AVL Opacimeter

State-of-the-art emission measurement

Your instrument for the continuous measurement of exhaust gas opacity

AVL Opacimeter

The AVL Opacimeter is a highly dynamic partial-flow measuring instrument for the continuous measurement of exhaust gas opacity (in particular from diesel engines).
It can be used during stationary and transient engine operation and is therefore perfectly suited for R & D, certification purposes and for production conformity tests. 

Recent emissions legislation has tightened the requirements for transient test procedures. To pass future emissions limits, it will also be necessary to monitor the engine’s particulate emissions during transient operation, even in the early stages of an engine R & D process. 
Therefore, an instrument with a very fast response time combined with a high accuracy is required. 

Measurements in front of an engine aftertreatment system, where high exhaust pressures and temperatures are present, must also be possible, e.g. upstream of a diesel particulate filter (DPF).


An Innovative and Efficient Solution

This innovative tool measures the loss of light intensity between a light source and a receiver and makes it easy to calculate the opacity N [%] and the light absorption coefficient k [m-1]. In addition to its super-fast response time of 0.1 seconds, the AVL Opacimeter can also make measurements upstream and downstream of the DPF. This makes it a valuable tool in your testing environment.

Technical Data  

Measurement principle

Light extinction
Measurement value output  Opacity N [%],
Light absorption coefficient k [m-1]
Measurement range N = 0 to 100 %,
k = 0 to 10 m-1
Measurement value resolution

0.01 % or 0.001 m-1


Opacimeter 3 lowres
Transient Testing

Highest measurement dynamics for transient test runs.

Signal Stability

High measurement value resolution and signal stability thanks to the conditioning of all essential parts. 

Compliance with Regulations

The opacimeter complies with all technical requirements for emission certification testing. 

Compliance with Technical Requirements and Regulations

Our opacimeter complies with all legal requirements for emission certification testing. It meets standards including:

  • ECE R24
  • 72/306/EEC, 77/537/EEC
  • ELR test cycle for
    • Euro III according 1999/96/EC 
    • Euro IV and Euro V according 2005/55/EC and 2005/78/EC
  • GB 3847-2018
  • ISO 8178-9
  • ISO 11614 
  • SAE J 1667

High Pressure Option

The growing trend towards developing engines with different exhaust aftertreatment systems requires special application components for particle measurement instruments. AVL Opacimeters include a high-pressure option, which extends the scope of application, enabling opacity measurements to be made using standard equipment with exhaust gas pressure peaks up to 3,000 mbar (relative to ambient pressure) and exhaust gas temperatures up to 800 °C.

Customer Services
Customer Services for Testing Solutions

The AVL Customer Services organization consists of more than 700 service- and application engineers worldwide, operating from more than 50 locations. Our global footprint is your local benefit.

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