PLC Selection Checklist for Machine Builders
Capture controller requirements before comparing product families and ordering codes.
Map the machine signals
List every input and output with its signal type and required behavior. Separate digital signals from analog measurements and identify any special functions that need manufacturer review. Include planned expansion so spare capacity is an explicit design decision.
Review the connected equipment
Document the devices that must communicate with the PLC and the interfaces they use. An Ethernet port alone does not confirm support for a required industrial protocol. Verify the exact controller and firmware in manufacturer documentation.
Include software and accessories
Check the engineering software version, licensing needs, programming connection and any expansion modules. Confirm the controller supply and output configuration. The same family may contain variants with different electrical interfaces.
Make the quote reproducible
Send the complete controller code with module quantities and accessory requirements. For a replacement, supply the existing project information and exact installed model so a qualified engineer can assess migration work before a purchase decision.
General procurement guidance. Model-specific manufacturer information is linked from each product detail page.