NDIR - gas analyzer for CEMS


This all-in-one solution represents a compact and cost efficient gas analyzing system for Continuous Emission Monitoring (CEMS). It can be used for various operation units to monitor the emission limits required by authorities and to optimize process parameters.

CEMS-in-a-box includes a high precision NDIR analyzer, which operates in change-flow-mode (CFM) to ensure a stable zero point. Furthermore, this system includes an electric gas cooler, an autocalibration unit, a purge unit, a HMI and various I/O functions.

Measurement principle:

SO2, NOX, CO and CO2 are measured by a nondispersive infrared (NDIR) analyzer. As sample gas enters the analyzer, it gets filtered and precisely cooled down to 4°C, which minimizes humidity influences. Additional pressure regulation as well as temperature regulation allow measurements with highest accuracy. A Control Valve Unit enables a change-flow-mode technique to ensure a long-term stability.

Furthermore, an O2-sensor, a purge unit, a housing cooler and an autocalibration unit can be integrated if necessary.

cems continous emission monitoring
size: 687 x 860 x 360 mm

Flow Diagram

flowdiagram cems-in-a-box
  1. Key Features
    • Simultaneous measurement of CO, NOX, SO2, CO2 and O2
    • For boilers, furnaces, rotary kilns, SRU´s, coke ovens and others
    • Integrated gas pretreatment system
    • Long-term stability by NDIR operating in CFM
    • Installation close to stack/boiler
  2. Main Features
    • Suitable for a variety of applications due to different measurement ranges.
    • An integrated housing cooler unit ensures a stable air conditioning inside the box.
    • Includes compact gas cooler, pumps, filters, valves
    • Change-flow-mode: The Control Valve Unit is managing the automated
      Zerogas and Spangas calibration, the purging function and ensures a stable pressure regulation.
    • An integrated HMI is managing the analog and digital communication as well as the 7" Touch- Panel for operation purposes.
  3. Measuring Range

     max. rangemin. rangeoptional
    Measuring range
    SO20 - 5.000 ppm0 - 250 ppm0 - 50 ppm
    NO0 - 5.000 ppm0 - 450 ppm0 - 100 ppm
    CO0 - 5.000 ppm0 - 200 ppm0 - 100 ppm
    CO20 - 20%
    O20 - 25%

  4. Specifications

    Linearity≤ ± 1% of full scale
    Zero drift≤± 1% of full scale per week
    Span drift≤± 1% of full scale per week
    Repeatability≤± 0,5% of full scale
    Response time< 180 s
    Ambient conditionsTemperature: -5 to 35 ̊C (50 ̊C optional), Humidity: < 90%, shelter or roof required, no direct sun exposure
    Sample gaspre-conditioning required, heated sample line, filtered
    Gas flow3 l/min (1), warning message for incorrect flow values
    Power supply90 - 264 V AC/50 - 60 Hz, internal safety management, max. power consumption 380 W
    Dimensions860 x 687 x 360 mm
    AssemblyOutdoor wall installation under shelter or installation in control room
    Analog outputCurrent output 4 - 20 mA for each measured gas
    Analog inputExternal sensors (e.g. H2O, pressure) can be connected
    Digital outputAnalyzer status, warnings, purging
    Digital inputRemote calibrations
    CommunicationModbus TCP/IP
    Weight40 kg
    Gas connections1 x zero gas, 5 x span gas, sample gas, exhaust, drain, compressed air
    Zero point correctionAutomatically done by change-flow-mode
    InterfaceIntegrated HMI with 7" LCD (capacitive touch)
    OptionsProbe purging unit, autocalibration unit, O2- sensor, housing cooler
    1 can be adjusted if necessary

  5. Download

    Broschure 2020



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