Low-cost SCADA brings robot control to tissue packing line

Northwood & WEPA specialises in the production of bathroom and kitchen rolls and aims for market recognition for its quality, service, innovation, sustainability and price. The plant in Bridgend near Cardiff has both tissue making and converting operations. Packing and dispatch of the finished products is a complex operation because the company produces many different sizes of multipack and these are arranged on pallets for transportation in many different patterns.

The production hall is used for packing and has a shuttle conveyor to deliver batches of products to one of two robotised palletising stations. Northwood & WEPA brought in electrical and automation specialist Platinum Controls from nearby Neath to work on the control systems. Stephen Vincent, Technical Director of Platinum, recalls how the project developed.

Vincent says: "We reviewed the site and looked at options for control solutions. One of our key recommendations was to use a flexible but competitively priced SCADA (Supervisory Control and Data Acquisition) package. The one we recommended was Movicon made by Progea in Italy and available in the UK exclusively through Products4Automation (P4A), with whom we have worked on several other projects. We have always found the Movicon product to be very cost competitive yet highly functional. It is also easy to programme, install and commission, so saves us time in commissioning."

Robots have become increasingly popular for palletising duties in recent years because of the weights they can lift without risking repetitive strain injuries and the productivity levels they can achieve. This is coupled with their ability to execute a number of different loading patterns and the flexibility to change quickly from one product or sequence to another.

The system designed by Platinum Controls is based on Movicon SCADA technology. It controls the robot's programs from a database of many different pallet filling patterns which are chosen according to the size and shape of the multipacks being palletised and/or to meet individual customer preferences.

New stacking patterns

Operators interact with the robots via an industrial keyboard and a 21-inch touch screen monitor mounted on the electrical control panel. At these they are able to enter a password and easily select the required stacking pattern. They are also able to develop and store new stacking patterns from the control panel, which previously had to be done by the production/engineering team.

Vincent says: "These new patterns are stored in the database under names added by the operators themselves, rather than using long reference numbers. This small change has proved popular and effective because the reference numbers were difficult to remember, whereas the names are completely intuitive."

The hardware used in the control system includes two PLCs (programmable logic controllers), one communications driver, 9211 I/O and a PC that can display over 50 different information screens.

Movicon is a SCADA system based on XML and Web Services technologies, making it easy to understand and intuitive to use. Its modular design allows bespoke systems that meet the exact needs of each application to be built quickly and simply. As it is almost inevitable that applications need to change, develop and grow over time, Movicon's developers were careful to make sure that expansion and alterations to systems are also straightforward.

Paul Hurst of Products4Automation says: "Movicon is designed to improve productivity, reduce integration times and operating costs, and to optimise asset utilisation. We sell it as a pure software package, or installed on an industrialised PC or HMI product. Fast control and visualisation, in addition to good data recording made it an ideal choice for the palletisation application."

Movicon is designed to be easy to use, while providing open connectivity, compliance with multiple standards, reliability, security and reusability. Hurst goes on to explain that there are no additional development fees with Movicon, hence the always-competitive prices that Products4Automation quotes.

At Northwood & WEPA the Movicon system is integrated with other plant wide control systems so that it is co-ordinating packaging with production and order dispatch requirements.

To learn more about Movicon SCADA software please go to www.products4automation.co.uk.