Level measurement

104 Continuous level measurement in bulk solids

1. Overview of the measuring principles

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Radar Micropilot works with either pulses or with Frequency Modulated Continuous Wave (FMCW). Pulse: High-frequency radar pulses which are emitted by an antenna and reflected from the product surface. The time between pulse launching and receiving is measured and analyzed by the instrument and constitutes a direct measure for the distance between the antenna and the surface of the medium. FMCW: Works with an FMCW continuous electromagnetic wave which is emitted from an antenna and reflected by the product surface. measured and the time and distance are calculated. Guided radar Levelflex works with radar pulses guided along a probe. As the pulses meet the medium surface, part of the emitted pulse is reflected due to a change of the DC value between the air and the medium. The time between pulse launching and receiving is measured and analyzed by the instrument and constitutes a direct measure for the distance between the process connection and the product surface. Ultrasonics Prosonic works with ultrasonic pulses which are emitted by a sensor, reflected by the surface of the medium due to a change of the density between the air and the medium and again acquired by the sensor. The required Time-of Flight is a measure for the distance travelled in the empty part of the silo. This value is deducted from the overall height of the silo to yield the level.

Micropilot Non-contact, maintenance-free measurement also under extreme conditions. Unaffected by the density of bulk solids, temperature, dust formation and humidity.

Levelflex Robust, non-maintenance measurement in solids. Unaffected by the density of bulk solids, temperature, dust formation and humidity and almost unaffected by baffles.

Prosonic Non-contact measurement free of maintenance without impairment constant or humidity. Unaffected by build-up due to the self-cleaning effect of sensors using diaphragm vibration.