27
11.6 Official test using the instrument (820 only)
Preliminary operations
• Check tightness of vehicle exhaust tail pipe.
• Disconnect any mixing devices that may dilute gases and therefore reduce the grade of
smoke.
• Insert the gas sampling probe into the exhaust tail pipe.
• Define the vehicle nominal data: fuel type, engine temperature, idle speed and maximum
rpm, emission limits (where specified).
Defining the vehicle type
In order to define the type of test to be carried out and the relative limits, the display requires
some data about the vehicle Engine Type.
Refer to the following table to select the correct item.
Limits and remarks associated with the type of
engine
If Bus K ≤ 2.6 m – 1
Otherwise K ≤ 3.0 m –1
If the vehicle is not equipped with corrector,
correct measured value
based on atmospheric pressure.
If Bus K ≤ 2.6 m – 1
Otherwise K ≤ 3.0 m –1
Acceleration after rpm stabilisation phase at half
the maximum power rpm value.
K ≤ 2.5 m –1 if the nominal value is not
present on the vehicle
ASPIRATED
WITHOUT
CORRECTOR
K ≤ 2.5 m –1 if the nominal value is not
present on the vehicle, correct the measured
value based on the atmospheric pressure
K ≤ 3.0 m –1 if the nominal value is not
present on the vehicle
K ≤ 1.5 m –1 if the nominal value is not
present on the vehicle
K ≤ 1.5 m – 1 if the nominal value is not
present on the vehicle
If the vehicle is not equipped with corrector,
correct measured value
based on the atmospheric pressure.
To Next Page
Loading...