Description
    The 915-RG RAINFALL SENSOR is a tipping bucket type rain sensor, to WMO standard. It
has been proven over a wide range of climate conditions.
Operation
    Rainfall collected by the funnel is passed via a filtered siphon to ensure a constant delivery rate to the tipping bucket assembly. This ensures accurate metering up to 200 mm/ hour rainfall rates.
    Each time the bucket tips and empties a magnet momentarily closes a reed switch. Switch
closures can be monitored by remote equipment to measure rainfall rate and total.
Construction
    All materials used in manufacture are resistant to corrosion or are coated with corrosion resistant finishes, thus ensuring maintenance free operation in all environments. A fine stainless steel mesh protects openings from ingress of insects etc. For correct operation, this type of rain sensor must be mounted in a level position.
    A "Bull’s-eye" level is incorporated to facilitate levelling. 10 metres of screened cable is fitted.
Calibration
    The 915 is set at the factory for 0.2 mm/tip. However, the setting can be set in the range 0.2
to 0.5 mm/tip by simple mechanical adjustment. The calibration procedure is simple enough to be easily performed on site.
Application
    This type of sensor can be used with Automatic Weather Stations, computers and digital
totalisers. Care should be taken to "de-bounce" the contacts and provide lightning protection for the interface circuitry.
Options
    A heated version is available for cold climate application. A leaf catcher filter option
prevents leaves and other debris from clogging the funnel.