User manual NAVMAN 8120

[. . . ] Datahelm 8120 Installation and Operation Manual www. navman. com Contents 1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1-1 Overview . 7 1-4 Removing and replacing the display unit . 8 2 Basic Operation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2-1 Using the keys . 10 2-2 Turning on and off / auto power . [. . . ] Remaining The amount of fuel remaining in the tank. For twin engine installations, the fuel flow for each engine is shown separately. This is useful for checking that both engines are under the same load. Speed If the Instrument has both GPS and paddlewheel speed available then you can select which to use. The choice affects the calculated Range and Economy (see section 17-5 Speed source). If the Instrument uses a paddlewheel sensor to measure speed, then the speed must be accurately calibrated (to calibrate the Instrument paddlewheel, see section 17-11). Consumption The fuel used per unit of distance travelled. The smaller this number, the better the fuel economy. Adjust the throttle and trim to achieve the lowest consumption. Economy Economy is the distance travelled per unit of fuel used. The Instrument calculates this from the boat speed and fuel used. The bigger this number, the better the fuel economy Range The estimated boat range at the current fuel flow. 47 8120 Installation and Operation Manual 13-3 Fuel consumption curves A fuel consumption curve is a powerful tool for assessing your boat performance in different conditions and for helping you to run at the most economical speed for the conditions. Fuel consumption curves require engine RPM, which requires SmartCraft or diesel sensors to be installed. 13-3-1 Making a fuel consumption curve Making a fuel consumption curve requires running the boat in a straight line through the engine's full RPM range for about 15 minutes. For your first curve, choose a calm day with light wind and little current; have a typical load and a freshly cleaned hull. Then you can make fuel consumption curves for different boat, weather or sea conditions. Compare these with your first curve to see how your boat's performance changes with conditions. Making a curve 1 Start running the boat in a straight line. 3 Select Fuel consumption curve, then select New. 6 The Instrument then asks you to set the throttle to achieve a target RPM. For a twin engine boat set both engines to about the target RPM. When the engine RPMs are correct, the Target RPM box will turn green. Now, do not change the engine speed. Wait for about 60 seconds for the boat to stabilise, ensuring the Target RPM box stays green. Wait while the Instrument records the data. [. . . ] The distance from the plotted course to a CDI line is the CDI scale. Set the CDI scale (see section 17-2) to the maximum distance that the boat should deviate from the plotted course. The chart and highway windows show the CDI lines, which are like a highway over the water where the boat will move. The windows show how far the boat has deviated from the plotted course and if the boat is approaching a CDI line. [. . . ]