Case Study: Tomago Aluminium Bake Ovens

Scope: Design, manufacture, install and commission a replacement control system for Fume Treatment Centre control systems an Anode Bake Oven plant.

The main task of the FTC is the cleaning of the Bake Ovens Fumes, which is an important part of Tomago Aluminium’s ongoing commitment to environmental management. The system was originally controlled by three main and six filter control Telemecanique PLC’s. These were replaced by Siemens S7 300 and ET200S Profibus DP Slave PLC’s.

Due to the required high availability of the control system, shutdown time was virtually none existent and only limited hours of manual plant control could be tolerated.

A changeover methodology was devised in consultation with Tomago Aluminium to minimise shutdown times and any risks associated with the changeover. It included not only a thorough Factory Automation Test but also a parallel installation of each PLC’s, which allowed I S Systems to fully verify the functional integrity of the converted code.

Control was then converted to the new S7 with the bonus that it could have been swapped back to the old system at any stage, thus minimising the risk of the upgrade. This, however, was never required, because of expert software design and smart symbol based mapping of the Telemecanique’s memory structure in the new S7 PLC’s.

Client: Tomago Aluminium