
PLC & Distributed I/O
Controllers and distributed I/O for compact machines, modular systems and plant automation.
- S7-1200
- S7-1500
- ET 200
Siemens automation product catalogue
Browse SIMATIC, SINAMICS, SIRIUS, SITOP and industrial communication families. Honghao reviews article numbers, accessories, compatibility and export requirements before the quotation is finalized.
Common buyer searches
These are the decisions most likely to change the article number, accessory list, replacement scope or panel design.
Start with I/O count, program complexity, motion and safety functions, network interfaces, environmental conditions and future expansion. S7-1200 / G2 is commonly considered for compact machines, while S7-1500 is evaluated for higher performance, larger architectures and advanced functions. The final CPU and modules must be confirmed as one compatible system.
Compare S7-1200 and S7-1500Send the full article number from the device label, including every letter, number and suffix, plus firmware or hardware version when visible. A family name such as G120 or S7-1500 is not enough because it can represent many electrical ratings, interfaces and lifecycle states.
See the verification workflowYes. A useful BOM review checks exact article numbers, quantities, generation compatibility, required accessories, obvious gaps and lifecycle status. Technical assumptions and substitutions should be shown separately before the commercial offer is approved.
View the engineering workflowProduct families
Each family page compares common series, defines selection inputs and links to individual parameter pages.

Controllers and distributed I/O for compact machines, modular systems and plant automation.

Drive platforms for pumps, fans, conveyors, machinery and demanding motion applications.

Visualization platforms for machine operation, diagnostics, alarms and modernization.

Coordinated switching, motor protection and reduced-stress starting components.

Regulated DC power, buffering and selectivity solutions for automation systems.

Network and identification products for connected machines and production systems.
Product selection answers
Use these answers to narrow the product family, understand replacement risk and prepare a quotation that can be checked technically.
Start with function, installed base and the complete article number.
Start with I/O count, program complexity, motion and safety functions, network interfaces, environmental conditions and future expansion. S7-1200 / G2 is commonly considered for compact machines, while S7-1500 is evaluated for higher performance, larger architectures and advanced functions. The final CPU and modules must be confirmed as one compatible system.
Compare S7-1200 and S7-1500Send the full article number from the device label, including every letter, number and suffix, plus firmware or hardware version when visible. A family name such as G120 or S7-1500 is not enough because it can represent many electrical ratings, interfaces and lifecycle states.
See the verification workflowYes. A useful BOM review checks exact article numbers, quantities, generation compatibility, required accessories, obvious gaps and lifecycle status. Technical assumptions and substitutions should be shown separately before the commercial offer is approved.
View the engineering workflowA successor model is an engineering change, not only a purchasing change.
Sometimes the physical and electrical interfaces are close, but CPU behavior, I/O modules, memory, communication, software version and safety functions can still change. A migration review should map hardware, source projects, networks, wiring and acceptance tests before shutdown.
Review the migration scopeProvide the full old and proposed article numbers, mounting cut-out, screen size, PLC protocol, existing project backup, engineering software version and required functions. Hardware availability alone does not prove that the old HMI project will convert without engineering work.
Explore SIMATIC HMI familiesCompare input supply, motor current, overload duty, control method, I/O, fieldbus, braking, EMC accessories, enclosure losses, cable length and parameter backup. The new drive must be validated against the driven load—not selected only by matching kW.
Review SINAMICS selection inputsThe process duty determines whether you need components or an engineered system.
Use a soft starter when the motor normally runs at fixed speed and the main objective is a controlled start or stop. Evaluate a VFD when variable speed, process control, energy optimization or wider torque control is required. Load torque, starts per hour, bypass and harmonic considerations affect the final decision.
Compare starting methodsV20 is typically evaluated for straightforward basic-performance applications. G120 is considered when modular configuration, broader communication, safety functions or a more demanding application architecture is needed. Ratings and options must be checked by exact article number.
Open the drive comparisonDistributed I/O becomes useful when signals are physically spread across a machine or plant and shorter field wiring, modular expansion or remote diagnostics improve the architecture. Network availability, cabinet locations, environment, fail behavior and maintenance access should be reviewed first.
Review the ET 200 selection pageThe quotation should define product identity, documents and project boundary.
It should identify the legal supplier, exact article numbers, quantities, included accessories, technical assumptions, lifecycle or substitution notes, lead-time basis, Incoterm, destination, packing, documents, warranty basis and exclusions. Engineered panels also need an agreed drawing and test scope.
Use the supplier checklistThe project can define an approved BOM, general arrangement, schematics, terminal plan, parameter schedule, FAT record, as-built package, packing list and agreed commercial export documents. Certification or a standard claim is included only when explicitly supported by the contracted scope.
See the document checklistHonghao records the full article number, confirms the quoted configuration against current manufacturer information and separates approved substitutions from the original BOM. Manufacturer authorization, certificates or special traceability are never implied; they must be documented when required.
Read the review and quality basisNot sure which model?