Installer's handbook - 1/3 Types of installation - 2/3 Software guide ...

7. GLOSSARY OF
TERMS AND
ACRONYSM USED
IN THE HANDBOOK
Terms or Acronyms Meaning
Absolute Pressure It is the pressure measured with reference (zero value) to the perfect vacuum.
Battery Pos. (+12V Battery) It is the pole with greater electric potential of the vehicle’s battery. Normally it is
with a tension included between 8 and 16 V as to the ground.
Bottom Feed Literally supplied by the bottom. Compare with “Top Feed”. It is a particular kind of
injector, in which the fuel path only covers the lower side of the injector.
CAN Bus It is a communication system between the ECUs and the devices assembled on
the vehicle.
Catalyst It is the device assembled on the exhaust pipe that has the duty to reduce the polluting
emissions.
Changeover Switch In this handbook it is the device assembled in the passenger compartments that
enables the driver to choose the kind of feeding (gas or petrol). See also paragraph
4.9.
Configuration See “Mapping”
Connector It is the device that has the duty to connect parts of harnesses with other parts of
the harnesses or with electrical devices.
Crankshaft position (sensor) It is a sensor that is assembled near a gearwheel, integral with the driving shaft
that produces an electrical signal which represents the driving shaft position.
Cut-Off It is a particular working condition of the engine in which the injectors do not supply
fuel to the cylinders, which therefore sucks up pure air. Typically we are in cutoff
during a tip-out of the accelerator, with possible deceleration of the vehicle
(engine brake), starting from not too slow running conditions.
Diagnosis It is the identification process of a problem cause or nature, breakdown, or particular
condition or situation to be detected or signalised as malfunction.
Differential Pressure It is the difference of pressure between two areas, as for example between the airintake
manifold and the atmospheric pressure.
Duty Cycle In a rectangular waveform it is the ratio between the duration of high level and the
period of the same waveform. In formula, if Ton is the high level duration and Toff is
the low level duration, then Tp = Ton + Toff is the period and DC = Ton / Tp = Ton /
(Ton+Toff) is the Duty Cycle.
ECU (Electronic Control Unit) In this context it is the Electronic Control Unit of the engine or of the gas carburetion.
Electro-injector see Injector.
EOBD See “OBD”. European On Board Diagnostics. OBD system implementation at
European level, regularised by institutions like ISO.
Flow It is a physical quantity that defines the quantity of a fluid material that passes
through a particular section in the time unit. The mass flow defines, for example,
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