VEGA VEGAPULS 68 (≥ 2.0.0 - ≥ 4.0.0) 4 … 20 mA_HART - two-wire User Manual

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4 Mounting

VEGAPULS 68 • 4 … 20 mA/HART - two-wire

36535-EN-130205

max. 50 mm (1.97"

)

Fig. 21: Mounting of the instrument with insulated vessels.
1 Electronics housing

2 Distance piece

3 Vessel insulation

For level measurements in concrete silos, the sensors are often

mounted in protective boxes. These boxes can be for example metal-

lic, closed subsurface enclosures.

Fig. 22: Mounting of the instrument in an subsurface enclosure
1 Subsurface enclosure

2 Concrete bottom

For this application, the minimal amounts of stray radiation from the

sensor can be reflected and strengthened by the walls of the subsur-

face enclosures. In the case of sensors with plastic housings, this can

lead to coupling disturbances. This can be avoided by using a sensor

with aluminium or stainless steel housing.

The silo walls of multiple chamber silos are often made of profile

walls, such as e.g. profile sheeting, to ensure the required stability. If

the radar sensor is mounted very close to a heavily structured vessel

wall, considerable false reflections can be generated. Hence the sen-

sor should be mounted at a large distance from the separating wall.

The optimal mounting position is on the outer wall of the silo with the

sensor directed towards the emptying aperture in the silo center.

Installation in subsurface

enclosures

Mounting in multiple

chamber silo