ACCURATE level measurement of strongly foaming liquids can now be achieved more reliably with the latest version of SICK’s LFP Inox probe.  The guided-radar probe incorporates a patented SICK algorithm in its firmware that discounts false signals caused by foam.

Trials of the updated LFP Inox in UK industrial process applications have shown that excellent success rates are possible for measuring levels accurately in liquids such as milk, beer and detergents in the presence of  wet, dense foams.  The results show significant cost savings are likely for vessel level measurement and bottle filling applications.

The LFP Inox is a hygiene-compliant level probe that uses guided radar technology, so it is largely unaffected by a liquid’s density or conductivity.  False readings can be a common problem in level measurement using multi-point float switches, capacitive sensors or hydrostatic pressure sensors.

“Trials of the LFP Inox ’s unique foam algorithm on high-speed bottle filling lines, for example, have shown that wastage caused by under or over-filled bottles and line downtime due to false head tank level readings can be significantly reduced,” explains Darren Pratt, SICK (UK) industrial sensor specialist. “Conventional level sensors are often unable to distinguish between foam and liquid hence bottles are frequently under-filled resulting in a high percentage of rejects.

“By using the LFP Inox level sensor, the bottling line tank levels were kept consistently topped up to enable gravity feed of the bottles on the 100+ unit per minute lines. The filling unit operators were very pleased as the efficiency of their production lines has been significantly improved.  We would be very interested to conduct trials with other processors encountering difficulty determining fluid level   in the presence of foam.”

The stainless steel probe of the SICK LFP Inox can be cut down from its maximum four metres length to suit the vessel dimensions, and can even be used in small vessels, thanks to its deadband of just 25mm.

With a hygiene-rated IP69K housing, the LFP Inox covers temperatures from -20oC to +150oC and pressures from -1 to +16 bar making it suitable for a wide range of processing conditions.  It is resistant to the thermal shock from rapid temperature changes and cleaning cycles with aggressive chemicals.

The easy to read on-unit display gives real time level and status information and makes LFP Inox  very simple to set up and commission. There are no moving parts, so years of reliable life are delivered by this robust, low maintenance solution.

“The accuracy and reliability of the LFP Inox once installed, can throw light on the performance of other elements in process equipment, such as suction leaks, air ingress and other common faults,” points out Darren Pratt. “Experience has shown that the inefficiencies of false readings caused by foam can mask other problems which, when isolated and corrected, can improve the efficiency of the whole process, delivering an excellent return on investment for a processor.”

For more information on the new SICK LFP Inox  fluid level sensor, please contact Andrea Hornby on 01727 831121 or email


Press Enquiries to:

Sharon Lindsay, Sharon Lindsay Communications. Email

Tel:  07928 809035; Fax 0161 282 6168.


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