As the lines blur between PC and PLC, users of packaging machinery are reaping the benefits, Packaging magazine reports.
Thanks to internet-style graphic controls, it is now possible for an operator with minimal training to set up and maintain sophisticated packaging machinery, without having to learn PLC programming, according to SMI Pacifica ’s Steve Warren.
He pointed to SMI shrink-wrapping and carton wrapping machinery which he said had been at the forefront of graphic control since 1996, using standard PC mother boards and touch screens driven by dedicated packaging software.
“The same machinery will interface seamlessly with computer controlled environments and PLC equipment, giving investors the best of both worlds.
“Experienced PLC managers can understand the SMI plain-language interface as soon as they see it. But more importantly, after a few days training, low-skilled operators can trace and correct faults easily, usually without even having to stop the line, let alone call for expert help,” Warren said.
Problems caused by variations such as humidity or consumables changes could be fine-tuned to within microns.
Instead of complex ladder-logic, SMI machines displayed simple prompts like ‘pack down’ or ‘carton feed empty’ to ensure that housekeeping was kept up to standard, further reducing the risk of
stoppage through human error.
Should a more technical or intermittent fault arise, for instance a sensor misreading, the system maintained a cycle-by-cycle record of every component¹s activity. The operator could isolate the culprit almost immediately and confidently reset or replace it.
“The old timewasters of dismantling and readjustment are minimised, as most components are electronically rather than mechanically connected,” he said.
This ‘keep it simple’ philosophy was made by possible by SMI¹s dedicated software, written specifically for the packaging industry. SMI software communicated via Serial Real-time Communication System (SERCOS) interface which was steadily becoming the standard for motion control.
SERCOS replaced bundles of wiring with a vastly simpler fibre-optic network. Benefits included faster installation, accurate communications impervious to electronic noise, more reliable connections and simpler servicing.
“Their PC based control boards are more versatile and economical. Manufacturing and installation are also streamlined, resulting in significant capital savings for the purchaser,” he said.