35
SVANTEK 977W User Manual
Note: It is not possible to set the integration period less than 1 minute if Repetition Cycle is set to
Inf. This is specific of Welmec series of the instruments.
To set the integration period the user should define the required hours, minutes
and seconds fields.
The appropriate field may be selected by pressing the
◄ or ► push-
buttons.
Value of hour, minute and second is changing by means of the
▲
or
▼
push- buttons.
Number of measurement repetitions
The
Repetition Cycles
position defines the number of cycles (with the
measurement period defined by
Integration Period
) to be performed by the
instrument. The
Repetition Cycles
number values are within the limits [1, 1000].
Detector type
The
RMS Integration
position defines the detector type for the calculations of
the
Leq
,
LEPd
,
LN%
and
Sel
functions. Two options are available: linear (
Lin
)
and exponential (
Exp
). The formulae used for the
Leq
calculation are given in
Appendix D.
Selecting
Lin
is required to obtain the true RMS value of the measured signal. When this option is selected the
value of the
Leq
,
LEPd
,
LN%
and
Sel
functions do not depend on the detector time constant:
Fast
,
Slow
or
Impulse
(the results are displayed without the indicator of the detectors selected in the profiles). In this case, the
indicator
Lin.
(or
L
) is displayed in the different modes of the result presentation.
Selecting
Exp
enables the user to fulfil the requirements of other standards for the time averaged
Leq
measurements. When this option is selected the value of the
Leq, LEPd, LN%
and
Sel
function depends on the
detector time constant (
Slow
,
Fast
,
Impulse
). The results are displayed with the indicator of the detectors
selected in the profiles (
path: <Menu> / Measurement / Profiles
).
Statistic calculation
The
Statistics
position defines the method for calculation of the statistical
results. The statistics for profiles will be calculated based on RMS results with
linear detector (
Lin
) or exponential detector (
Exp
), e.g. Impulse, Fast or Slow,
defined in the
Profiles
list.
Day time limits
The
Day Time Limits
position appears only in Sound modes and enables the
user to select the definition of the day and night periods required by the local
standards. These limits are used for the calculation of the
Lden
function
(cf. App. D for the definition). Two options are available:
6
–18 h
and
7
–19 h
.
