Airmar has unveiled the TriSonic Smart Sensor. The sensor is designed for sailing and motor yachts with an NMEA-2000 network that wish to consolidate depth, temperature and speed data into a single transducer. What makes it special is not the number of measurements it takes, but the method of log measurement: instead of a mechanical wheel, the TriSonic uses ultrasound.
No cleaning of the impeller
Anyone familiar with a traditional log is usually aware of the downside: the paddle wheel must be able to turn freely. Shells, seaweed or dirt can distort the reading or bring it to a complete standstill. The TriSonic has no moving parts. According to Airmar, the signal processing adjusts the measurement to take account of speed, water depth and water quality.
The sensor measures speed through the water from 0.1 to 35 knots. It also provides depth readings from 0.6 to 100 metres, water temperature and attitude data for heel and trim. The readings are transmitted via NMEA 2000 to plotters and other instruments in the vehicle electrical system. The sensor thus complements systems such as those found, for example, in modern chartplotters in the cockpit be used.
Calibration via smartphone
The TriSonic connects via Bluetooth to the Airmar CAST app for iOS and Android. Here, you can set depth offsets, for example to display depth below the keel or from the water’s surface. The log can also be calibrated automatically.
For further customisation, according to Airmar product page You can store up to four heel angles and ten speed values. This is useful for sailing yachts, as the yacht’s attitude and the flow around the hull can affect speed measurements. The settings are stored in the sensor and are then available throughout the NMEA 2000 network.
The TriSonic is a retractable plastic through-hull transducer for GRP and metal hulls. It requires a 51-millimetre borehole and is designed to fit into most existing Airmar inch-sized housings. Whilst this may make replacement easier, it does not replace the need to check the installation position, hull material and existing sleeve.
Of interest for retrofitting
The TriSonic really comes into its own where regular maintenance of a paddlewheel log is difficult, for example in areas with heavy vegetation. The ultrasonic transducer combines four measuring functions in a retractable through-hull transducer and transmits the data directly to the NMEA-2000 network. Whilst this does not necessarily reduce the number of individual sensors on the hull in every system, it can make retrofitting a more straightforward process.
For yacht owners who are already connecting their instruments or transferring data to a Smartboat system for remote monitoring When it comes to integration, the TriSonic is an attractive retrofit option, particularly due to its low-maintenance speed measurement.
Book recommendation
Theory and Practice of Vehicle Electrical Systems explains the electrical equipment on a yacht, from batteries and charging systems to installation and troubleshooting. The book also covers log, depth sounder and chart plotter. For yacht owners who wish to integrate a new sensor into the NMEA-2000 network or gain a better understanding of the on-board electrical system during a retrofit, it provides the fundamentals for planning, selecting materials and ensuring safe implementation.
What experience have you had with paddlewheel logs and fouling, and would an ultrasonic transducer be a viable alternative for your yacht?
Michael Rinck
Redakteur Test & Technik
