Marine Installation Manual
2021-08
2-9
2 Engine Power and Speed
2.5 Power range limits
X72DF
The area above Lines 1 and 9 is the overload range. It is only permissible to op
-
erate engines in this range for a maximum duration of one hour during sea trials
and in the presence of an authorised engine builder representative.
The area between Lines 1, 5 and 6 (
), called ‘service range with
operational time limit’, is only applicable to transient conditions in diesel mode
(i.e. passing through a barred speed range, sea trial or emergency fast accelera
-
tion). The engine can only be operated in this area for limited periods of time, in
particular one hour per 24 hours.
