Drives and Automation were approached to upgrade a Hot Wire Cutter running on obsolete control equipment that was proving costly to both maintain and troubleshoot.

The Cutter was no longer capable of operating in variable temperature control, and a number of other features were either not working or required modification. Due to the age of the machine and incomplete or missing documentation, the customers own engineers were unable to make these changes.

During operation the hot wire was required to travel all the way down the table before returning to the top to start the next cycle, slowing down production.

The existing control desk used an obsolete Moeller Easy822-DC-TC PLC, which presented additional challenges for the customer when modifications were wanted.

Following a site meeting with the customer it was quickly determined that the Hot Wire Cutter was a critical piece of machinery, with downtime due to outages being costly and interrupting site production.

In order to minimise downtime and keep disruption to production at a minimum, DnA proposed that the best solution would be to supply a new control desk incorporating a modern Control Techniques C300 inverter, and a Siemens S7-1200 PLC with new control gear.

For the customer this approach had a number of benefits, the new desk could be built and electrically tested offsite, with software written and tested off site as well.

On arrival the existing desk was removed and the new desk was installed in the same location, so that the only downtime required was to swap over the wiring and to complete final commissioning.

As part of the software design, the function of the machine was modified so that it is now possible to cut in both directions, and travel to the end of the table before starting the next cutting cycle was no longer required. These modifications have effectively doubled the production capacity of the cutter.

The existing E-Stop provision on the cutter was also upgraded to dual channel during the retrofit.

The scalable SIMATIC S7-1200 PLC controllers have integrated inputs and outputs as well as communication options and are modularly expandable.


The Control Techniques Commander C Series Inverter Drive combines efficiency and reliability to offer optimum performance for a wide range of applications. With many essential features built in, including PLC capabilities for simple programming needs. The Drive has a dual STO safety function, braking transistor and PID control, and it provides a compact solution for any installation.

Drives and Automation (DnA), based in Chesterfield, provide a comprehensive system design, control system manufacture and project management service for new and retrofit control systems. Working alongside machine builders or end users, we provide systems encompassing AC and DC drives, PLC systems and turnkey project solutions.

Problem Solved
Existing drive control system difficult to maintain
Control system obsolete and unreliable poor availability of spares
Extended downtime and loss of production
Expensive to maintain

Modern AC drive solution
Machine safety improved
Existing motors retained
Control system now reliable and supportable
New PLC Machine Control
Improved machine diagnostics
Comprehensive control system documentation and operation manual provided

Downtime Reduced
Production Increased
Easy to Maintain and Fault Find
Easy to Support



Technical Details
Installation of modern Control Techniques C300 Drive
Installation of Simatic S7-1200 PLC
Up to date drawings and documentation
Simplified diagnostics
Minimised downtime