Sices HS 315, Technical Handbook

Page: 172 / 255

154 Technical Handbook
The ECU_ENABLE control should be used to give a consent to the starting of electronic control
units of the engines. Lacking this consent, it is reflected in the shutdown of the fuel injection
system: therefore, without this consent then the engine cannot start, but instead it will be
stopped if it was running.
If ECU_ENABLE (not present) or STOP (present) controls are used to stop the engine, but a
solenoid valve is anyway present on the fuel line, it is possible that the vacuum in the fuel
circuit caused by the engine that is stopping may prevent the correct movement of the solenoid
valve. In these cases, by using P.0234 parameter, it is possible to delay the closing control of
the fuel solenoid valve with reference to the stop control (ECU_ENABLE or STOP) of the
engine: the engine is stopped through its own stopping system and, when the engine is
stopped, the fuel solenoid valve can be closed.
This control should be used for the direct control of the starter motor. The board enables the
START output to start the engine and shall remove it immediately when it detects a "started
engine" status (see 9.7.5). In this way, it ensures the immediate release of the starter motor
ring gear, therefore avoiding that the starter motor is dragged by the engine. In case of failure
to start, the board deactivates the START output at the end of the starting attempt.
The duration of each starting attempt is automatically determined by the P.0210 parameter
("Duration of the starting control"). This duration may be increased for gas engines (see
below).
The cycle duration of the manual start depends on bit 1 of parameter P.0495:

0: the duration of the start attempt is established by the operator; the attempt interrupts
when the operator releases the START button.

1: the duration of the start attempt is selected by parameter P.0210.
For start cycles controlled through the serial port, the instructions for the automatic are valid.
This control only makes sense for GAS engines. The aim is to perform the washing cycle of
the engine. When a GAS engine is turned off, in the feeding circuit unburned gas is still
present. If it is not disposed of before the next starting, it could be dangerous because it could
explode unrestrainedly. Therefore, each time the engine is started, the washing cycle to
remove this unburned gas is performed. The cycle consists in making the engine run, through
the starting motor, without opening the GAS valve: the vacuum caused by the engine is enough
to remove the unburned gas.
This function is enabled by setting P.0241 parameter to a value higher than zero. The GAS
solenoid valve is opened after P.0241 seconds from the time the starter motor was activated
(START): for this reason, if the duration of the starting cycle (P.0210) is lower than P.0241
parameter, it is automatically lengthened to a second more than P.0241.
If the starting attempt ends without that the engine has started, the board closes the GAS
valve, and, at the next starting attempt, the washing cycle will be repeated.
This control is used in systems where it is preferred to give priority to the supply by the
generator. When the FUEL control is used, as a matter of fact, a failure of the solenoid valve
control system results in its closure, and the resultant stop of engine consequently.
The STOP control is instead active only during the stopping cycle. Its purpose is to block the
flow of fuel to the engine only during the stopping phase: when the engine has been stopped,
the output is disabled, so allowing the reopening of the fuel pipeline. In this case, it is always
possible to start the engine, even at the presence of a fault on the STOP control: at the limit it
will not be possible to stop the engine.