How it works
The ICAD (Iterative Cavity enhanced DOAS) NO₂ (Nitrogen Dioxide) / NOx (Nitrogen Oxides) / NO (Nitric Oxide) measurement system leverages advanced optical absorption spectroscopy and patented ICAD technology, providing high levels of sensitivity and accuracy, ensuring interference-free measurements for precise data analysis. This measurement system gives you reliable insights into levels of NO, NOx, and NO₂.
The “L” series features an enhanced sensitivity by using a longer absorption cell and increased reflectivity mirrors than the ICAD 200. By measuring the absorption spectrum and applying the ICAD algorithm, the unique and characteristic absorption structure of NO₂ is directly identified and separated from other overlapping absorptions like water vapour (H₂O) or Glyoxal (C₂H₂O₂). This gives the advantage of direct NO₂ measurements (in comparison to CLD) without interferences to other substances or the need of drying mechanism which introduce new interferences (e.g., CLD, CRD, CAPS).
This NO / NOx / NO₂ measurement system has no absolute zero-point drift as it relies on characteristic differential absorption structures, rather than absolute intensities. It also means that it is insensitive to temperature variations, vibrations, and light source degradation, setting it apart from other optical instruments.
The ICAD system has an internal converter for NO to NO₂ (optional) with a NOx free O₃ source allows measuring also NOx/NO with the same system (patented).
No consumable gases are required making the operation simple. Data display is directly available with any WiFi or LAN device or over the RS232 interface
Other High Grade ICAD Monitors include:
ICAD NO₂ 200L Monitor
ICAD HONO / NO₂ 200L
Servicing
Contact us for servicing information.
Datasheet
NO₂ NOx NO Analyser Series 200 High Grade Version
Specifications
- Measurement range*1: 0 – 2000 ppb
- Power consumption: Less than 30 W at 12 V (typ.)
- Time resolution: 2s to 60s (1s with post-processing possible)
- Dimensions: 19” Rack housing 13.2 x 43.8 x 61 cm
- Limit of Detection: (at 2 s) *1 0.2 ppb, 12 ppt at 1800 s
- Start-up time: Less than 1 min (typ.)
- Precision: (1σ at 2 s): 0.1 ppb or 2%
- Temp. range of operation: -10 to +25°C (+40°C with cooling option)
- Detection of NO₂: Direct spectroscopic measurement
- Temperature sensitivity: Less than 0.01 ppb/°C
- Detection of NOx / NO: By conversion to NO₂
- Cross sensitivity: No significant cross sensitivity*5
- Response Time: (10% to 90%)*2 2s at 1 l/min or 1s at 2 l/min
- Weight: Less than 11.7 kg (depending on config)
- Zero Drift: Less than 0.1 ppb/month*3
- Consumable gases: No gases needed for operation
- Sample flow: 1 to 2.5 l/min
- Other detectable gases: Glyoxal, CO₂ (optional NDIR sensor)
- Calibration: NO₂ calibration gas not needed*4; NO gas for converter calibration (only for high NOx measurements)
- Data communication: LAN/WiFi/RS232/M2M/OPCUA;BayernHessen Protocol; Voltage/Current Output (on request)
- Path length characterisation: Helium gas (1 to 2 years interval)
- Processing unit: Internal embedded PC, with data analysis and measurement software
- Mechanical stability: Insensitive to vibrations
*1 Custom specifications with different measurement range are possible. By reducing the measurement range better precision and LOD can be achieved.
*2 Response: Different measurement cell types are available, allowing different response times. Smaller measurement cells allow a much faster response time, but result typically in a lower precision.
*3 Upper limit. Drift is negligible due to regularly automated reference measurements. *4 Literature absorption data for NOx is used for gas quantification.
*5 No significant spectroscopic cross sensitivity with respect to: Carbon oxides, Methane, H2CO, Hydrogen, Sulphide, Sulphur Dioxide, Chlorine, Chlorine Dioxide, Hydrogen Cyanide, Hydrogen Chloride, Phosphine, Hydrogen, Ammonia, Acetylene, Nitromethane, Ethylene, Ethanol, Methyl Mercaptan, Ethyl Mercaptan
