Important
The choice, location, angle and installation of the instrument & transducers are critical to performance of the system as intended. Follow instructions in this manual carefully. If in doubt, consult your Northstar dealer.
Ensure that any holes cut are in a safe position and will not weaken the boat’s structure. If in doubt, consult a qualified boat builder.
Do not install plastic through hull transducers in solid wooden hulls. Leaking through the hull may result.
Do not install bronze transducers in metal hulls. This will cause electrolytic corrosion that may result in damage to the hull or transducer.
Sonar Performance: The accuracy of the sonar depth display can be affected by many factors, including the type and location of the transducer and water conditions. Ensure that the transducer is located and used correctly.
Global Positioning System: The Global Positioning System (GPS) is operated by the US Government which is solely responsible for its operation, accuracy and maintenance. The GPS system is subject to changes which could affect the accuracy and performance of all GPS equipment anywhere in the world including the 657. Whilst the Northstar 657 is a precision navigation instrument, it can be misused or misinterpreted, which can result in its use being unsafe. To reduce the risk of misusing or misinterpreting the 657, the user must read and understand all aspects of this Installation and Operation manual. We also suggest that the user practice all operations using the built in simulator before using the 657 at sea.
Electronic Chart: The electronic chart used by the 657 is an aid to navigation and is designed to supplement the use of official government charts not replace them. Only official government charts supplemented by notices to mariners contain the information required for safe and prudent navigation. Always supplement the information provided by the 657 with other plotting sources such as observations, depth soundings, radar and hand compass bearings. Should the information not agree then the discrepancy must be resolved before proceeding any further.
Sonar fishfinder: The accuracy of the sonar depth display can be limited by many factors, including the type of the transducers, the location of the transducers and water conditions. It is the user’s responsibility to ensure the 657 transducers are installed and used correctly.
AIS: The AIS features on this
Fuel Computer: Fuel economy can alter drastically depending on the boat loading and sea conditions. The fuel computer should not be the sole source of information concerning available fuel onboard and the electronic information should be supplemented by visual or other checks of the fuel load. This is necessary due to possible operator induced errors such as forgetting to reset the fuel used when filling the tank, running the engine with the fuel computer not switched on or other operator controlled actions that may render the device inaccurate. Always ensure that adequate fuel is carried onboard for the intended trip plus a reserve to allow for unforeseen circumstances.
Failure to adhere to these warnings may lead to death, serious injury or property damage. Northstar disclaims all liability for installation or use of this product that causes or contributes to death, injury or property damage or that violates any law.
The 657 is set up with default units of feet, °F (Fahrenheit), US gallons and knots. To change the units, see section
Northstar Explorer 657 Installation and Operation Manual | 3 |