values taken from three axis
(equivalent to ahv when Wh filter is
applied)
2
z
2
y
2
x
RMSRMSRMSAEQ + + =
VDV
WB
Vibration dose value for Whole-
body
 
zyxWB
VDV,VDV4.1,VDV4,1maxVDV =
RMS
WB
Root Mean Square for Whole-body
 
zyxWB
RMS,RMS4.1,RMS4,1maxRMS =
EAV
Exposure Action Value – constant
value defined by local standards
expressed in
2
s
m
or in
75.1
s
m