Solid Fuel Boiler PLC Upgrade
Mt Gambier, SA
BJH Controls was commissioned to upgrade the existing, obsolete Toshiba PLC and loop controller system with a modern PLC to control the firing of two boilers for its customer in the timber industry.
Equipment obsolescence meant that program changes and tuning of the process were unable to be made, leading to regular controller failures. Being over 50 years old, the boilers were without any functional description or documented control.
A Rockwell Automation ControlLogix solution was chosen, replacing the existing three Toshiba PLCs and five loop controllers with a single PLC with multiple I/O racks. The advanced capabilities and performance of ControlLogix gives BJH Controls and its customer greater customisation of the program.
The first stage was to understand the existing system and adapt that to the ControlLogix. BJH Controls wrote the program off-site utilising some of the more advanced function block instructions including PIDE and Totalisers, and utilised the add-on instruction capabilities of the ControlLogix.
During the engineering simulation, the company configured and tested communications between the PLC, 3 I/O racks, and Factory Talk View SE SCADA system. The steam plant’s existing manual control panels were updated, involving replacing manual controls and re-wiring.
As a result of the upgrade, the customer has received greatly improved plant efficiencies, and is able to easily implement process improvements and trouble-shooting.
Fuel burn and combustion efficiencies have reduced the fuel level required to feed the boilers, resulting in an excess of available fuel to be on-sold.