2.
General information
2.1
Explanation of symbols used
The following pictographs are used in these Operating Instruc-
tions:
i
Info
!
Attention
2.2
Application
The ETT 8.70 Exhaust-gas Analyser is used for measuring the
concentration of car exhaust emissions, either for monitoring or
engine diagnostic purposes. The unit can be used on vehicles
fitted with a 4-stroke spark-ignition and 4-stroke rotary-piston
(Wankel) engine. Measurements can only be performed on
2-stroke engines if the appropriate special accessories are used.
(see Section 3.6).
The instrument can only be operated together with a test system
(e.g. MOT 151, 250, FSA and Emission System Analysis) and it
is to this end equipped with appropriate interfaces.
If the unit is to be used for applications which require calibration,
the relevant regulations for the area/country in which it is operated
must be observed.
2.3
User groups
The ETT 8.70 has been designed for use by trained expert
personnel in the automotive industry. Read these Operating
Instructions carefully for your own safety and to prevent the unit
from being damaged through improper usage.
20
3.
Description of the unit
3.1
Functional description
The ETT 8.70 is used for measuring the exhaust-gas components
CO, HC, CO
and O
. The lambda air ratio is calculated on the
2
2
basis of the emissions values measured.
The following measurement ranges are covered:
CO
Carbon monoxide
HC
Hydrocarbons
(using hexane as a basis)
CO
Carbon dioxide
2
O
Oxygen
2
λ
Lambda air ratio
CO
vrai
The non-dispersive, infrared process is used for measuring the
CO, CO
and HC components (NDIR - non-dispersive infrared
2
spectroscopy).
The oxygen content is measured using an electrochemically
acting sensor.
The values measured are transferred via the serial interface to the
test system which then either displays or prints them out.
0 ... 10.00 % volume
0 ... 9999 ppm
0 ... 18 % volume
0 ... 21 % volume
0.500 ... 1.800
0 ... 10 %