nCLD 844 M

Modular Gas Analyzer


  • Burners and boilers
  • Manufacturers of gas turbines
  • Certification and calibration
  • DeNOx Plants
  • Refining of fuels and lubricants
  • Tobacco industry
  • Research and development


  • Rapid system integration and rack mounting
  • Compact and modular design
  • Virtually maintenance free even in continuous operation
  • Four freely selectable measuring ranges (with dual inlet: two per channel)
  • Choice between different types and numbers of converters


0.5 ppm –500 ppm

Minimum Detectable Concentration

0.025 ppm


NO, NO2, NOx


Modular Gas Analyzer

The nCLD 844 M analyzer is the next generation in two-channel high precision nitrogen oxide measurement. Unique in speed and reliability, the nCLD 844 M is modular designed and capable of simultaneously measuring NO, NOx and NO2. The analyzers expandable capabilities allow assessment of hot and humid gas sources without additional cooler. It features a dual inlet option for evaluation of two different sources at once. The new and intuitive graphical user interface “GUI“ also individually displays and connects to other instruments’ data.

Convenient and Highly Precise
The nCLD 844 M dual channel NO, NOx and NO2 analyzer is designed for all applications with an existing gas preconditioning unit for ensuring quality control as well as keeping within threshold values. The optional hot tubing enables the instrument to directly analyze hot and moist sources without preconditioning unit and the optional electro-mechanical bypass system balances out pressure variations occurring in the sample flow. Furthermore, the analyzer is adaptable to numerous non-standardized applications. Dual sample gas inlet is an option that allows measuring two different sources simultaneously, enabling comparison. Calibration and adjustment of the unit runs quick and automatically, while all necessary data is continuously stored and available anywhere and at any time.

User Friendliness with “GUI“
The new touch sensitive graphical user interface “GUI“ enables the user to individually adjust the instrument operation and data management according to his/her needs and applications. The bright 8” monitor gives a clear overview and allows numerical and graphical display of values. Multiple digital in- and outputs guarantee a maximal connectivity for your remote operation, control and maintenance of the nCLD 844 M, ensuring unsurpassed precision and reliability.

Compact, Modular and Intelligent!
The nCLD 844 M is manufactured in a new compact and modular layout, in which each essential component of the chemiluminescence analyzer hosts its own CPU and interacts with other CPUs by BUS-communication. This assembly increases accessibility and serviceability by reducing wiring and piping. The measurement principle conforms to the standard method for NOx-detection in stationary source emissions (EN 14792).

Measuring ranges

four freely selectable ranges from 0.5 ppm –500 ppm,

with dual sample inlet: two per channel

Min. detectable concentration*

0.025 ppm

Noise at zero point (1σ)*

0.0125 ppm


<1 sec

Rise time (0-90%)

<1 sec

Temperature range

5-40 °C

Humidity tolerance

5-95% rel. h (non-condensing, ambient air and sample gas)

Sample flow rate

0.3 l/min. (1.2 l/min with pressure regulation)

Input pressure

ambient externally stabilized within ±3 mbar (600-1’200 mbar abs. with pressure regulation)

Dry air use for O3 generator

internally generated (no external supply gas required)

Power required

400 VA (incl. membrane pump and ozone scrubber)

Supply voltage

100-230 V/50-60 Hz


USB(2x), HDMI, Bluetooth, RS232 (w/o 9 pin connector), LAN, WLAN


height: 133 mm (5¼”) 

width: 450 mm (19”), with molding: 495 mm

depth: 540 mm (21.2”)


21 kg

Delivery includes

nCLD 844 M analyzer, power cable, FTDI-RS232-USB cable, USB-LAN adapter, manual


nCLD 844 M: metal converter


· hot tubing

· electro-mechanical pressure regulation

· dual channel / dual sample inlet

· dual channel NOX/NOX (with metal converter)

· USB-RS232 9pin connector

· analog output (external box): 4-20 mA into 500 Ω max.; 0-10 V





*depending on filter setting

ECO PHYSICS reserves the right to change these specifications without notice.

Further information can be found in the Product Brochure

Download Brochure


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