To determine the waiting time for reversing the control
calculates the current ship speed from the lever position.
If the lever of the control head is moved from ahead to
astern, the engine speed will be reduced to idle speed.
But the gear is not yet disengaged.
To avoid engine stalling during a reversal, the reversing
procedure can only be carried out below a maximum ship
velocity for reversal. If the vessel is faster than the
maximum velocity, it must be held off on the reversing
until the vessel has lost speed. The engaged propeller
drags the engine actuated with idle speed and acts as a
brake in this conjunction.
When the calculated ship speed is below the maximum
velocity for reversal, the gear is disengaged.
Subsequently, the engine speed is increased to a clutch engagement speed calculated before. Depending on the ship
velocity the calculated clutch engagement speed can lie between idle speed and the maximally possible engine speed
for clutch engagement indicated by the gear manufacturer. After expiration of a waiting time the gear is engaged in
contrary direction. Afterwards, the control waits for a short time again until the engine speed is increased to the set speed
given by the control head lever.
The waiting times can be so short that they are not recognized by the steersman. They are optimized during the
commissioning of the remote control. The calculation of the ship speed and the maximum velocity for reversing are
optimized during the commissioning of the remote control as well.
The Marex OS II control is thus able to make sure that the engine is not stalled, independent of the target according to
the lever position set by the steersman, and therefore to realize the shortest distance for stopping.
waiting time
after clutch
engagement
waiting time before
clutch engagement
set engine speed
gear
time
time
acceleration curve
time
maximum velocity
for reversing
ahead
astern
idle
calculated
ship velocity
calculated clutch
engagement speed
ahead
astern
waiting time
after clutch
engagement
waiting time before
clutch engagement
set engine speed
gear
time
time
acceleration curve
time
maximum velocity
for reversing
ahead
astern
idle
calculated
ship velocity
calculated clutch
engagement speed
ahead
astern
