Principle Of Operation - AEB Leonardo 175 Mode D'emploi Et Garantie

Principle Of Operation

The "Leonardo" is a micro - processor controlled system for the management of carburetion on
alternative fuel powered vehicles. It is programmable, it's an adaptive learn system managed by microprocessor,
and able to maintain stoichiometric ratio between air and alternative fuel (C.N.G. or L.P.G.) under any operational
condition by utilizing the following inputs:
• LAMBDA SENSOR
• RPM
• THROTTLE POSITION SENSOR (T.P.S.)
The signal of the above sensors is different according to the vehicle model. Moreover, the operational
characteristics are also different according to the vehicle. To correctly manage these signals, the "Leonardo"
requires programming that can be achieved by means of one of the following devices.
• PERSONAL COMPUTER on which a specific SOFTWARE program (Code AEB004) is installed,
communicating with the "Leonardo" through SERIAL INTERFACE (Code AEB001)
• HAND - HELD TESTER
The "Leonardo" also makes it possible to simulate the correct operation of the Lambda sensor during alternative
fuel operation without the aid of external simulators.
The alternative fuel modulation is achieved by means of an electro - mechanical actuator installed in the
vapour hose connecting the pressure regulator to the mixer.
The electro - mechanical actuator consists of a plastic body provided with a calibrated orifice through
which the alternative fuel transits. A stepper motor is mounted on the plastic body. The stepper motor modulates
the amount of alternative fuel according to the engine needs. Since the "Leonardo" is an adaptive learn system,
it does not require periodic adjustments. The only manual adjustment to be performed is the idle mixture on the
pressure regulator. It is important that this adjustment is performed with great precision. Although the "Leonardo"
is capable of modulating carburetion at idle, this modulation is not optimized if the manual adjustment is poorly
performed, as the modulating ability of the "Leonardo" is limited at idle, and only indicated for fine adjustments.
The "Leonardo" ECU manages the operation of the alternative fuel electrovalves directly. The switch
provided is used only to select the fuel used.
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English
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