Navman Marine 3100 Series Instruments

Keep tabs on depth, speed and more with this cooperative flock of instruments.

Devices that convey wind velocity, hull speed and depth information are the backbone of a boat’s instrument suite. Though today’s units may look very much like those of 10 or more years ago, those in Navman’s 3100 series prove this class has benefited significantly from advances in electronic technology. Even better, they can operate in conjunction with Navman’s fishfinders and chart plotters. I tested them with the Fish 4500 and Tracker 5600, so we’ll take a look at those units, as well.

I began my exploration of the Wind 3150, Speed 3100 and Depth 3100 by mounting them in a temporary instrument panel. It is clear the designers understand the challenge of installing this type of equipment on a boat. Each mounts in a 2-inch-diameter hole and is secured by a rear-mounted, threaded retaining ring. Two cables protrude from each unit: one for power and data from NMEA 0183 devices and Navman’s proprietary NavBus; the other terminated in a color-coded sensor connector, eliminating the risk of plugging the wrong sensor into a display. Each unit is 4.4 inches square and protrudes only seven-eighths of an inch from the panel. These instruments are typically mounted together, a process simplified with the included mounting template. The instruments are waterproof when installed in the panel. Their cleverly designed cases combine a hard-plastic front bezel with a soft-plastic rear section, which has a raised, narrow edge that serves as a deformable gasket, sealing the case against the panel without the need for a conventional, separate gasket.

The Speed 3100 and Depth 3100 use identical monochromatic, sunlight-readable, 4-inch LCDs, which display data in easy-to-read, 11/2-inch-tall numerals. (Backlighting is adjustable.) The functions of each instrument are controlled via four symbol-marked keys arrayed along the lower edge of the bezel. When multiple instruments are installed and linked to one another, a single instrument can adjust backlighting for all. The instruments can also share transducers-the Depth 3100, for example, can use the sonar transducer from the Fish 4500. The NMEA bus allows exchange of data with other onboard systems, too. The Speed 3100 can display ground data from a GPS in lieu of information from its through-hull speed/temperature transducer, and the Wind 3150 can use SOG data to compute true wind direction and speed.


The Depth 3100 displays information in meters, feet or fathoms and provides shallow- and deep-water alarms. Range of depth is up to 400 feet, depending on your transducer and the clarity of the water. The programmable keel-offset adjustment range is up to 9.9 feet. An output is provided for an external alarm light or buzzer.

The Speed 3100’s paddlewheel through-hull transducer contains a water-temperature sensor. Speed can be displayed in knots, miles per hour or kilometers per hour up to 50 knots. A programmable damping function with five speed-averaging times-6,12,18, 24 and 30 seconds-smoothes the information. Display of maximum or average speed is available at the push of a button. Engaging the “trim speed mode resets the display to emphasize subsequent changes in velocity.

The Wind 3150 combines a 360-degree analog wind-direction pointer and a multifunction LCD. The LCD, normally used to display wind speed, can also show relative wind angle in degrees. Since information about the boat’s speed is available on the NavBus, the system can display true and relative wind direction and speed. The Wind 3150 also will record maximum wind speed; it includes an adjustable wind-speed alarm. All necessary installation calibrations-those regarding wind angle, wind speed and wind-speed damping-are easily carried out from the control panel. The system’s masthead sensor is well designed and easy as any to mount. If I could add one feature to the Wind 3150, it would be a means to force the wind vane and anemometer cups to rotate. On more than one occasion, we had to climb the mast of our boat to free them from the grip of a spider’s clever web-rigging efforts.


In sum, the three Navman 3100-series instruments I tested provide the basic information helmsmen need aboard virtually all yachts, power or sail. The displays are easy to read, the data is suitably stabilized, and installation is outstandingly easy. They are an excellent value.

Navman’s Tracker 5600 chart plotter (Field Test, January 2003) and Fish 4500 Fishfinder use a mounting method different from the 3100-series instruments, thanks to their larger LCDs and additional control buttons. The Tracker 5600 has a 6.4-inch, 234-by-320-pixel color TFT LCD. The Fish 4500 has a 5-inch 320-by-234-pixel color TFT LCD. Both have the same soft-plastic back used in the 3100 series, simplifying surface mounting. The quick-removal pedestal mounts, supplied with both units, provide an alternative to surface mounting. The connector cover, attached to the sensor cable, protects the connector pins when the units have been removed for stowage.

The modest size of the Fish 4500 is not reflected in its capability or performance, both of which are first-class. The sonar transmitter delivers up to 600 watts RMS and powers a 50/200 kHz transducer. The receiver’s specifications-its sensitivity of better than 10 microvolts RMS and 120-decibel dynamic range, in particular-provide excellent performance. Like all of Navman’s 4000-series fishfinders, the Fish 4500 processes sonar reflection signals using the company’s SBN technology, a proprietary sonar-processing software that enhances signals while reducing interference. The need for frequent adjustment of the receiver gain and threshold controls is reduced, allowing the user to concentrate on running the boat and viewing the data.


Nine keys and a four-way cursor pad control the Fish 4500. The keys are large, well marked and easy to operate. Key markings and functions are clear, making it possible to operate the unit with minimal reliance on the instruction manual. The function of the Escape key is particularly well thought out-a maximum of three strokes will restore the original screen display, making it just about impossible to get lost in the system’s command tree.

The initial setup process addresses six areas: system, sonar, units, alarms, “comms (communication settings for units operated in conjunction with other Navman or NMEA 0183 equipment) and calibrations. The highly intuitive design of the user interface makes the setup process quick and painless. The comprehensive alarm menu includes notification of shallow and deep water, detection of return echoes (with a signal profile that determines if the echoes are caused by fish), monitoring of DC power-supply voltage, and triggers pertaining to water temperature. The Fish 4500, like the Tracker 5600, accepts data from one or two gasoline-engine fuel-flow transducers, making it possible to optimize fuel economy and account for the effects of wind and current. The availability of this program on both instruments will be useful when one is being used to display other data. Navman, however, should consider expanding the system to accommodate diesel power.

My retest of the Tracker 5600 confirmed my first conclusion: This is a good thing in a small package. Its performance as a WAAS/EGNOS-capable GPS receiver and chart plotter left nothing to be desired for a unit of its size and price.


With its precise data and comprehensive array of adjustable alarms, the Navman system is of great value. If properly configured, the Tracker 5600, Fish 4500 and 3100-series instruments will enable yachtsmen to spend less time deciphering displays and more time looking out for the safety of their boats-a win-win situation for everyone on the water.

Prices: Speed 3100: $269.95; Depth 3100: $269.95; Wind 3150: $629.95; Fish 4500: $699.95; Tracker 5600: $999.95. n Contact: Navman Marine Electronics, (866) 628-6261;

Click here to buy Navman products.


Email Newsletters and Special Offers

Sign up for Yachting emails to receive the latest news on new boats and technology, advice on seamanship skills and great nautical destinations, as well as special offers on behalf of Yachting’s partners.

By signing up you agree to receive communications from Yachting and select partners in accordance with our Privacy Policy. You may opt out of email messages/withdraw consent at any time.

More Yachts