IMR - Model ET 101 -Opacity Monitor

The ET101/102 Opacity Monitor is a single-pass transmissometer consisting of visible light transmitter and receiver arrangement with digital data processing in a local display unit. The monitors can display data in opacity, extinction or dust density in mg/m3 or normalized dust density in mg/Nm3.

Using analog inputs from a process, the ET102 offers normalization of the opacity data from temperature, oxygen, pressure and water vapor.

• Simple instillation for low initial cost
• Proven technology offers low maintenance and high reliability
• High-efficiency air purges minimize lens contamination
• Data in percentage opacity, mg/m3, mg/Nm3 dust for optimum flexibility

Operating Principle

• Single pass transmissometer

Light Source 

• Modulated high-intensity LED at 637 nm wavelength

Span

• Fully selectable in % opacity, extinction, mg/m3 & mg/Nm3

Averaging 

• 4 rolling averages selectable from 10 secs to 30 days

Accuracy

• ±0.2% opacity

Drift 

• <1% opacity per month

Resolution

• 0.1% opacity

Optical Path Length 

• 1.6 feet – 49 feet