Volvo Penta TAD734GE, Руководство по установке

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General information
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General information
EMS 2 – Engine Management System (engine control system)
EMS 2 is an electronic system with CAN communication (Controller Area Network) for controlling diesel engines.
The system has been developed by Volvo and includes fuel regulation and diagnostic functions.
The system comprises a control unit, six injectors, a number of sensors that supply the control unit with values
and connectors for diagnostics and functional checks. The engine can be connected to a communication interface
comprising a CAN link and a serial link.
CAN – Controller Area Network
The CAN link J1939 is responsible for all communica-
tion between the engine control unit (EMS 2) and a
communication interface (such as CIU/DCU) with the
exception of diagnostics. Diagnostics is handled by
the J1708/J1587 link. The CAN link is much faster
than the J1708/J1587 link and has been constructed
for connection to other components that support the
SAE J1939 protocol, such as instrument panels and
transmissions.
If a fault occurs in the CAN link, the signals from the
engine speed potentiometer and start and stop but-
tons are taken over by the J1708/J1587 link. Howev-
er, the instruments and tell-tale lamps are shut down.
If faults occur on both links, the engine will run at idle.
In such a situation, the engine can only be shut down
by using the auxiliary stop (AUX-STOP) located on
the left of the engine.
CIU (Control Interface Unit)
The CIU is a “translator” between the CAN bus and
the customer’s own control panel. The unit has two
serial communication links, a fast one and a slow one.
The fast link is the CAN link which offers a speed of
250 Kbit/s. All data concerning instruments, tell-tale
lamps, connectors and potentiometers is transferred
via this bus.
The slower link, J1708/1587 handles diagnostic infor-
mation such as flash-codes. The diagnosis tool
VODIA also uses the J1708/J1587 link to communi-
cate with the system.