Basler DGC-500, Инструкция по эксплуатации, Страница: 58 / 154

ECUs with an External Fuel Solenoid
The DGC-500 supports ECUs that are able to cut-off fuel from the engine without powering the ECU off.
The DGC-500 requests engine run-time every minute to keep the ECU from going into a sleep mode.
After the Pulse Cycle Timer expires, the DGC-500 checks whether ECU communication exists. If so, the
DGC-500 will not pulse the ECU. The same goes for Connecting, except that the DGC-500 remembers if
it skipped the Connecting state. If it did, then the DGC-500 will also skip the Engine Shutting Down state
when it stops the engine.
For ECUs that have an external fuel solenoid, it is recommended that the Engine Shut Down timer be set
to its minimum value. This ensures that, if the DGC-500 temporarily loses power while running, the unit
will go straight into the Run state and go to the Shutting Down state when the unit goes to Off. It is also
recommended that the Response Timeout Timer be set to its minimum value in order to set the ECU
Communications Fail pre-alarm as soon as possible.
The HMI screens shown in Figure 3-15 are displayed if the last attempt to pulse the ECU for an
information update was unsuccessful.
Figure 3-15. Screens Shown Following Unsuccessful Information Update from ECU
STATE MACHINES
A state machine is any device that stores the status of something at a given time. An input change can
change the status and/or cause an action or output to occur for any given change. A finite state machine
can be used to solve problems and describe the solution for system maintainers. State machine
illustration methods range from simple tables to graphically animated illustrations.
The following paragraphs describe how the DGC-500 functions as a state machine.
System Configuration
•
RUN, OFF and AUTO are selectable through the front panel HMI and OFF and AUTO are selectable
through BESTCOMS. However, for clarity, the term AUTO will not be used in this section. Auto-Run
and Auto-Off will be used instead. Auto-Run means the unit is in Auto while the automatic transfer
switch (ATS) is closed, or the user started the engine remotely through BESTCOMS. Auto-Off means
the unit is in Auto while the ATS is open, or the user stopped the engine remotely through
BESTCOMS. The system configuration settings for the DGC-500 are Run, Off, Auto-Run and Auto-
Off.
•
If BESTCOMS remotely started the engine before a reset occurred or the system configuration goes
to Off, then the Remote Start setting in BESTCOMS is set to Stop.
•
If ECU support is enabled when the engine is running and the system configuration goes to Off, then
the unit will go to the Shut Down state. Otherwise, it will transition to the Ready state and pulse the
ECU.
•
If ECU support is disabled and system configuration goes to Off, then the unit will always transition to
the Ready state.
Operating States
The DGC-500 supports 11 operating states. Each operating state is illustrated by a flowchart later in this
section.
•
Restart/Power-Up. The initial state.
•
Ready. The DGC-500 is in the Off or Auto-Off mode.
•
Pulsing. ECU Only—pulses (momentarily powers up) the ECU for updated information.
•
Connecting. ECU Only—the system configuration just changed to Run or Auto-Run.
•
Pre-Start. Closes the pre-start relay or pauses the DGC-500 while it is not safe to crank.
3-28 DGC-500 Functional Description 9355400990 Rev H