Sun Microsystems DGA 5000, Руководство оператора

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•
The O
2
Sensor is stated by the manufacturer to have life expectancy
of 24 months from the date of manufacture, irrespective of how often
the analyser is used.
•
The (optional) NO sensor has a minimum life expectancy of 24
months after installation or until it undergoes a 20% signal strength
loss, whichever occurs sooner. It is powered by an internal battery.
The analyser must run at least 12 hours over a 30 day period to
maintain this battery at full charge.
7.2 Measurement Procedure
In order to ensure representative measurements, The engine
should be at normal operating temperature.
Note:
Under moderate loads and operating at moderate speeds a typical
nominal oil temperature is approximately 85 °C. Under these
circumstances a temperature of 65 °C is considered to be low and a
temperature of 105 °C is considered to be high. At idling speeds engine
oil temperature does not, generally, reach a nominal value. Proper oil
temperature depends on the engine operating conditions, but may be
considered acceptable if falling within the range mentioned above.
During testing, engine exhaust gas samples are continuously gathered
by means of the Exhaust Sample Probe inserted into the vehicle‟s
exhaust tail pipe.
The DGA 5000 continuously determines the amount of CO, CO
2
, HC
and O
2
present in the exhaust sample. In the Free Measuring Procedure
these values are continuously displayed in the parameter windows
together with the values for CO corrigè, engine speed and oil
temperature. If the optional NO sensor is present the value for NO will
also be measured and displayed. Depending on the selection made (see
6.5.3: „Lambda/AFR Selection‟
), the value for Lambda or Air Fuel Ratio
will also be displayed.
Besides determining whether or not the vehicle exhaust emissions
comply with legal requirements, emissions tests may be performed at
various engine speeds and under various conditions, forming a valuable
diagnostic aid in the discovery of a variety of engine, ignition and fuel
system service requirements.
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C H A P T E R 7