Wireless boosts operational efficiency at brewery

Plzensky Prazdroj in Plzen, Czech Republic, is the leading brewery in central Europe and exports beer to more than 50 countries across the world.

The company continually invests in new technology to optimise its manufacturing and logistics processes and ensure it maintains its market-leading position. The organisation has become more reliant on a network infrastructure based on open standards, industrial Ethernet and wireless communications to assist them in its objective of achieving greater operational efficiency across its processes.

To help the brewery achieve this aim, Siemens Solution Partner, FMA Process Engineering Limited, advised Plzensky Prazdroj to upgrade from the existing Siemens S5 control system on its kegging line to the Siemens S7 system, incorporating ProfiNet wireless communication. This would remove any potential maintenance and downtime issues and loss of productivity caused by an old legacy system.

The kegging line uses three automated carousels which pre-wash, wash and fill kegs 24 hours a day. The line handles one thousand kegs an hour so it was imperative that its new control system could keep pace with this level of production. The carousels, which have been in operation for more than 15 years, were each equipped with 12 S5-95U PLCs each communicating to a S5 115U over a Sinec-L2 network.

The original solution used slips rings to bridge the Sinec-L2 to the carousels. While this solution worked adequately, limited network throughput meant that it was not suitable for high speed data transmissions as part of a new Control System.

To bring both the performance and reliability of the wireless communication network on site up to benchmark standards, FMA installed a solution using ProfiNet and an Industrial Wireless Local Area Network (IWLAN). This provides seamless connection of the ProfiNet network, controllers and I/O modules.

In addition, the existing Siemens S5 software was converted and re-engineered to provide the functionality required to accommodate the upgraded system, and HMIs throughout the site have been upgraded to OPs to provide enhanced operator control. These changes have been crucial to give a more efficient control system.

A total of 14 existing S5 115U and S5-95U PLCs were combined into one CPU416-3 PN/DP processor. All associated I/O was rewired to ProfiNet variants of both ET200M and ET200S remote I/O.

On both the Pre-Washer and Washer carousels, the existing 12 S5-95U PLCs' control was combined into a single ET200S CPU and the remaining stations converted to ProfiNet ET200S remote I/O devices.

On the Filler carousel, the existing 12 S5-95U PLCs' control was distributed across two ET200S CPUs and the remaining stations converted to ProfiNet ET200S remote I/O devices.

Fundamental to the success of any wireless deployment is a wireless survey. As industrial plants typically contain a lot of heavy machinery, metal and concrete, all of which are potential obstacles for wireless deployment, it is vital that solution providers have a full understanding of the potential issues facing a wireless network and build a system which addresses them.

On behalf of FMA, Daconi, a company specialising in wireless networks and technology, worked with Siemens Industry Automation & Drive Technologies to conduct a wireless survey. Daconi determined the optimum wireless network architecture to give the best performance using Siemens simulation tools. A wireless survey was then performed using WiFi survey tools and imported plan drawings of the plant area.

The radio coverage of each access point was measured and the optimum location to install the Access Points and the best antenna and antenna location for the wireless clients was established. The wireless solution was then tested in situ to verify the wireless performance.

The solution includes Siemens Scalance Industrial WLAN access points that transmit ProfiNet wirelessly at the data rate of 54 Mbit/s between SCALANCE W786-1PRO access points and SCALANCE W784-1 gateway clients providing seamless connection of the ProfiNet network, controllers and I/O modules.

Each rotating carousel was fitted with a panel-mounted SCALANCE W784-1 operating in WDS (Wireless Distribution System) mode using an externally mounted Omni-Directional Dome Antenna for 360 deg radio coverage, as the wireless survey showed that this antenna performed better than a standard Dipole type.

The W784-1 units communicate with two girder-mounted IP65-rated SCALANCE W786-1PRO access points utilising internal Omni-directional antennas.

The upgrade solution provided to Plzensky Prazdroj far exceeded its expectations, as Ondrej Sykora, discusses: "There have been significant improvements to the efficiency of the site resulting directly from the installation. We have benefitted from reduced downtime due to enhanced alarming functions which means we can find faults faster and rectify them sooner. Also, we now have quicker resumption of power in the event of a power outage which has improved productivity. In addition, the reduction in numbers of PLCs has meant we no longer have such a reliance on inter-PLC communications where problems were difficult to diagnose and remedy. Our service technicians have also found the PLC code easier to follow now it is in S7 format and, again, this has kept downtime to a minimum and helped ensure the line runs as efficiently as possible."

For more information, visit www.siemens.co.uk/automation

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