WÄRTSILÄ WARTSILA32, Руководство по эксплуатации продукта, Страница: 24 / 254

2.3.2.2 Maximum instant load steps (580 kW/cyl)
The electrical system must be designed so that tripping of breakers can be safely handled.
This requires that the engines are protected from load steps exceeding their maximum load
acceptance capability. The maximum load steps are 0-28-60-100% MCR without air assist.
Engines driving generators are prepared for air assist, see chapters Technical data and Exhaust
gas system. Sudden load steps equal to 33% MCR can be absorbed also at low load if air
assist is used. If air assist is used, the arrangement of the air supply must be approved by the
classification society.
When electrical power is restored after a black-out, consumers are reconnected in groups,
which may cause significant load steps. The engine must be allowed to recover for at least
10 seconds before applying the following load step, if the load is applied in maximum steps.
2.3.2.3 Start-up time
A diesel generator typically reaches nominal speed in about 20 seconds after the start signal.
The acceleration is limited by the speed control to minimise smoke during start-up. If requested
faster starting times can be arranged.
2.4 Operation at low load and idling
The engine can be started, stopped and operated on heavy fuel under all operating conditions.
Continuous operation on heavy fuel is preferred rather than changing over to diesel fuel at low
load operation and manoeuvring. The following recommendations apply:
Absolute idling (declutched main engine, disconnected generator)
●
Maximum 10 minutes if the engine is to be stopped after the idling. 3-5 minutes idling
before stop is recommended.
●
Maximum 6 hours if the engine is to be loaded after the idling.
Operation below 20 % load
●
Maximum 100 hours continuous operation. At intervals of 100 operating hours the engine
must be loaded to minimum 70 % of the rated output.
Operation above 20 % load
●
No restrictions.
NOTE
For operation profiles involving prolonged low load operation, please contact
Wärtsilä.
2.5 Low air temperature
In cold conditions the following minimum inlet air temperatures apply:
●
St 5ºC (when running)
●
Idling and highload - 5ºC
For lower suction air temperatures engines shall be configured for arctic operation.
For further guidelines, see chapter Combustion air system design.
2-6 Wärtsilä 32 Product Guide - a21 - 7 September 2016
Wärtsilä 32 Product Guide 2. Operating Ranges