Level measurement in hygiene sensitive industries such as food and pharmaceuticals has just become simpler, safer and more accurate with the release of Endress+Hauser’s Levelflex M FMP43. The probe features a highly polished easy-to-clean surface, is unaffected by SIP and CIP cycles and may be used in small tanks. High pressure, hot water washdowns may be safely carried out as it meets IP69K, the highest ingress protection rating. A simple calibration kit allows the FMP43’s accuracy to be validated in minutes, without interrupting the process.
The FMP43 uses the well established guided microwave (TDR) principle. A low energy electromagnetic (microwave) signal is pulsed down the probe to the liquid, the signal is reflected from the surface of the medium and the level accurately calculated using the time-of-flight principle.
The stainless steel probe (SS 1.4435) has been electro-polished to Ra = 0.38 microns making it the only product of its kind to meet the highest FDA regulations 21 CFR Part 177.2600 for hygienic applications as well as Biocompatibility USP Class VI. Probes are available in lengths from 300mm to 4m. Endress+Hauser’s FMP43 design follows the latest guidelines for bioprocess equipment ASME BPE (2005). It has also gained 3-A and EHEDG approvals.
In a significant technology breakthrough, Endress+Hauser have been able to employ an extremely narrow frequency band, significantly reducing the ‘blocking distance’ at the top of the vessel and the minimum distance from the probe end to the bottom of the vessel has been reduced to just 10mm. The FMP43 may also be used in vessels as small as 300 mm and work at process temperatures -20°C to +150°C.
The use of spray balls and strong cleaning agents typically employed in the food and pharmaceutical industries have no adverse impact on the operation of the probe. The stainless steel transmitter housing and the cable glands meet the highest ingress protection rating – IP69K – which effectively translates to 100 bar water jet pressure at +80°C water temperature, as typically experienced with high pressure washdowns.
Very often, biochemical and food processes require the vessels to go through an autoclave where the liquid is pressurised and heated to high temperatures. The common practice was to remove all sensitive level measuring devices and seal the vessel prior to sending it into the autoclave.
With the FMP43 this is no longer required as the probe can be left installed since the transmitter with the electronics is easily detached and replaced with a protective sealing cover avoiding the need to open the vessel and remove the probe. Apart from boosting process safety, this is also a significant time saver.
To maintain batch integrity and meet regulatory standards in the hygienic industries, it is important to regularly validate the accuracy of the measuring equipment and typically the wet calibration procedure was employed. This required water or similar medium to be filled into the vessel and level readings then compared to a reference.
With its unique calibration kit, the FMP43 eliminates the need for any process interruption or downtime and reduces the calibration procedure to a few minutes. The calibration kit includes of a set of four reference cables of defined lengths each corresponding to a different level within the measuring range. Calibration is then simply a matter of disconnecting the transmitter from the probe and connecting it to a reference cable.
The Levelflex FMP43 is unaffected by gas mixtures, vacuum, changes in temperature, pressure, density, or conductivity of the substance being measured. The Levelflex M FMP43 is the world’s only guided wave radar level measuring device that meets the highest bioprocess and hygiene standards.