NorthStar Navigation Explorer 538i - Manual (Page 33)

Northstar Explorer 538i/538 Installation and Operation Manual 33
6 The Explorer 538/538i 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.
Then press
. Wait while the Explorer
538/538i records the data.
7 The Explorer 538/538i repeats the above step
to record data up to the maximum RPM.
Then the Explorer 538/538i asks if you want
to save the curve. Select Yes. The Explorer
538/538i asks for a name for the curve.
Change the default name if required, then
press
. The new curve is stored.
Note: To interrupt making the curve at any time,
press
.
10-3 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 to be installed.
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.
2 Press one or more times until the
Setup menu is displayed, then select Fuel.
3 Select Fuel consumption curve,
then select New.
4 Enter the comfortable maximum RPM you
have measured for the engine. Do not use the
maker’s maximum RPM.
5 The Explorer 538/538i then asks you to set the
minimum RPM. Set the throttle for minimum
RPM; for a twin engine boat set both engines
to about the same minimum RPM.
Now, do not change the engine speed. Wait
for about 60 seconds for the boat to stabilise,
then press
. Wait while the Explorer
538/538i records the data.
10-3-1 Making a fuel consumption curve