Maintenance training is different with modern automation systems
When students arrive at Randy Horton’s maintenance training classes at the ELAU tech center outside Chicago they may expect to receive a crash course in motion and logic programming.
Instead they find that they’re much more likely to be troubleshooting a damaged cable or worn machine slide than altering a program written by controls engineers.
“What we’re about is empowering our students with a methodology and an awareness of the tools built into the ELAU system. We focus intently over a four-day period on how to resolve the problems they’re most likely to face in the real world.”
Lesson #1: smarter servos simplify training
With the self-aware motors and drives available today technicians are not likely to be parameterizing or tuning replacement servos anymore. While there are still many older control systems that require these specialized skills just to set up they’re no longer used on true third generation machines.
The current state of the art embeds chips in the motors that make the servo drive aware of their specifications. The servo drive automatically makes the adjustments needed to properly run the motor and to operate on the motion network.
Likewise there’s no reason to practice downloading of control programs to a replacement controller today when all the software should reside on a Compact Flash memory card. It can simply be pulled out of one controller and plugged into another. (Students are advised to save a backup Flash card and store it somewhere safe).
Lesson #2: Learning to use handy software tools
This technology allows students to concentrate on learning to track and interpret meaningful performance metrics and interacting with the software’s diagnostic tools. These are not unlike the tools used by auto mechanics to diagnose the information contained in a car’s onboard computer.
Each student works hands-on on his or her own PC diagnostic software and PacDrive controller with two operating motor/drives and simulated I/O.
For example students in Horton’s courses become familiarized with the Trace Logger function. This is a powerful tool that goes beyond the familiar oscilloscope to uncover hidden performance trends and prevent problems by adhering to a recommended lubrication schedule changing a worn bearing or controlling power spikes.
They also discover the Data Logger that lets them go back in time and look at events that will help them determine the root cause of a problem.
Lesson #3: servo faults aren’t necessarily the servo’s fault!
When a packaging machine operator sees a fault code being indicated on a servo drive it’s only logical for him to assume the drive is broken. Typically nothing could be further from the truth.
Today’s servo hardware is extensively tested and tends to be highly reliable. It is also highly intelligent. When something goes wrong up or downstream that threatens to damage the drive or the machine the drive may shut down and register a fault. In Horton’s classroom the technicians learn to track down the real reason and fix it.
Students come to appreciate the fact that rather than just learning to troubleshoot the PacDrive automation system they’re also learning to use it as their window into the mechanical and electrical health of their machinery.
“Students bring their experiences with other control systems to class filled with expectations of I/O table and motor parameterization nightmares” Horton concludes. “They leave thinking like analytical troubleshooting technicians.”