ABB AO2000 Series, Operating Instructions Manual

Page: 350 / 362

350 AO2000 CONTINUOUS GAS ANALYZERS | OI/AO2000-EN REV. B
Limas21 HW: Operating specifications
Linearity deviation Exhaust gas and diluted exhaust gas measurement: ≤ 1 % of span, ≤ 2 % of
measured value acc. to EPA specifications for automotive exhaust gas
measurement
Process measurement: ≤ 1 % of span
Repeatability ≤ 0.25 % of span
Zero drift Exhaust gas and process measurement: ≤ 1 ppm or ≤ 1 % of span per
24 hours
Diluted exhaust gas measurement: ≤ 250 ppb or ≤ 2 % of span per 8 hours
in each case based on the smallest recommended measurement range
Daily automatic zero-point calibration recommended
Sensitivity drift ≤ 1 % of the measured value per week
Output fluctuation (2
σ
) Exhaust gas measurement: ≤ 400 ppb or ≤ 0.4 % of span at electronic T90
time = 5 s
Diluted exhaust gas measurement: NO ≤ 50 ppb or ≤ 0.5 % of span,
NO
2
≤ 60 ppb or ≤ 0.5 % of span at electronic T90 time = 15 s
Process measurement: ≤ 150 ppb or ≤ 0.15 % of span at electronic T90 time =
30 s
Detection limit (4
σ
) Exhaust gas measurement: ≤ 800 ppb or ≤ 0.8 % of span at electronic T90
time = 5 s
Diluted exhaust gas measurement: NO ≤ 100 ppb or ≤ 1 % of span,
NO
2
≤ 120 ppb or ≤ 1 % of span at electronic T90 time = 15 s
Process measurement: ≤ 300 ppb or ≤ 0.3 % of span at electronic T90 time =
30 sec
Flow influence Flow rate in the 20 to 90 l/h range: within the detection limit
Associated gas effect /
cross sensitivity
The knowledge of the sample gas composition is necessary for the analyzer
configuration. Selectivity measures to reduce associated gas effect (option-
al): Internal electronic cross-sensitivity correction or carrier gas correction
for a sample component by other sample components measured with the
Limas21 HW
Temperature influence Ambient temperature in permissible range, sample cell thermostat control to
+82 °C;
at zero point: ≤ 2 % of span per 10 °C,
on sensitivity: ≤ 2 % of measured value per 10 °C
Air pressure effect At zero point: no influence effect
On sensitivity with pressure correction with an integral pressure sen-
sor:
≤ 0.2 % of the measured value per 1 % air pressure change
The connection of the pressure sensor is led to the outside. Pressure sensor
working range: p
abs
= 600 to 1250 hPa
Power supply influence 24 V DC ± 5 %: ≤ 0.2 % of span
T
90
time T90 ≤ 5 s for measurement cell length = 260 mm and sample gas flow =
60 l/h with non-linear filter (static/dynamic) = 15/1 s.
Low-pass time constant adjustable from 0 to 30 s.