A new infrared optical rain gauge designed to replace the limitations of tipping bucket gauges, has been unveiled by designer and manufacturer of meteorological and environmental measurement instruments, Gill Instruments. 

Mechanical tipping bucket gauges are prone to clogging, mechanical drift (requiring frequent calibration for reliable data), and under-counting during high-intensity rainfall, leading to maintenance demands and uncertainty of data accuracy.

Gill’s TruMet PW100 optical rain gauge uses a solid-state optical measurement principle rather than mechanical collection. LEDs create a beam of light across a defined sensing area, and a receiver monitors interruptions in the beam caused by rainfall.

By analysing the size and velocity of droplets, the system is engineered to accurately measure rainfall accumulation and filter out non-rain interference, such as insects or debris.

The device is designed with no moving parts, collection funnel, or tipping mechanism, reducing the risk of failure and the need for costly maintenance.

The gauge is suited to applications such as:

• meteorological and hydrological networks
• flood forecasting and early-warning systems
• smart city and urban drainage monitoring
• transport, aviation and infrastructure operations
• renewable energy and environmental monitoring

“This optical rain gauge delivers trusted accuracy without moving parts and minimal maintenance, which fundamentally changes how rain data can be collected at scale,” said Gill product manager Greg Koch.

When installed, the unit outputs the standard pulse signal, which is an electronic output used by weather equipment, that tipping bucket rain gauges use, so it can be deployed as a direct replacement within existing monitoring networks without the need for system changes or retraining.

The company asserts that future software and hardware updates will further expand the optical rain gauge's capabilities and data options.

The TruMet PW100 optical rain gauge will be available both as a standalone rainfall sensor, and as an integrated option within Gill’s MaxiMet product line, including the upcoming GMX603 unit, which incorporates the optical rainfall technology into a compact weather station, an instrument that measures multiple meteorological parameters.