Manual Operability Or Emergency Control; Indication Of Cruising State - Aventics Marex OS II Bedienungsanleitung

4.5.3

Manual operability or emergency control

According to the instructions of the classification societies there must always be a second possibility to control the engine
and gear beside the remote control. In case of a remote control failure this second controllability must work without
restrictions.
Often there are switches in the engine room to adjust the gear position or as well the engine speed independently from
the remote control. This manual operability is connected directly with the propulsion in case of many systems, i.e. gear
shifting is effected directly at the gearbox, whereas the engine speed is adjusted directly at the engine.
Beside the direct adjustability, a line of communication must be provided between the active control station and the
engine room, via which the steersman can transfer the cruising commands in case of a remote control failure. For larger
vessels this line of communication is realized by a so-called ship telegraph. An alternative is a direct communication via
phone or walkie-talkies.
If a manual operability and a line of communication between steersman and engine operator are not existent, an
emergency control independent from the remote control must be provided at the control station. The emergency control
is not part of the Marex OS II remote control, as the emergency control must be independent from the remote control.
In this connection twin- or multiple-engine systems represent a particularity. All equipment to operate a propulsion
system (remote control, safety system) should for multiple-engine systems are provided separately for each system, i.e.
if a component of one propulsion system fails, this must not have any effects on the other propulsion system. To what
extent a second possibility to control every single system could be abandoned, has not been clearly defined by the
classification societies and depends on the respective individual case. As in case of a failure of one propulsion system
the vessel can still be controlled via the remaining propulsion system, an additional control facility beside the remote
control might be abandoned.
4.5.4

Indication of cruising state

According to the instructions of the classification societies, the cruising state of the propulsion system (rpm and position
of the gear ahead, neutral or astern) must be indicated at each control station. Here, usually the actual state of the
propulsion system is to be indicated, not the set point of the remote control.
The engine speed is usually indicated by the engine safety system on a speed measuring instrument. The gear direction
can be signaled independently from the remote control via additional lamps at the control station, which are directly
connected to the gear.
An indication of the engine speed or the gear position by additional displays or lamps of the Marex OS II remote control
is permissible. For this, the Marex OS II remote control is equipped with additional modules, as a bargraph to indicate the
engine speed or modules with additional lamps to indicate the gear position. These modules, however, are not included
in the standard version of the Marex OS II remote control.
The shipbuilder is responsible for the implementation of the indication of engine speed and gear position. For this reason
this indication is described by the shipbuilder.