Electricity + Control March 2021

MEASUREMENT + INSTRUMENTATION

Smart sensors and IoT are changing logistics

Level sensors and LoRaWAN technology optimise the logistics of circulating containers that transport raw materials between manufacturers and consumers. Michael Bozek of Pepperl+Fuchs explains how the use of low-power wide-area network technology saves energy and enables users to operate a private wireless network on-site.

A utonomous level sensors and new wireless technologies that can be operated privately on a company’s premises provide a solution to logistics managers’ need to keep track of moving containers and when they require refilling. Mobile containers report independently With the Internet of Things (IoT), objects that previously did not have their own ‘voice’ now have a chance to ‘speak’. Today, battery-powered sensors can capture key data about the location and fill level of mobile containers, tanks and silo containers and provide this information to the logistics supply chain. One example of this is in mobile silos that are used to transport plastic granules from the manufacturer to the processing injection-moulding company. At the injection-moulding site, the granules are gradually removed and the empty container is sent back to the manufacturer. In this circulation system, hourly information about the location and fill level of the silos is especially valuable because it can prevent the supply chain from being broken, as it could be if the information were not available. In the application described above, the sensor becomes the intelligent control unit of the silo tank. In this mobile system, the sensor must be able to manage without an external energy supply. This gives rise to a demand to use the available energy as efficiently as possible to achieve the longest battery life possible. Low-power wide area network (LPWAN) technologies provide a good solution to meet these requirements. They ensure low energy consumption with a long detection range for radio signals and enable sensors to transmit data with a battery for several years and over many kilometres. In addition to the energy and detection range parameters, a distinction can be made between SIM-based and SIM- free LPWAN technologies. In SIM-based technologies, a mobile service provider provides a public wireless network. SIM-less wireless technologies can be set up and operated privately. Such private wireless networks offer the company Energy-saving wireless transmission of sensor signals

Ultrasonic level sensors and LPWAN technologies can optimise the logistics of managing mobile raw material containers.

The WILSEN.sonic.level battery-operated wireless fill-level sensor ncorporates LoRaWAN technology.

independence from the network provider and better cost control over the long term.

LoRaWAN for a private wireless network The low power wide area network technology particularly well-suited to establishing private enterprise networks is LoRaWAN – a long range wide area network. Sub-gigahertz bands allow LoRaWAN technology to achieve very long detection ranges with good coverage in buildings. As such,

Electricity + Control MARCH 2021

19