Wartsila 31, Product Manual

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In isochronous mode the speed reference remains constant regardless of load level. Both
isochronous load sharing and traditional speed droop are standard features in the speed
control and either mode can be easily selected. If the ship has several switchboard sections
with tie breakers between the different sections, then the status of each tie breaker is required
for control of the load sharing in isochronous mode.
13.3 Alarm and monitoring signals
Regarding sensors on the engine, please see the internal P&I diagrams in this product guide.
The actual configuration of signals and the alarm levels are found in the project specific
documentation supplied for all contracted projects.
13.4 Electrical consumers
13.4.1 Motor starters and operation of electrically driven pumps
Motor starters are not part of the control system supplied with the engine, but available as
loose supplied items.
13.4.1.1 Engine turning device (9N15)
The crankshaft can be slowly rotated with the turning device for maintenance purposes and
for engine slowturning. The engine turning device is controlled with an electric motor via a
frequency converter. The frequency converter is to be mounted on the external system. The
electric motor ratings are listed in the table below.
Table 13-2 Electric motor ratings for engine turning device
Current [A] Power [kW] Frequency [Hz] Voltage [V] Engine type
10 - 6A 4.0 50 / 60 3 x 400 - 690V Wärtsilä 31
13.4.1.2 Pre-lubricating oil pump
The pre-lubricating oil pump must always be running when the engine is stopped. The engine
control system handles start/stop of the pump automatically via a motor starter.
It is recommended to arrange a back-up power supply from an emergency power source.
Diesel generators serving as the main source of electrical power must be able to resume their
operation in a black out situation by means of stored energy. Depending on system design
and classification regulations, it may be permissible to use the emergency generator.
Electric motor ratings are listed in the table below.
Table 13-3 Electric motor ratings for pre-lubricating pump
Current [A] Power [kW] Frequency [Hz] Voltage [V] Engine type
28.4 15.0 50 3 x 400
W31
25.7 15.0 60 3 x 440
13.4.1.3 Stand-by pump, lubricating oil (if applicable) (2P04)
The engine control system starts the pump automatically via a motor starter, if the lubricating
oil pressure drops below a preset level when the engine is running.
Wärtsilä 31 Product Guide - a1 - 18 October 2016 13-7
13. Automation System Wärtsilä 31 Product Guide