Delphi Multec 3.5, Руководство по применению

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Product Description Multec 3.5 Fuel Injector Application Manual
3-38 Delphi Energy and Chassis Systems
Revision: 11/05-1
3.14
Noise
Injector noise is generated by valve impact when opening and closing on
the seat and pole piece stop. Injector noise is perceived as a “ticking”
sound. See Figure 3-5
Other engine noise is often attributed to the injector (valve train noise and
the fuel line ‘hammer’ noise generated by the injector on/off fuel flow
interruptions interacting with the fuel rail and fuel lines). Proper hydraulic
damping of the fuel system is recommended to prevent the propagation of
fuel flow induced noise.
Refer to Section 5.2.1.4 A sequential firing scheme will generally reduce injector noise. Injector
noise can also be reduced by improving injector noise absorption (i.e., an
engine cover).
3.15
Electrical Specifications
3.15.1 Solenoid Coil Specifications
Solenoid electrical specifications for the Multec 3.5 Fuel Injector are
presented in Table 3-1.
3.15.2 Avalanche Energy
Avalanche Energy supplements inductance as a solenoid specification
parameter relevant to injector driver requirements. Avalanche Energy is
the inductive energy stored in the magnetic field of the solenoid that is
released back into the driver circuit when voltage is switched off.
Current in the injector coil generates a magnetic field when the injector is
energized. This field breaks down as the current decays when the injector
is turned off inducing a voltage spike in the injector coil (much like an
ignition coil). However, instead of generating a spark, the voltage spike
known as “flyback voltage” is limited by the Zener diode avalanche
voltage in the injector driver. (See section 4.4.5.1.)
Energy from the magnetic field measured as avalanche energy must be
dissipated in the engine controller. The engine controller must be
configured to absorb or dissipate appropriate amounts of avalanche
energy.
∫
=
t
Zener
V I Energy Avalanche *