Opensoft Systems recently carried out a control systems upgrade concerning a process evaporator at HEINEKEN’s Ledbury Cider Production Plant in Herefordshire.

The Evaporator control system consisted of a Rockwell PLC 5 series CPU (central processing unit) which is long since obsolete and unsupported.

The CPU was in turn connected to six also (obsolete and unsupported) remote 1794-ASB flex I/O racks through a DeviceNet network which was had been experiencing network faults.

The system communicated to a Wonderware InTouch 2014 version SCADA system via Ethernet.

The modifications of the original system consisted of replacing the main obsolete Rockwell PLC 5 series rack with a Rockwell Control Logix rack and then replacing the Device Net ring network with a faster and more responsive Ethernet ring network. 

The existing 1794-ASB Device Net adapters connected to the six remote racks to the main CPU were replaced with new Ethernet adapters and Flex I/O Adapter with two Ethernet ports.

The PLC 80/E model was replaced with a new Control Logix CPU 1756-L71