The laser diode gas analyzer LDS 6

The in-situ gas analyzer LDS 6 is characterized by a high availability and unique analytical selectivity and is optimally suitable for numerous applications. One or two signals from up to three measuring points are processed simultaneously by the central analyzer unit. The sensors are designed for operation under harsh environmental conditions and contain a minimum of electrical components.

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Laser diode gas analyzer

LDS 6 – new possibilities for process control and emission monitoring

The gas analyzer LDS 6 consists of a central unit and up to three in-situ sensors. The connection between the central unit and the sensors is established by a so-called hybrid cable, which contains optical fibers and copper wires. An additional cable connects the transmitter and receiver parts of the cross-duct sensor. The major part of the benefits the in-situ approach is introducing belongs to the simple fact that the measurement is performed non-intrusively and in real-time – without any disturbance or delay due to gas sampling or gas conditioning.

Wide range of applications

Besides emission monitoring there is a set of industrial applications where laser diode is already established as a standard tool for process optimization. Among the most important market segments in the process industries one will find, today: 

  • Power generation / combustion industry
    Surveillance and optimization of DeNOx plants by measuring the ammonia slip behind SCR and SNCR DeNOx installations 
  • Thermal waste treatment:
    Primary combustion control by fast measurements of the oxygen concentration and the gas temperature in furnaces and boilers.
    Surveillance and optimization of flue gas cleaning systems by measuring the waste gas concentrations before and after gas cleaning steps. 
  • Internal combustion engines:
    Measuring the ammonia slip behind DeNOx catalysts in the waste gas system of engine test beds 
  • Explosion safety:
    Immediate and 4. Intrinsically save (Ex i) concentration measurement in combustible gases like CO and CH4 or surveillance of the oxygen level in process streams, tanks or silos. 
  • Corrosion protection:
    Fast and non-intrusive surveillance of moisture in corrosive gas mixtures. 

Technical data

Max. number of components 
O2, NH3, HF, H2O, CO2, CO, HCI
Smallest measuring range 
Component-specific: 0-5 ppm bis 0-5 %

Central unit: 19“ unit

Sensors: field version

Benefits at a glance

  • Little installation effort 
  • Minimum maintenance requirements 
  • Extremely rugged design 
  • High long-term stability through built-in, maintenance-free reference gas cell, field calibration is unnecessary 
  • Real-time measurements 
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Whether you would like to know more about our In-situ analytical devices, have technical questions, or need spare parts, we have summarized essential additional information for you below.

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Well trained for excellent handling

Receive standardized or individual expertise directly from the manufacturer – with training centers in more than 60 countries.

Safety integrated

Safety is key in the process industries. A failure in instruments relevant for safety may have serious implications for humans, the process and the environment. Therefore, a wide range of our process instruments come with on-board safety features for maximum risk reduction.


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