Svantek SVAN 958A - Page 188

188
SVAN 958A User Manual
Overload detector
The instrument has the built-in overload detectors. Both A/D converter and input amplifier overload conditions
are detected. The overload in the measurement channel (in its analogue part) and the overload of the
analogue / digital converter are both detected. The “overload” indication appears when the input signal
amplitude is 0.5 dB above the declared “Peak measurement range”.
Underrange detector
The instrument has the built-in under-range detector. The “underrange” indication appears when the Leq value
for the elapsed time or the last second SPL value is below the lower linear operating range.
Time weighting characteristics (Exponential averaging)
Slow “S“ according to IEC 61672 Class 1, Equivalent Time Constant 1000 ms
Fast “F” according to IEC 61672 Class 1, Equivalent Time Constant 125 ms
Impulse “I” according to IEC 60804 Class 1, Equivalent Time Constant 35 ms, Hold Time 1500 s
Reference conditions as per IEC 61672-1:2013
• Class of the acoustic field Free field
• Reference acoustic pressure 114.0 dB (related to 20 Pa)
• Reference frequency 1000 Hz
• Reference temperature +23°C
• Reference relative humidity 50 %
• Reference static pressure 1013.25 hPa
• Reference incidence direction perpendicular to the microphone diaphragm.
Maximum peak voltage 30 V Peak-Peak (Maximum peak voltage of input sinusoidal
signal, which can be lead to the SLM without destruction the
meter)
Warm-up time 1 min. (for 0.1 dB accuracy)
Typical stabilization time after change in
environmental conditions by 20C
1 hour
Time shift after completion of a
measurement, before a measurement is
shown
≤ 1 sec
Nominal delay between operating of the
<Start> (Reset) key and beginning of a
new measurement
≥ 1 sec
Note: When SVAN 958A is moved from a warm environment with high humidity to a colder
environment, care should be taken not to produce condensation inside the instrument. In this case,
much longer stabilization periods may be necessary.