CR:243/4 "Noise Pole" Noise Monitor
The CR:243/4 "Noise Pole" is a Noise Monitoring Terminal designed for permanent installation on an Industry Standard lighting pole.
This makes the CR:243/4 ideal for installation in sensitive areas where the CR:243/1 Noise Monitor would be obtrusive, or where there is a risk of damage or vandalism. The CR:243/4 unit has an integral microphone system, which provides the acoustic signals to the main instrument, and allows fully automatic calibration using an electrostatic actuator system.
The CR:243/4 has been designed to be operational for many years, and therefore has significant weather protection as well as physical security. The enclosure is sealed to IP65 standards, and all connections to the unit are made by sealed, armoured conduit to prevent damage or water ingress.
The CR:243/4 uses exactly the same processing system and microphone system as the CR:243/1 Noise Monitor but the system is completely integrated into a single enclosure.
The design of the CR:243/4 is to allow the instrument to operate unattended for long periods of time. Therefore the instrument can store large 
amounts of data internally.
When required, this data can be downloaded to the host computer. This allows dial up telephone lines to be used for communications, and means that the noise monitor need only be contacted when required, typically once every day. However, if communication cannot be made with the instrument, the large memory allows measurements to be made without loss of information.
The standard CR:243/4 can provide most of the parameters required for Environmental Noise Measurement, but these can be supplemented by various options and modules. Please contact Cirrus Research plc for details.
Advanced recognition templates are used to monitor specific noise events, and the multiple Environmental groups allow continuous measurement of the noise climate. The unit will also remove recognised noise events from the measured noise climate information, showing the impact of those noise events.
The instrument will also store and download diagnostic information, as well as any additional measurement functions that have been added to the standard unit
Many of the Cirrus Research plc environmental noise monitoring instruments are capable of support additional data inputs.
An Environmental Noise Monitoring application using Cirrus Research plc equipment can be built as a modular system, with additional monitors and special measurements added as required. A range of software solutions is available to support the hardware.
The CR:243/1 and CR:245/3 instrument have been type approved with their associated accessories by the PTB in Germany. In addition to individual component type approval, systems have also been passed by the PTB after installation. This requires the entire system from the microphone capsule to the computer with the software to provide consistent, accurate information, and represent a significant achievement.
Further details of the PTB type approval are available on request from Cirrus Research plc.
- Links:
Product Datasheets: CR:243/4 "Noise Pole" Noise Monitoring Terminal- Product Information: CR:243/1 Noise Monitoring Terminal
- Product Information: CR:245/3 Portable Noise Monitor
- Product Datasheets: CR:243/1 Noise Monitoring Terminal
- Product Datasheets: CR:245/3 Portable Noise Monitor
