The DT990 combines advanced signal processing techniques with PCME's unique Electrodynamic measurement principal.
When the sensing probe is installed in the duct or stack, particles in the airstream interact with the sensing rod and a charge induction effect is analysed in the probe.
Distributions in the particle stream result in a frequency charge induction response, which is directly proportional to the concentration of particulate (application dependant).
The instrument's output is an analysis of this frequency response and can be calibrated in mg/m3 by comparison to reference iso-kinetic sample results. This technique has acheived ISO 10155, MCERTS & TUV approval.
Unlike Triboelectric systems, the Electrodynamic measurement is not significantly affected by velocity variations between 8m/s and 20m/s and is not affected by build up on the rod surface. The DT990 is, therefore, suitable for emission measurement in the most aggressive environments including those stacks with variable velocity.
In addition, PCME's Electrodynamic technique enables the use of patented fully insulated probes, essential for high humidity gas streams and applications with high conductive dust loadings.
Very low concentrations (<0.01 mg/m3) can be measured due to this unique measurement principal. Automatic gain controls allow the system to optimise its response to varying dust levels e.g. pulsing bagfilters
Features of DT990 Particulate Monitoring Systems include:
- Normalisation for T and O2*
- Mass calculation (kg/year) capability for both fixed and varying
- Broken Bag diagnostics for pulse cleaned Bagfilters velocity applications (varying velocity requires velocity input)
* Assumes input from appropriate montor
Advanced Sensor Features
Advanced probe and quality assurance checks
The DT990 includes the most advanced automatic functionality checks available on any probe system to provide full regulatory compatibility
The unique contamination circuit monitors for any leakage currents or signals across the insulator, hence providing the ultimate proof that the sensors measurement integrity is uncompromised.
The automatic zero and span checks then provide proof that the electronic amplification and conditioning of the signal is performed within pre-defined tolerances. The above features form part of World-Wide Patents.
- Zero Check
- Span Check
- Contamination Check
Applications of DT990 Particulate Monitoring Systems
Particularly suitable for bag filter, cartridge filter, dust collector and cyclone applications.
Enhanced measurement accuracy
Advanced signal processing techniques are used within the sensor electronics to provide the following measurement features:
- Rapid Dynamic Ranging of 10,000: 1 (Dynatrack) permitting bag cleaning pulses to be accurately monitored while maintaining high accuracy in background emission measurement
- Rolling digital average calculations for accurate emission reporting