Oxygen analyzer Magnos27 Measurement principle Paramagnetic behavior of oxygen Heavy-duty thermomagnetic analyzer Sample component and measurement ranges Sample component Oxygen (O2) in flue gas or in nitrogen (N2) Smallest measurement range 0–10 vol.% O2 Measurement range quantity 2 measurement ranges Measurement range limits The measurement range is factory-set per customer order. Largest measurement range 0–100 vol.% O2 Measurement ranges within ignition limits cannot be provided. Stability Linearity deviation ≤ 2 % of span Repeatability ≤ 1 % of span Zero drift ≤ 1 % of span per week Sensitivity drift ≤ 2 % of measured value per week Output fluctuation (2 σ) ≤ 0.5 % of smallest measurement range span at electronic T90 time = 0 sec Detection limit (4 σ) ≤ 1 % of smallest measurement range span at electronic T90 time = 0 sec Influence effects Flow effect ≤ 1 % of span at a flow change of ±10 l/h. At an identical flow rate for test and sample gases the flow rate effect is automatically compensated. Associated gas effect Magnos27 calibration applies only to the sample gas shown on the identification plate (= sample component + associated gas). Temperature effect Ambient temperature in permissible range – At zero-point: ≤ 2 % of span per 10 °C – On sensitivity: ≤ 0.5 % of measured value per 10 °C relative to temperature at the time of calibration Thermostat temperature = 63 °C Air pressure effect – At zero-point: < 0.05 vol.% O2 per 1 % air pressure change – On sensitivity without pressure correction: ≤ 1.5 % of measured value per 1 % air pressure change – On sensitivity with pressure correction using integrated pressure sensor (optional): ≤ 0.25 % of measured value per 1 % air pressure change Option: Operating altitude over 2000 m Power supply effect DC 24 V ± 5 %: ≤ 0.2 % of span Position effect Approx. 3 % of smallest measurement range span per 1° deviation from horizontal orientation. Position has no effect on the hardmounted unit.
Dynamic response Warm-up time 2–4 hours 90% response time T90 = 10–22 sec, depending on sample gas flow and on measurement cell connection (see “Gas connections”, applies to an analyzer unit only with Magnos27) Calibration Zero-point calibration With oxygen-free process gas or substitute gas End-point calibration With process gas having a known oxygen concentration or with substitute gas Materials in contact with the sample medium Analyzer Rust- and acid-resistant steel 1.4580 (SAE 316Cb) and 1.4305 (SAE 303), glass Gas lines and connectors Rust- and acid-resistant steel 1.4571 (SAE 316Ti) and 1.4305 (SAE 303), PVC-C, FPM Gas connections See page 32 Sample gas inlet conditions The analyzer must not be used for measurement of flammable gases and ignitable gas/air or gas/oxygen mixtures. Temperature The sample gas dew point should be at least 5 °C below the temperature throughout the sample gas path. Otherwise a sample gas cooler or condensate trap is required. Water vapor content variations cause volume errors. Pressure The analyzer is operated under atmospheric pressure; the sample gas outlet is open to atmosphere. Internal pressure drop < 5 hPa with standard flow rate 60 l/h. Permissible absolute pressure range: 800–1250 hPa. Operation under lower absolute pressure (e.g. at altitudes above 2000 m) on request. Overpressure in the sample cell max. 100 hPa. Flow rate 20–90 l/h Note The analyzer can only be mounted in the 19-inch housing (dimensional drawing see page 32). The analyzer cannot be used in combination with the integral gas feed.
Trace oxygen analyzer ZO23 Measurement principle Potentiometric measurement; zirconium dioxide cell for determination of the oxygen concentration in accordance with Nernst’s equation; reference gas: ambient air. The analyzer is used for the continuous measurement of oxygen in pure gases (N2, CO2, Ar). The measuring cell is catalytically inactivated to the extent that flammable carrier components in stoichiometric concentrations only negligibly reduce the oxygen value. Sample component and measurement ranges Sample component Oxygen (O2) Measurement range quantity 2 measurement ranges Measurement range limits Measurement ranges are freely adjustable within the range 0–1 ppm to 0–250,000 ppm O2; they are factory-set to 0–1/0–10 ppm O2. The following measurement data refer to a measurement span of 100 ppm O2 with a regulated flow rate of 8 ± 0.2 l/h. Stability Linearity Owing to the measurement principle, zirconium dioxide cells are base linear. Repeatability < 1 % of the measurement range or 100 ppb O2 (whichever is greater) Zero drift The zero point (reference point) is displayed if ambient air is present on the sample gas side. The value for air of 20.6 % vol. of O2 (for 25 °C and 50 % relative humidity) may deviate through aging of the cell. < 1 % of the measurement range per week or 250 ppb O2 (whichever is greater) Sensitivity drift Depends on possible interfering components (catalyst poisons) in the sample gas and the aging of the cell. For pure gas measurements in N2 and Ar: < 1 % of the measurement range per week or 250 ppb O2 (whichever is greater) Output fluctuation (2 σ) < ±0.5 % of the measured value or 50 ppb O2 (whichever is greater) Influence effects Flow effect ≤ 300 ppbv O2 in the permissible range Associated gas effect Inert gases (Ar, CO2, N2) have no effect. Flammable gases (CO, H2, CH4) in stoichiometric concentrations to the oxygen content: Conversion of O2 < 20 % of the stoichiometric conversion. If higher concentrations of flammable gases are present, higher O2 conversions must be expected. The concentration of flammable gases in the sample gas must not exceed 100 ppm. Temperature effect The effect of the ambient temperature in the permissible range of +5 to +45 °C is < 2 % of the measured value or 50 ppb O2 per 10 °C change in the ambient temperature (whichever is greater). Air pressure effect No effect through a change in air pressure; the sample gas must flow out of the outlet without back pressure. Power supply effect DC 24 V ± 5 %: no effect Position effect No position effect for permanently installed instruments