Applications Of Vehicle Noise Measurement
The CR:261S is Ideal for static noise testing of cars, trucks & motorbikes in workshops, garages and test laboratories. The most common application for this is noise testing to ISO 5130:2007 Measurement of noise emitted by stationary road vehicles.
The CR:261S has been specifically designed to be used for vehicle noise measurements. In this application, the most commonly used measurement is the maximum sound level, or LAFmax. The instrument has two operating modes.
This is when the CR:261S is used without the remote control. In this mode, the display shows the current sound level, LAF, and the maximum sound level, LAFmax, recorded.
Remote Control Mode
The second measurement mode uses the remote control to start and stop the measurements.
With the remote control unit, ZL:261S, the noise tests can be carried out quickly and comfortably by one person alone – with a single button. When the remote control is pressed, the instrument will measure and record the LAFmax value. This mode allows noise measurements to be made in accordance with the requirements of ISO 5130:2007 as well as §29 StVZO.
The last three LAFmax measurements are displayed on the screen allowing the user to safely operate or monitor the vehicle under test whilst making the noise measurements.
Measurements to ISO 5130
ISO 5130:2007 requires three consecutive measurements to ensure repeatability. These measurements are taken at a specified engine speed, or RPM, and the maximum sound level produced during the test is taken. Once three valid measurements have been made, the highest is taken and used as the valid result. The microphone can be placed at the specified measurement position, typically 45o and 0.5m from the exhaust of the vehicle under test.
The CK:261S Measurement Kit includes a positioning template which can be used to ensure that the microphone capsule is set at the correct angle and distance from the vehicle exhaust.
The tripod included with the kit allows the sound level meter and microphone to be set at the correct height from the ground. The remote control allows the user to control the measurements whilst ensuring that the engine is at the correct RPM for the test.
The CR:261S can be supplied with a range of accessories and optional extras that allow the instrument to be used for various different applications.