Laser Diode Gas Analyzer

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.

Process analytics goe in-situ - Laser Diode Spectrometer LDS 6

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Laser diode gas analyzer

LDS 6 – new possibilities for process control and emission monitoring

The compact Laser Diode Spectrometer LDS 6 for process control even under extreme measuring conditions. Remote sensing without cross interferences and innovative laser technology.

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. 
Get an overview of our process analytics portfolio

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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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Information at a glance

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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Proposed solutions for your queries and direct access to our experts in Technical Support.


Service offers

To remain competitive, companies in industry must ensure – and ideally increase – the availability and productivity of machines and plants. As your partner, we offer a unique range of services and support based on our extensive technology and industry expertise.

Service catalog

As your partner, we offer a unique range of services and support based on our extensive technology and industry expertise. With our offerings, you can expect a high degree of reliability and a successful digital future for your company.


Well trained for excellent handling

Siemens experts are available with a variety of training courses and to help you understand gas chromatography and continuous gas analysis and how to operate and maintain your Siemens analytical products. Siemens offers both introductory and advanced courses several times a year.


How can we help you?

We are represented worldwide with production facilities and system integration centers. Each center, whether in Houston, Singapore, or Karlsruhe, has its own sales, engineering and assembly teams, service and logistics hotlines and well-equipped training centers. In addition, our employees have a global presence and are familiar with all relevant local requirements, guidelines, and standards.

Customer Support: 1-800-448-8224

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