The SWS-100 and SWS-050 are optimised for use in applications where accurate and reliable visibility measurements are required with the addition of fundamental WMO 4680 precipitation codes. The forward scatter design allows the sensor to be compact whilst the inclusion of serial, analogue and relay outputs makes these sensors easy to interface to any system.
The measurement of visibility by forward scatter as used by the SWS-100 and SWS-050 is now widely accepted and seen as having significant advantages over more traditional techniques such as the use of transmissometers or backscatter sensors. The SWS sensors are compact, very easy to install, require little maintenance and have a maximum visibility range of 10m to 75km for the SWS-100 and 10m to 40km for the SWS-050. The factory calibration of the SWS sensor family is undertaken in accordance with the recommendations of ICAO 9328 and is fully traceable to a highly respected national weather service transmissometer.
Visibility measurements are reported as Meteorological Optical Range (MOR). The reporting of atmospheric Extinction Coefficient (EXCO) can be selected by the user if required. The inclusion of hood heating and advanced self-test features as standard makes the SWS-050 Biral's most cost effective solution for visibility measurement, and window contamination monitoring and compensation ensures the results remain accurate even in challenging conditions.
Present weather reporting in some applications is useful for finding out what is causing the reduction in visibility as this may fundamentally change the action to be taken by the user. The SWS-100 therefore has the ability to identify and report the presence of drizzle, rain and snow precipitation types using WMO Table 4680 codes. Fog, haze, and unidentified precipitation codes are also reported.
The SWS-100 is used by many global national weather services, including the United Kingdom's MetOffice, as part of synoptic monitoring networks due to its wide measurement range, reliability and measurement accuracy.
The SWS-100 and SWS-050 are very versatile sensors suited to a very wide variety of applications.