Transducers & Sensors for Boats

Why do I need a transducer or sensor for my boat?

- Keep a steady eye on the most important data -

Transducers and sensors provide important information for navigation and orientation on the water, such as wind strength and direction, water depth and speed. Some are boat speed sensors (log), depth transducers and water temperature sensors in one device, so-called triducers. The NAVICO Forward Scan transducer, for example, provides you with a 2D sonar image of the sea bed in front of your boat. Anglers use high-resolution depth sounders (fish finders) that show show the bottom of the water in more detail or even project the target fish directly onto the display.

How do I add a transducer to my boat?

- The right choice depends on your boat material and shape -

Wind sensors are usually mounted on the mast where they record the wind speed there. All the electronics needed to record the data are integrated into the wind sensor. In certain cases, sensors for speed (log), water depth sounders (echo sounder module) and water temperature can be attached to the inside of the hull. In most cases, however, the hull material can interfere with the transmission signal, so sensors are used as through-hull sensors in the hull below the waterline. They send their signal directly into the water and thus achieve the best results. Boat parts such as propellers or rudders create turbulence in the water, which can also interfere with the transducer signal, which is why through-hull transducers are always used in front of the keel. For boats that are often transported on trailers, manufacturers have developed particularly flat versions that cannot get caught on trailer rods when slipping.

Make sure you buy the right transducer and pay particular attention to material type! Transducers with a plastic housing are suitable for boat hulls made of GRP (plastic) or metal. Wood, on the other hand can shrink or swell and could damage the plastic case. Bronze is therefore the ideal sensor material for a wooden boat. However, never install a bronze through-hull transducer in an aluminium boat, because aluminium and bronze attack each other in salt water. Also, you should never install a steel case transducer in a positive ground metal boat. If so, then an isolating fairing block must be used. For certain boat designs that have little space available inside (usually fishing boats), through-hull transducers with a tilted sensor element are available on the market. These transducers are placed flat against the hull and do not require a fairing block. The special feature of these types of transducer is that the transmitting element is installed in such a way to compensate for the deadrise of the hull, so that the sensor cone always radiates vertically downwards.

If you don't want to drill a hole in your hull, use an inboard transducer. These are attached directly to the hull inside the boat and emit through the hull. However, they only work on GRP boats and not with wood, steel, aluminium or composite construction. The disadvantage is that they are less powerful. Some sonar transducers can be mounted on the transom of the boat below the waterline. They are made of plastic and are therefore usually much cheaper to buy than other models. Requirements are that the boat should not be longer than eight meters and the drive must be behind the transom, such as on smaller fishing boats and motor boats with outboards , jet or Z-drives.

You might also be interested in: related accessories and information

You will find useful accessories in the categories NMEA2000 cables & connectors as well as boat instruments Also take a look at our guide: How to find and install the right transducer.