Screen Indicators - Quest SD-200 Manual De Usuario

6 Operating

Screen indicators

Screen indicators are a type of notification identifying measurement parameters &/or screen icons.
Indicators Explanation
SPL Sound pressure level - The basic measure of noise loudness expressed in decibels. SPL
uses the ratio between a reference level of 20 microPascals (.00002 Pascals) and the level
being measured. It is displayed in decibels (dB).
MAX Maximum sound level - The highest SPL measured during integrating period.
MIN Minimum sound level - The lowest SPL measured during integrating period.
L L Equivalent pressure sound level/Average sound pressure level – The true equivalent
EQ/ AVG
sound level (or average SPL) measured over the integrating period. The term L
when 3 dB exchange rate is applied; The L
Battery indicator – There are two battery indicator states.
 When battery power icon appears, this indicates the instrument has low power and needs
Battery
to be charged.
power
 Battery power icon flashing indicates the battery is charging.
Run indicator - Signifies that you are measuring L
Run screens over the Run-Time
Detection icon – Appears when viewing the LED Alert screen. (Note: LEDs will flash if set
points are met or exceeded. See "LED Alert" for more info.
Detection
Run-Time – Indicates the time elapsed from the start of the run mode which is used to
calculate the L
and seconds and then changes to hours and minutes when 20 minutes is reached. It will
Run-Time
display hours only after 20 hours.
OL Overload – Indicates that the dB has exceeded the range of SD-200 (40–130 dB).
UR
Under Range – Indicates that the displayed measurement is below the linearity range
(45–130 dB).
F/S Fast/Slow time response - The response time setting determines how quickly the unit
responds to fluctuating noise. Typically, noise is not constant. If you were to try to read the
sound level without a response time, the readings would fluctuate so much that determining
the actual level would be extremely difficult. While the terms slow and fast have very specific
meanings (time constraints), they work very much as you would expect. The fast response
would result in a more fluctuating sound level reading than would the slow response. (See
Specifications, "Time Response")
A/C A frequency weighting or C frequency weighting - These are frequency filters that
approximate the equal loudness response of human hearing at low, medium, and high
SPL's. A frequency weighting is the most commonly used filter defined in the international
standard IEC 61672:2003. Common applications of A weighting include industrial noise
applications and community noise regulations (such as: manufacturing noise or machine
shop monitoring.) The A frequency weighted filter makes the sound level meter respond
closer to the way the human ear responds to noise at lower levels. It attenuates the low
frequency noise below several hundred Hertz as well as the high frequency above six
thousand Hertz. C frequency weighting is intended to represent how the ear responds to very
high levels.
/L , LED Alert
EQ AVG
Table 1-2: Screen indicators
is used when 5 dB exchange rate is applied.
AVG
/L
EQ AVG
.
, MAX, and MIN values. Run-Time starts as minutes
is used
EQ
, LED Alert , MAX, and MIN