ENDRESS + Hauser has released the Micropilot FMR250 microwave level measuring device for solids applications. It is a loop-powered, non-contact radar level device with a 70m range and 15mm accuracy. It is suitable for operation up to 16 bar process and 2000°C process temperature.
Cabling costs, especially in hazardous areas, are significantly reduced with Micropilot's two-wire, loop-powered design. Measurement accuracy and stability are ensured using a one-second sampling rate.
Earlier ultrasonic instruments monitored levels up to 70m in coarse solids but failed in dusty or hot, high-pressure atmospheres or with high or dynamic angles of repose during filling and emptying. Guided microwave (radar-on-rope) overcame these limitations, but intruded into the process and suffered possible wear and tear. The maximum measured level, up to 35m, was determined by rope length, abrasion and pull-down forces.
Air purging, recommended in serious cases of dust build-up on the antenna of any non-contact microwave device, is a standard capability. Running costs are minimal if purging is maintained at a maximum of hourly 10s bursts.
The Micropilot FMR 250 has a built-in targeting device at the flange which optimises transmitter-mounting, ensuring reliable measurement. It eliminates failure of solids level radar caused by high angles of repose of the material in the bin or silo.
Both horn and parabolic hook antenna designs are available. The horn has a tight 80° beam angle and a maximum process connection diameter of 100mm. The parabolic antenna has beam angle of 40° and 200mm process connection diameter. It is suitable for ideally suited to tall (70m), narrow silos.