AVL AVL DiCom 4000, Service Manual

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4000 Evaluation Unit
Service Manual 4-61
Valve voltage, setting
The various valve positions can be set with the
VALVE
button (calibration, measurement,
closed) – the corresponding valve voltage is displayed.
•
Check the valve positions. The offset of the valve vane from the inlet or outlet
aperture should not be more than ±2 mm.
−
When adjusting the valve, make sure that it runs quietly and smoothly.
−
Any irregular noises (such as noticeably getting louder and quieter) suggests a
fault or heavy soiling of the valve.
Temperature
Measuring chamber temperature
The measuring chamber temperature is displayed.
−
You can observe the heating process and control behaviour.
−
If 100° C is not reached, the heating element may be defective.
−
Once the heating system has stabilised (after approx. 15 min), the measuring
chamber temperature should be 100 ± 10° C.
Inlet temperature
Displays the exhaust gas temperature (PT 100 at exhaust inlet to opacity measuring
chamber)
Measuring head
Displays the selenium board temperature.
The temperature should be the same as the ambient temperature or slightly higher.
System
Inside temperature of instrument
Linearity
•
Carry out a linearity test by pressing
LIN
.