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3.2 Technical operation
3.2.1 engine Starting Sequence
The PowerWizard receives an engine start signal. The signal will be one of three.
1.
The operator presses the Run key
•
The control is in auto and the remote initiate digital input becomes active
•
The control receives a start command via the RS-485 SCADA Data Link (PowerWizard 2.1 only)
•
The control has a program cycle timer (PCT) configured that becomes active (PowerWizard 2.1 only).
•
The PowerWizard checks the system before beginning the cranking sequence. The PowerWizard checks that there are no
2.
shutdown events present and that all previous shutdown events have been reset.
If the engine is equipped with a form of start aid such as thermostart it will enter a prestart sequence.
3.
The PowerWizard begins the crank sequence by activating the engine crank relay and the fuel control relay.
4.
If the engine reaches the setpoint for crank terminate speed the engine is deemed running and the engine crank relay will
•
be deactivated
If the engine fails to start within a preset duration (normally seven seconds) the PowerWizard will stop cranking and wait
•
for a preset time (normally seven seconds) before attempting to start again
If the PowerWizard fails to start within a preset number of crank attempts (normally three) the PowerWizard will activate a
•
“Fail to Start shutdown”.
3.2.2 engine Stopping Sequence
The PowerWizard receives an engine stop signal. The signal will be one of four.
1.
The operator presses the stop Key
•
The control is in auto and the remote initiate digital input becomes inactive
•
The control receives a stop command via the RS-485 SCADA Data Link (PowerWizard 2.1)
•
The control has a program cycle timer (PCT) configured that becomes inactive (PowerWizard 2.1 only)
•
The PowerWizard begins the cooldown period. In order to bypass the cooldown hold down the Stop key for 3 seconds. The
2.
options “PRESS ENTER TO BYPASS” and “PRESS ESCAPE TO CONTINUE” will be shown on the display. Press the Enter key to bypass
the cooldown sequence or press the Escape key to continue the cooldown sequence.
After the cooldown cycle, the PowerWizard stops the engine by turning off the fuel control relay.
3.
3.2.3 event System
The PowerWizard module uses the J1939 standard format for events, whereby an event is defined as a combination of a suspect
parameter number (SPN) and a failure mode identifier (FMI). The SPN defines what is at fault and the FMI defines how it is at fault
(e.g. SPN = 100 = Oil Pressure, FMI = 1 = Low Shutdown would mean the generating set has shutdown on a low oil pressure fault).
A list of SPN / FMI combinations can be found in appendix A.
PowerWizard modules have separate event logs for events raised by the module itself and those raised by ancillaries such as the
engine ECM.
3.2.4 event State
Events in PowerWizard may exist in one of three states, present, active and inactive.
Present
– The condition causing the event is ongoing and affecting system behavior. If an event is present it cannot be reset.
active
– The event is no longer present and can be reset by the user. However it has been latched by the event system and needs
to be reset before the engine can be restarted.
Inactive
– The event was active at some time but is no longer active and is not affecting system behaviour. Inactive events exist
for historical purposes only.
