Press OK to start measuring. Measurement lasts for 10 seconds. During this period an average
of all the varying sound pressure levels detected, called 'L
ry for later reporting. Background noise that is too high (less than 10 dB below a measurement)
will be marked in the printout together with the background noise value.
If the environmental properties of a test site do not change, then background noise measure-
ments are only required occasionally. Background noise measurements must be taken if and
when conditions differ from previous tests, such as change of location, or change of surround-
ing traffic, population, objects, etc.
Setup
In order to ensure correct measurement results during acoustic detection as well as adherence to
most international and national standards, the sound level meter must be calibrated before meas-
uring sound levels. Proper calibration procedures are described in "Calibration" on page 24.
Before a measurement sequence can begin, specific measurement parameters must be defined,
which identify the type of vehicle to be tested and the sound level maximum to which the
exhaust system must comply. To configure the necessary measurement parameters, switch on
the controller unit (if not already on) and, using
operation menu. Press OK to confirm. Instructions on individual parameter setups follow below.
Note: Press OK to forward through the various parameters. You exit the Setup menu once you
have reached the last parameter.
Engine Speed
Set the RPM value, which will trigger the system to automatically begin sound level measure-
ments:
1) Press
to scroll through the RPM trigger value options.
The default value is: 3000 o/min.
The value increases/decreases in increments of 5 o/min. Holding down an arrow key speeds
up the updates to 100 o/min at a time.
2) Press OK to confirm your selection and proceed to the next parameter.
Measurement of
background noise.
PART 1
English
' is taken and saved to the memo-
Aeq
, select Setup under the main
19