I’m an industry service engineer for food packaging machines instead of an automation specialist, but i can present you with few hints.
For all those automation systems to function, you need to first have a very clear and detailed mechanical plan with all of details finalized. When you do so, you should specify the type of motions involved, e.g.: linear or rotary. This enables you to be aware of number and kinds of motors and actuators you will need(servo, ac single phase, ac 3 phase, pneumatic actuator).
For each and every motors you will need relay contactors (for single speed discrete/on-off type motors like blower fans and liquid pumps), VFD for speed controllable ac 3-phase motors(much more conveyors, liquid tank level control pumps or rollers).Servo motors need Servo drivers to regulate their precise movement.
These are generally your output devices, you’ll need your input devices to become set out. This can be level sensors, flow sensors, proximity switches as well as other devices as needed. The reason i’m stating out this routine is to enable you to define the specifications required for your control system hardware requirements. All PLC manufacturers layout their product line-up depending on system complexity.
Most PLC hardware is sold as reconfigurable rack chassis. Basically there is an CPU which is the master brain that’s supplemented with I/O device which can be slotted in like cards. Additional complex systems which needs servo motor will have servo card for connecting 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 figure out you IO devices list, then receive the necessary software and hardware needed. You may need additional hardware needed for for fancy touchscreen HMI, line automation and internet-based diagnostic and asset monitoring functions. That’s that the guy with mechanical background can approach complex automation problems.
The solutions may differ determined by different manufacturer offering particularly if use beckhoff based systems. The best way to start may be to work with existing machines so that you can discover the basics. Go get yourself a few catalogs from reputable manufacturers to understand the market provides. I always suggest people to go through Omron catalogues. They likewise have a free of charge automation online course that can coach you on the baby steps needed.
You should be able to design complete PLC systems: architecture design, hardware specfications and selection, logic narratives, logic programming, connection drawings. Everything. Perhaps you simply need extra training for the specifics of each bit of equipment, on the way to program or properly connect them, however it is not brain surgery, a great mechanical engineer should probably excel for this every other engineer. The key element of control system design would be to understand the process you are going to control as well as the goals you want to achieve.