Heavy Clay

Tunnel Kiln Control system upgrade 

Overview

UCS supplied a complete upgrade for a Gas Fired Tunnel kiln control system.

Upon assessment of the existing control system it would seem the plant has been modified many times leaving the plant with a convoluted mix of equipment, some of which is serving little or no purpose.

We therefore proposed that the following work be carried out to completely overhaul the Control system:

• Removal of the existing redundant Siemens S5 PLC;
• Removal of the existing Eurotherm door mount instrumentation panel;
• Removal of existing Eurotherm PC3000 control panel;
• Removal of existing Eurotherm 2500 control panel;
• Removal of existing Wizcon Scada system;
• Supply of new Siemens S7 300 based PLC control panel system to replace all 3 Eurotherm panels;
• Supply of new Siemens Win CC Scada system to replace existing Wizcon Scada.

The existing kiln control was achieved via both door mounted instrumentation and a PC3000 rack based system in the control room, with an additional Eurotherm 2500 system used to monitor additional thermocouples and analogue pressure variables together with damper control outputs and the hardware to monitor numerous plant status conditions. Upon inspection it seemed that very few of these digital inputs from the haulage automation system were actually connected to anything, and are therefore redundant.

The new Siemens based PLC system greatly simplified the control of the system, with everything carried out via a single PLC CPU. This PLC was connected via ‘comms’ to the new Siemens haulage PLC’s, currently being upgraded. This allowed us to design a new SCADA system to supervise the entire plant associated directly with the Kiln.

What was developed?

UCS developed a version of PLC & SCADA operator system for the use in controlling various process variables on a Tunnel Kiln.

What previously existed in this field?

Outdated instrument control.

What is the advance / appreciable improvement?

The improvement was a greatly simplified control of not only the Tunnel Kiln but also the associated haulage plant.

What were the technological uncertainties?

The major uncertainty was how to implement the new control system into a Kiln that was using old sensing devices and then making sure that control would reach the anticipated simplicity.

Gaining access to the existing S5 PLC software, Wizcon SCADA, Eurotherm instrumentation & PC3000 and having an understanding of the control so as to use this as the template for the new software.
How and when were the uncertainties resolved

UCS Software engineers used improvised laptop PC’s to gain access to the S5 PLC software and Wizcon SCADA Software. This was achieved over 8 weeks September – October 2014  

Testing of the software I/O control and SCADA were performed in the workshop environment before being installed and fully commissioned at the clients site. All further developments were made during the 10 days spent commissioning the system, these consisted mainly of enhancements & requests direct from the operator.   No limitations were encountered and the system was proved to be a far superior solution to that previously used.