Electricity and Control February 2021

SENSORS + SWITCHES

At a glance  Different sensors monitor the automated production process to ensure the systems run smoothly, supporting a productivity level of 99.6%.  Capacitive sensors, diffuse reflection sensors, and magnetic inductive flow meters are used at various points in the plant to monitor specific processes.

The ifm O6-series diffuse reflection sensors monitor the flow of material.

the LED behaviour and a support engineer can easily ad- vise corrective measures. By using non-contact potentiometers, the new units have the high protection rating of IP69K and are well suited for use in medium temperatures up to 110°C. Moreover, differ- ent functions such as PNP/NPN or NC/NO can be selected. The ifm sensors are equipped with IO-Link, so the user is set up for Industry 4.0. Photoelectric sensors Numerous diffuse reflection sensors are installed at the conveyor belts in the production plant. They monitor the flow of materials – individual slices of crispbread, for exam- ple, or completely packed products in the dispatch area. In most cases, Leksands Knäckebröd uses the ifm O6 type diffuse reflection sensors. The sensors’ optical performance is excellent. They are distinguished by a noise-immune background suppression function and the range of up to 200 mm is achievable independent of the object colour. This is important as the crispbread slices have different surfaces, depending on the type and recipes. Even if there is vapour or dust in the environment, or in highly reflective environments, the automatic sensitivity compensation guarantees reliable function. The clean round light spot ensures consistent light distribution in the light cone. Scattered light around the operating range is avoided. The compact O6 WetLine is designed for use in wet areas. The two setting potentiometers are fitted with a double seal. Front pane and potentiometer are embedded flush to allow residue-free cleaning. These compact powerful units can also be supplied as through-beam and retro-reflective systems. The robust and corrosion-resistant stainless steel hous- ing with protection rating IP68 or IP69K ensures reliable long-term use, even under severe conditions. The O6-series sensors are also available with IO‑Link. Via this interface, the range, sensitivity, light-on/dark-on modes, switching delay or deactivation of the operating elements, for example, can be set remotely. Magnetic inductive flow sensors As well as the grains, water is an elementary ingredient in the crispbread dough. In the field of dough production, a magnetic-inductive flow meter from ifm is used. These units feature high accuracy, measurement dynamics and repeatability. They are suitable for conductive

media from 20 µS/cm. The 4-digit alphanumeric LED display is clearly visible. Besides the volumetric flow, the units also measure temperatures Right: The amount of water for dough production is precisely monitored by magnetic inductive flow meters. Above: The O1D sensor with time of flight technology enables position detection across longer distances.

from -10 to 70°C. With integrated temperature monitoring there is no need for an additional measuring point. The robust, compact housing of the flow meter, use of resistant materials and a pressure rating up to 16 bar allow for flexible use. With IO-Link technology, process values are available via the analogue output as well as digitally. This means there need be no conversion losses during measured value transmission. All sensor parameters can be saved, with simple and quick configuration and remote parameter setting functionality. Saved parameters also allow for easy replacement of sensors when necessary. Looking ahead Leksands Knäckebröd has been using reliable, long-life sensors from ifm for a long time. There are ifm sensors already older than 25 years in some places in the plant. The company is also looking towards tack- ling new challenges in automation. Peter Joon says, “For the future, we need to develop sensors that can perceive the different texture and shades of the bread. ifm is working with us on the development of these sensors. We have created a new area which is based mainly on ifm products and this has proven its worth, so we will develop our future areas similarly. Ifm has the products we need.” □

For more information visit: www.ifm.com

Electricity + Control FEBRUARY 2021

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