WÄRTSILÄ 46DF, Product Manual

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Fig 14-4 Operating modes are load dependent
14.2.3.3 Points for consideration when selecting fuels
When selecting the fuel operating mode for the engine, or before transferring between operating
modes, the operator should consider the following:
●
To prevent an overload of the gas supply system, transfer one engine at a time to gas
operating mode
●
Before a transfer command to gas operating mode is given to an engine, the PMS or
operator must ensure that the other engines have enough ‘spinning reserve’ during the
transfers. This because the engine may need to be unloaded below the upper transfer limit
before transferring
●
If engine load is within the transfer window, the engine will be able to switch fuels without
unloading
●
Whilst an engine is transferring, the starting and stopping of heavy electric consumers
should be avoided
14.2.4 Stop, shutdown and emergency stop
14.2.4.1 Stop mode
Before stopping the engine, the control system shall first unload the engine slowly (if the engine
is loaded), and after that open the generator breaker and send a stop signal to the engine.
Immediately after the engine stop signal is activated in gas operating mode, the GVU performs
gas shut-off and ventilation. The pilot injection is active during the first part of the deceleration
in order to ensure that all gas remaining in engine is burned.
In case the engine has been running on gas within two minutes prior to the stop the exhaust
gas system is ventilated to discharge any unburned gas.
14.2.4.2 Shutdown mode
Shutdown mode is initiated automatically as a response to measurement signals.
In shutdown mode the clutch/generator breaker is opened immediately without unloading.
The actions following a shutdown are similar to normal engine stop.
Shutdown mode must be reset by the operator and the reason for shutdown must be
investigated and corrected before re-start.
14-6 DBAD209883
Wärtsilä 46DF Product Guide 14. Automation System