Back Scattered Dust Monitor

Veritcal View
Model VBDM-150
Digital Ouput RS 485
Certification TUV
Accuracy -/+2 %
Response Time Less than 10 seconds
Display TFT Touch display
Operating Power 230 VAC, 50 Hz
Analog output 4-20mA
Power Supply 230 V AC, 50 Hz
Reslution 1 mg /Nm3
Linearity +/- 1 %
Auto cleaning Facility Yes using moisture free instrument air or compressed air
Calibration Performance SPAN & ZERO check facility available
Measuring Range 0-100, 0-500 , 0-100 mg/Nm3
Relay Outputs 1 NO, 1 NC available
CPCB Online Connectivity Yes Cloud base Server to CPCB &SPCB
Data Storage capability Up to 2 years inbuilt data storage facility available

Back Scattered Dust Monitor (SPM)

Back Scattered Dust Monitor for Ideal Monitoring of Opacity and Smoke Levels in the Exhaust Gas of Industrial Combustion or Air Filtration Processes It is a self-developed online dust monitoring device, that uses the mainstream technology of laser backscatter measurement with imported core components. It is mainly used for continuous monitoring of various sources of emissions of particulate matter concentrations. It can be equipped with CEMS, used alone or with several others, or form a dust monitoring network with shared data acquisition and processing unit.

The backscattered dust monitor is conveniently mounted on one side of the stack and usually requires no light absorber or beam dump on the opposite side of the stack. The backscattered light will be processed by the sensor into electrical signals. The circuit part will realize the photoelectric conversion, laser beam modulation, signal amplification, demodulation, light source power control, V/I conversion, and HMI display. A calibrator is used to generate stable optical signals for zeroing and spanning calibration of the device. The Back Scattered Dust Monitor design has been implementing the concept of “no tool” on-side installation, to minimize the complexity of field installation.


  • laser backward scattering principle can prevent the laser beam from swinging When the refractive index is uneven during the mechanical vibration at an uneven temperature
  • Single-side installation without optical path alignment.
  • The on-site display can read the dust concentration in the field.
  • After the laser beam is modulated, the system can significantly improve its anti-interference ability.
  • The device design has been implementing the thinking of “no tool” on-side installation, to minimize the complexity of field installation.
  • (4-20) mA standard industrial current output makes the connection easy. Device overall power consumption is very low at around 3w.
  • Generally, the standard setup parameters are applicable to the flue wall with a thickness less than 400mm and a diameter greater than the device stack label size. The measuring area can be customized as required. Users may also adjust the area under the approval and guidance of the maintenance personnel and also adjust the area under the approval and guidance of the maintenance personnel.


1. What is working principle of dust monitor

a. Laser Back scattered

2. What will be digital output

a. RS485

3. Up to what diameter it can useful

a. it can be set from 0.5 to 12 meters

4.Does it have calibration audit check facility

a. Yes it has Zero & SPAN check facility

5. What is the most regular problem faced by user and why ??

a. It shows some constant reading, because of moisture content in the purge line

6.What is solution to avoid moisture in the purge line or instrument air

a. We should use FLR before instrument inlet connection

Get in Touch

Have a question about our Device? Don’t hesitate to contact us directly using the form on this page or by visiting our office.


Ph. +91 7337418685

Manjeera Trinity Corporate,
Plot No-112, Survey No:1050,
JNTU, Hitech city Rd, KPHB Colony
Kukatpally, Hyderabad-500072

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