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Radar sensor VEGAPULS 68 – a Tough Instrument for Tough Environments

Level measurement of bulk solids
 
Bulk solids, which vary widely in their density, form and features, confront the measuring instruments in industrial production processes with widely different challenges: powders often generate huge clouds of dust, while coarse, heavy bulk solids cause tremors and noise when being filled into a container from a great height. With VEGAPULS 68, level measurement in bulk solids is largely independent of process conditions. Due to optimized VEGA radar technology, the sensor can evaluate signals 1,000 times smaller than those conventional radar instruments can pick up. This high sensitivity allows a measuring range of up to 75 m even in products with bad reflective properties.  

Area of application
VEGAPULS 68, the level specialist for extreme bulk solids applications, fulfils all requirements for precise, reliable level detection of bulk solids in high-temperature or dusty environments such as coaling stations in power plants or storage facilities for building materials like clinker or cement.
Because of these advantages, the robust VEGAPULS 68 is highly valued especially in the steel industry, in the building sector, in plastics processing as well as in the food industry and in the chemical and pharmaceutical sector.
 
Advantages
VEGAPULS 68 is completely unaffected by dust, temperature, pressure, concussions or filling noise:

• Non-contact measurement
• Measuring range up to 75 m
• High measuring precision
• Simple installation
• SIL qualified
  

Technical data

Documentation

Brochure
Product catalogue
Radar VEGAPULS
Product information
Level measurement in solids: VEGAPULS 67, 68
Specification sheet - VEGAPULS 68
4 … 20 mA/HART - two-wire
4 … 20 mA/HART - four-wire
Profibus PA
Foundation Fieldbus
Operating Instructions - VEGAPULS 68 - Hardware version ≥ 2.0.0 - Software version ≥ 4.0.0
4 … 20 mA/HART - two-wire
4 … 20 mA/HART - four-wire
Foundation Fieldbus
Profibus PA
Operating Instructions - VEGAPULS 68 - Hardware version < 2.0.0 - Software version ≤ 3.8
4 … 20 mA/HART - two-wire
4 … 20 mA/HART - four-wire
Foundation Fieldbus
Profibus PA

Drawings - VEGAPULS 68

Horn antenna - flange - 130°C

Horn antenna - flange - 130°C - purging connection

Horn antenna - flange - 200°C

Horn antenna - flange - 200°C - purging connection

Horn antenna - flange - 200°C - purging connection - antenna extension

Horn antenna - flange - 250°C

Horn antenna - flange - 250°C - purging connection

Horn antenna - flange - 450°C

Horn antenna - thread - 130°C

Horn antenna - flange - 130°C - purging connection

Horn antenna - flange - 130°C - purging connection - antenna extension

Horn antenna - thread - 200°C

Horn antenna - thread - 250°C

Horn antenna - thread - 250°C - purging connection

Horn antenna - thread - 450°C

Horn antenna - swivelling holder - 130°C

Horn antenna - swivelling holder - 130°C - purging connection

Horn antenna - swivelling holder - 200°C

Horn antenna - swivelling holder - 250°C

Horn antenna - swivelling holder - 250°C - purging connection

Parabolic antenna - flange - 130°C

Parabolic antenna - flange - 130°C - purging connection

Parabolic antenna - flange - 200°C

Parabolic antenna - flange - 200°C - purging connection

Parabolic antenna - thread - 130°C

Parabolic antenna - thread - 130°C - purging connection

Parabolic antenna - thread - 200°C

Parabolic antenna - thread - 200°C - purging connection

Parabolic antenna - swivelling holder - 130°C

Parabolic antenna - swivelling holder - 130°C - purging connection

Parabolic antenna - swivelling holder - 200°C

Parabolic antenna - swivelling holder - 200°C - purging connection

Drawings - Housing

Plastic, cable entry M20 x 1.5

Plastic, cable entry ½ NPT

Plastic double chamber, cable entry M20 x 1,5

Plastic double chamber, cable entry ½ NPT

Aluminium, cable entry M20 x 1.5

Aluminium, cable entry ½ NPT

Aluminium double chamber, cable entry M20 x 1.5

Aluminium double chamber, cable entry ½ NPT

Stainless steel (electropolished), cable entry M20 x 1.5

Stainless steel (electropolished), cable entry ½ NPT

Stainless steel (precision casting), cable entry M20 x 1.5

Stainless steel (precision casting), cable entry ½ NPT

Stainless steel (precision casting) double chamber, cable entry M20 x 1.5

Stainless steel (precision casting) double chamber, cable entry ½ NPT

Cement and lime: storage of raw materials and finished products

The last step to the finished product

After the limestone has been burned to quicklime and the raw flour to clinker, the products are stored for further processing. Beside the intense dust generation, the partially high product temperatures and the aggressive properties of the dust make high demands on the measurement technology. Depending on the production capacity of a cement plant, the clinker silos can be of considerable size, not infrequently reaching a height of over 50 m (164 ft).

VEGAPULS 68 for level measurement in the clinker silo

Due to the highly abrasive properties of the clinker and temperatures up to 200 °C (392 °F), measuring techniques that have physical contact with the medium are completely out of the question. The radar sensor VEGAPULS 68 combines very simple mounting and set-up with wear-free, contactless measurement. The parabolic antenna is particularly suitable for large silos, as it provides optimal focussing of the microwaves. In silos with very large dimensions, several sensors are sometimes used to capture the complete profile of the product surface.

VEGACAP 65 as overfill protection

Ruggedness is of utmost importance in the clinker silo. That is why capacitive measurement lends itself well to this application. VEGACAP 65 is characterised by a stable, wear-resistant mechanical construction and an easy set-up procedure. Neither condensate nor build-up can impair its reliability as overfill protection.

VEGAPULS 68 for level measurement of fine lime, raw flour and cement

Extreme dust generation during the filling of powdery products often makes contactless measurement with ultrasound impossible. VEGAPULS 68 provides a good solution here, since microwaves are not influenced by the filling stream and the dust. With a measuring range up to 70 m (230 ft), the VEGAPULS 68 radar sensor is the ideal measuring instrument for this application. It can be optimally aligned to the product surface with a swivel mount.

Level measurement with VEGAFLEX 62

The medium-contacting sensor VEGAFLEX 62 works reliably and trouble-free in cement silos up to 40 m (130 ft) high. Because the sensor comes already calibrated to the probe length, adjustment on site is not necessary. Set-up thus involves only electrical connection of the two-wire sensor. Product changes, such as e.g. an admixture of aggregates, have just as little effect on the measuring results as varying product quality does.

Overfill protection with VEGAWAVE 62

The vibrating level switch VEGAWAVE 62 lends itself well as overfill protection. It requires no adjustment whatsoever and provides reliable switching with varying product quality in the silo. For the user this means: “plug and play”. Since VEGAWAVE 62 has practically no moving parts, it is not subject to wear and is maintenance-free throughout its entire life cycle.

Flour Silo

High and dusty

Flour is usually stored in narrow, 30 m (98.4 ft) high concrete silos. For space-saving storage of several types of flour, the individual storage cells are approx. 2 x 2 m (6.5 x 6.5 ft).
For applications in solids, the choice of measuring principle depends not only on the measuring range, the degree of dust generation and dielectric constant of the product. Large extraction forces during the emptying process also play into the equation and may cause mechanical damage to the measuring instruments. In many cases, a weak ceiling construction will not allow measurement with a contacting measuring principle.

Level measurement with VEGAPULS 68

For measurement in the flour silo, radar technology offers the advantages of contactless measurement. Since dust particles have only a minimal damping effect on the microwaves, the VEGAPULS 68 radar sensor works well even with pneumatic filling. The high sensitivity of the sensor also guarantees high performance for varying surface geometry.

The optional swivelling bracket enables optimal alignment to the product surface and reduction of false echoes from the vessel wall.

Please call for more RADAR THE PULSE product information

1-800-755-4507

Copyright 1999 - 2005 HiTECH Technologies, Inc.

All rights reserved.

Last revised - December 30, 2005