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ELECTRICAL
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Auxiliary combustion control device
The air-fuel mixture self-ignition points are mainly
influence by two factors: pressure & temperature
inside the combustion chamber. The temperature
control in all those condition in which the
combustion chamber is relatively “cold” (i.e. during
cut-off or during post-start) may improve the
reduction of ignition delay with large benefit in
terms of emission & combustion efficiency.
Auxiliary Power Management device
The total power dissipation of glow plug is not
negligible (it may vary from 240W to 750W
according with glow plug characteristics). In some
cases, it may be useful to increase the engine
load operating point in order to achieve higher
exhaust temperature (e.g. in order to start the
regeneration of diesel particulate filter). The glow
plug activation in this condition may help either
directly, increasing combustion temperature
indirectly increasing engine load as required.
The features of modern Glow plug Interface unit
must allow the EMS to operate in all of above
conditions with possibility to choose the driving
method & parameter optimization.
Command & feedback Signal Description:
Command signal:
Control unit with voltage (12V) supplies the glow
plugs. The glow plug temperature is controlled by
ECU through a function stored in memory, which
links glow plug temperature with the duration of
heat signal (12V).
Feedback Signal:
Feedback signal given by glow plug controller to
EMS ECU. Glow plug informs the EMS ECU what
the command given by ECU is followed.
Circuit Diagram:
Normal operating Mode
The diagram show the proceeding of the signals
in the function of time during the phase of pre or
post heating during normal functioning condition.
Application:
The device driven by ECU system with a
diagnosis protocol EOBD (European On Board
Diagnose) drives & checks the operating state of
each glow plug during pre & post heating phases
of diesel engine made by 3 cylinders. The
operating mode is controlled by wiring harness
through command & feedback. A protection for
high current & overload voltage is integrated & it’s
supplied by the control system.