welas® digital 3000 — Aerosol Spectrometer

welas® digital 3000 | Light-scattering spectrometer system

Descriptionwelas digital 3000

The new welas® digital 3000, is a highly innovative instrument where two welas® sensors are supplied with one single light source and the scattered light pulses are then detected by a photomultiplier. Fibre optic cables (light wave conductors or LWCs) connect the sensors to the controller. This enables a quasi-simultaneous particle measurement at two sampling locations that are up to 100 metres apart.

The quasi-simultaneous particle size and particle number determination offers particular advantages for characterising filters and particle separators with fluctuating inlet gas particle concentrations.

Using the welas® digital 3000, it's as if the user has two light-scattering spectrometers in one device, but operating with the same characteristics

  • Particle size resolution capability
  • Particle size classification accuracy
  • Counting efficiency
  • Zero counting rate

The various welas® sensors are characterised by a particularly good conformity of counting efficiency and particle size resolution.

All welas® sensors of the welas® digital 2000 series can be used with the welas® digital 3000.

Opto-mechanical switching

Unlike a system which perhaps uses a single sensor to ensure accuracy, but mechanically cycles the upstream and downstream sample steams, opto-mechanical switching allows the two remote welas® sensors that are connected to the single light source to be cycled by switching only the optical signal. The sensors are controlled automatically through software.

The particular advantages over a manual measurement selector switch system are

  • Faster changeover of the measurement location
  • No deposits in sampling lines
  • Long service life; ie. there is no wear of valving seals due to dust particles

Particle Size Spectrometry at Higher Pressures and Temperatures

The combination of the unique welas® sensors with the welas® 3000 control systems allow operation with gas samples at high temperature and higher pressure samples avoiding the issues of condensation and diffusion to atmospheric pressure which can introduce errors in other systems.

The welas® 3000 H control unit offers temperature control of heated welas® H sensors to 250°C and the welas® 3000 P or HP combines mass flow control with pressure and temperature sensing of the sample flow to maintain the constant volumetric flowrate using the welas® P or HP sensors.

Technical parameters

  • Measurement range: 0.2 µm – 105 µm
    • Cn ≤ 106 Particles/cm3
  • Thermodynamic conditions:
    • -90°C ≤ T ≤ 70°C
    • Optional: T ≤ 250°C, p ≤ 10 bar
  • Suction flow rate: 5 l/min
  • Digital individual signal acquisition: 20 MHz processor, 256 raw data channels
  • Light source: 35W Xenon lamp
  • Interface: USB
  • Computer: Standard PC and monitor preloaded with software (Laptop optional)
  • Software: PDControl and FTControl for fractional separation efficiency measurements
  • Power supply: 115/230V ; 50/60Hz
  • Case: Desktop case (19“ compatible, 4 HE, 84 TE, T = 435 mm), optional with mounting brackets for rack installation

Please contact us for more detailed information.