Svantek SV 104BIS, Руководство пользователя

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129 SV 104BIS User Manual
Measured quantities
The measured quantities for DOSE METER mode are: Time, Lpeak, Lmax, Lmin, SPL ( L ) , DOSE, D_8h,
PrDOSE, Lav, Leq, SEL ( LE ) , SEL8, E, E_8h, LEPd, PSEL, Ltm3, Ltm5, Leq statistics ( Ln ) , PTC, PTP, ULT,
TWA, PrTWA, Lc-a. Definitions for measured quantities are given in Appendix D.
Conformance testing
This chapter contains the information needed to conduct conformance testing according to the specified
standards.
Mounting for acoustical tests The microphone must be mounted on the instrument.
Electrical substitute for the microphone To obtain a BNC Class electrical input, the microphone
must be replaced by an electrical microphone impedance
adapter SC 104AT
before turning the instrument on . Total
microphone substitute impedance is 125
Ω.
Note: The recommended time interval for periodic test of noise exposure meter for checking its
acoustic and electrical working characteristics is one year.
Note: For the conformance electrical tests the Microphone Compensation must be disabled (see
Chapter 4.15 ).
Note: For the conformance acoustical tests with the microphone the Microphone Compensation
must be enabled (see Chapter 4.15 ).
For the comparison coupler evaluation, the Free Field compensation must be disabled.
For the free filed evaluation, the Free Filed compensation must be enabled.
Linear Operating Ranges
The starting point at which tests of level linearity shall begin is 114.0 dB for the frequencies specifies below.
Linear operating range for the sinusoidal signal and microphone sensitivity 1 mV/Pa
Single measuring range
–
see table below.
Table C.1 Linear operating ranges for Leq
[dB]
L
AS/F
L
CS/F
L
ZS/F
L
AeqT
L
CeqT
L
AE
L
Cpeak
(t
int
= 2 s)
from to from to from to from to from to from to from to
31.5 Hz 53 100.6 55 137 65 138 53 100.6 53 137 53 103.6 56 140
500
Hz 53 136.8 55 140 65 138 53 136.8 53 140 53 139.8 56 143
1 kHz 53 140 55 140 65 138 53 140 53 140 53 143 56 143
4 kHz 53 141 55 139.2 65 138 53 141 53 139.2 53 144 56 142.2
8 kHz 53 138.9 55 137 65 138 53 138.9 53 137 53 141.9 56 141
Note: For the signals with the crest factor n >1.41 upper measuring range of the RMS ( LEQ and
SPL ) is reduced. The valid upper limit can be calculated according to the below given formula:
𝑨
𝒏
= 𝟏𝟒𝟎 − 𝟐𝟎 𝒍𝒐𝒈(𝒏/√𝟐)
, where A is the upper limit for the sinusoidal signal
Example: For the crest factor n = 10 the upper limit is A10 = 123 dB