Atal AT 505 - Fine Filter Inspection and Renewal; Oxygen Sensor Check; Technical Specification; Function Properties

Chap. I - Gas Analyser
Gas-manual-en.docx — 33 —
24.3 FINE FILTER INSPECTION AND RENEWAL
If the paper filter is contaminated it must be replaced with a new one. Its lifetime depends on the emission levels
of the vehicles tested. Where the engine is equipped with a catalyst, the life service of the filter is minimally 50
emission tests. With engines that are in a poor condition, and in the case of two-stroke engines, the life service of
the filter may only be 5 emission tests.
Filter contamination can prolong the residual hydrocarbon check and so increase the overall time of the emission
test.
24.4 OXYGEN SENSOR CHECK
Oxygen concentration measurement is done by an electro-chemical sensor with a limited service life. Service life is
affected by the composition and number of measured vehicles. The measuring optical bench checks the functioning of the
sensor automatically. If it finds the sensor is no longer in order, a warning message will be displayed and it is not possible
to continue measuring. The analyser programme displays a warning about the possible end of the sensor's service life so
that the user can contact a service technician.
The voltage status of the oxygen sensor can be displayed in the programme information (see chapter 17). A new sensor has
at least 12 mV; values below 5 mV mean the sensor is already in a poor condition and measuring is locked.
Oxygen sensor can only be replaced by an authorised service technician.
25. TECHNICAL SPECIFICATION
Quantities with accuracy figures provided are guaranteed. Other values are for information only.
25.1 FUNCTION PROPERTIES
Measurement Range Resolution Accuracy Note
CO
0
-
10 % vol
0.01
% vol
0.03 % vol or 5 % RV
CO
2
0
-
20 % vol
0.1
% vol
0.5 % vol or 5 % RV
HC
(hex)
0
-
2000 ppm vol
1
ppm vol
10 ppm vol or 5 % RV
2001
-
9000 ppm vol
10
ppm vol
or 5 % RV
O
2
0
-
4 % vol
0.01
% vol
0.1 % vol or 5 % RV
4
-
21 % vol
0.1
% vol
5 % RV
CO
cor
0
-
10 % vol
0.01
% vol
1
NO
x
0
-
5000 ppm vol
1
ppm vol
Lambda
0.500
-
2.000
0.001
ISO 3929
2
RPM
400
2001
-
-
2000 min-1
9999 min-1
10
min-1
20 min-1
2 % RV
3
Temperature
0
-
150 °C
1
°C
2°C
3
RV = of reading value
Note no.:
1 - Calculation: at CO + CO
2
≤ 15% vol CO
cor
=
2
CO + CO
CO 15
⋅
at CO + CO
2
> 15% vol CO
cor
= CO
2 - Calculation: Brettschneider´s equation **)
3 - Only for the version of analyser with built in engine speed and temperature measurement facility.