I’m a field service engineer for food packaging machines and not an automation specialist, on the other hand can present you with few hints.
For many automation systems to be effective, you have to first have a clear and detailed mechanical plan with all of details finalized. If you do so, you must specify the type of motions involved, e.g.: linear or rotary. This allows you to know the number and types of motors and actuators you’ll need(servo, ac single phase, ac 3 phase, pneumatic actuator).
For each and every motors you may want relay contactors (for single speed discrete/on-off type motors like blower fans and liquid pumps), VFD for speed controllable ac 3-phase motors(a lot more like conveyors, liquid tank level control pumps or rollers).Servo motors need Servo drivers to manipulate their precise movement.
These are your output devices, you will want your input devices to become put down. This could be level sensors, flow sensors, proximity switches and also other devices if required. The reason why i’m stating out this routine is to allow you to define the specifications necessary for your control system hardware requirements. All PLC manufacturers layout their product line-up according to system complexity.
Most PLC hardware is sold as reconfigurable rack chassis. Basically you will find the CPU which is master brain which is supplemented with I/O device that may be slotted in like cards. Additional complex systems which needs servo motor may have servo card in order to connect with servo driver, communication bus cards like CAN-BUS, PROFIBUS and DEVICENET and sensor cards for special sensors like RTD temperature sensors and level sensors.
So workout you IO devices list, then get the necessary software and hardware needed. You will need additional hardware required for for fancy touchscreen technology HMI, line automation and online diagnostic and asset monitoring functions. That’s that the guy with mechanical background can approach complex automation problems.
The solutions varies depending on different manufacturer offering especially if you use beckhoff based systems. A good way to start may be to work on existing machines so that you can learn the basics. Go get a few catalogs from reputable manufacturers to understand industry is offering. I always suggest website visitors to go through Omron catalogues. There is also a free automation online course which will coach you on the baby steps needed.
You have to be capable to design complete PLC systems: architecture design, hardware specfications and selection, logic narratives, logic programming, connection drawings. Everything. Perhaps all you need is extra training for the details of every bit of kit, concerning how to program or properly connect them, yet it’s not brain surgery, an excellent mechanical engineer should probably excel about this because other engineer. The most important element of control system design is to view the process you are going to control and also the goals you need to achieve.